HE US005082853A United States Patent (19) 11 Patent Number: 5,082,853 Bodor 45) Date of Patent: "Jan. 21, 1992 54 BRAIN-SPECIFICANALOGUES OF CENTRALLY ACTING AMNES OTHER PUBLICATIONS Dean et al., CA 86:16522h. 76 Inventor: Nicholas S. Bodor, 7211 SW. 97th Chemical Abstracts, vol. 84, Jun. 7, 1976, p. 447, abstract La., Gainesville, Fla. 32608 No. 164580Z. (*) Notice: The portion of the term of this patent Chemical Abstracts, vol. 81, Aug. 5, 1974, p. 24, abstract subsequent to Sep. 13, 2005 has been No. 20899a. disclaimed. Primary Examiner-Jane T. Fan (21) Appl. No.: 505,910 57 ABSTRACT The subject compounds, which are adapted for the (22 Filed: Apr. 4, 1990 site-specific/sustained delivery of centrally acting drug Related U.S. Application Data species to the brain, are compounds of the formula 60) Division of Ser. No. 208,872, Jun. 20, 1988, Pat. No. 4,933,438, which is a division of Ser. No. 785,903, filed (I) as PCT/US85/00236, Feb. 15, 1985, Pat. No. 4,771,059, which is a continuation-in-part of Ser. No. 584,800, D-O Feb. 29, 1984, abandoned. 51 Int. Cl...... A61K 31/44; CO7D 211/90 and the non-toxic pharmaceutically acceptable salts 52) U.S.C...... 514/355; 514/345; thereof, wherein D is the residue of a centrally acting 514/307; 514/309; 514/311; 514/312; 514/348; primary, secondary or tertiary amine and 514/350, 514/354; 514/356; 514/357; 514/358; 54.6/316; 54.6/322; 546/326; 546/296; 546/297; 546/301; 546/302; 546/332; 54.6/329; 54.6/342; 546/298; 546/299; 546/300; 54.6/155; 54.6/156; -NO 54.6/157; 546/158; 546/141; 546/142; 546/145; 546/146; 546/147; 54.6/150, 54.6/152; 546/153 58 Field of Search ...... 54.6/316, 322, 326, 296, is an unsubstituted or substituted dihydropyridyl, dihy 546/297, 301,302,332,329, 342,298,299, 300, droquinolyl or dihydroisoquinolyl radical. The corre 155, 156, 157, 158, 141, 142, 45, 146, 147, 150, sponding ionic pyridinium, quinolinium and 152, 153; 514/355, 307, 345, 309, 311, 312,348, isoquinolinium salts 350, 354, 356, 357, 358 (56) References Cited U.S. PATENT DOCUMENTS D-N) x-, 4,479,932 10/1984 Bodor...... 424/9 wherein X is the anion of a non-toxic pharmaceuti FOREIGN PATENT DOCUMENTS cally acceptable acid, are also disclosed. 83/03968 11/1983 PCT Int'l Appl. . 822351 10/1959 United Kingdom. 26 Claims, No Drawings 5,082,853 1 2 The widely accepted concept describes the boundary as BRAN-SPECIFICANALOGUES OF CENTRALLY a fat-like layer interspersed with small pores, although ACTING AMNES the BBB is not a simple, anatomically well-defined uni tary physical entity. Shuttleworth, Prog. Exp. Tumor CROSS-REFERENCE TO RELATED Res., 17, 279 (1972). Penetration of such a barrier may APPLICATION occur by several processes; lipid soluble substances may This application is a division of application Ser. No. passively penetrate into the cells, while small molecules 07/208,872, filed Jun. 20, 1988, now U.S. Pat. No. such as water and urea may pass through the pores. In 4,933,438, issued Jun. 12, 1990, which is a division of addition to these simple physical processes, carrier application Ser. No. 06/785,903, filed as PCT/US85/ 10 mediated and active transport processes govern the 00236, Feb. 15, 1985, now U.S. Pat. No. 4,771,059, movement of many molecules through the BBB. Thus, which is a continuation-in-part of applicant's copending it is generally accepted that lipid solubility, degree of application Ser. No. 584,800, filed Feb. 29, 1984, now ionic dissociation or protonation and the ability of tem abandoned. porary combination with membrane constituents affect FIELD OF THE INVENTION 15 delivery through the BBB. It has been shown, for exam The present invention relates to new derivatives of ple, that in the class of barbiturates, a quantitative corre centrally acting amines in which a primary, secondary lation could be established between their ease to pass or tertiary amine function has been replaced with a into the brain (as reflected by the different times of dihydropyridine/pyridinium salt redox system. The onset of anesthetic action) and their lipid/water parti new dihydropyridine analogues are a delivery system tion coefficient. Mark et al., J. Pharmacol and Exp. for the corresponding new quaternary compounds, Therap, 123, 79 (1957). The role of lipid solubility in which are pharmacologically active in vivo and are drug penetration through the BBB is also exemplified characterized by site-specific and sustained delivery to by the better absorption of the sparingly water-soluble the brain. 25 thiamine propyl disulfide (TPD) as compared to the BACKGROUND OF THE INVENTION water-soluble thiamine hydrochloride (THCl). The delivery of drug species to the brain is oftimes Thomson et al, Ann. Int, Med, 74, 529 (1971). Some seriously limited by transport and metabolism factors materials such as glucose and amino acids are trans and, more specifically, by the functional barrier of the ported by active mechanism, characterized by satura endothelial brain capillary wall, i.e. the blood-brain 30 tion, bidirectional molecular specificity, bi-directional barrier or BBB. Site-specific delivery and sustained competitive inhibition and bidirectional countertran delivery of drugs to the brain are even more difficult. sport Fishman, Am. J. Physiol, 206, 836 (1964). Indeed, the barriers separating plasma from the brain Changes in permeability of the BBB can be caused by and cerebrospinal fluid (CSF) are complex systems several pathological and toxicological processes. Par involving passive and active transport and subserve a 35 dridge, Connor and Crawford, CRC Crit, Rev. Toxicol, number of important functions. The boundary between 179 (1975). A general increase in the barrier permeabil plasma and the central nervous system (CNS) is much ity, such as a nonspecific breakdown of the barrier has, less permeable than that between plasma and other however, several consequences, including cerebral tissue cells to a variety of water soluble substances, such edema. as organic electrolytes, organic acids and bases, as well It too is well documented that the BBB is relatively as to large molecules such as proteins. Such a barrier impermeable to the ionized forms of drugs and other also provides a path for clearance from the brain of the molecules. Drugs which are weak organic electrolytes breakdown products of cellular metabolism. The CNS appear to pass from blood to CSF to reach a steady state and its fluids can be considered basically a three-com ratio characteristic of each molecule according to its partment system: the blood or the plasma, CSF and pka and the existence of a normal pH gradient between brain tissue. There is a diffusion-controlled exchange blood and CSF. It is clear that it is the most difficult for between CSF and the extracellular fluid (CF) of the quaternary pyridinium or ammonium salts to penetrate brain. It has also been suggested that the permeabilities the BBB. of blood-CSF and blood-brain barriers are practically And removal of substances from the brain and CSF is identical with respect to drugs and other foreign sub obviously a significant factor in regulating drug concen stances. Mayer et al, J. Pharmacol, and Exp. Therap, trations in the CNS. There are several efflux processes: 125, 185 (1959). bulk flow via the arachnoid villi, diffusion of lipid solu The BBB is, moreover, basically the result of the fact ble substances into brain and blood, active transport and that the endothelial cells in the brain capillaries are metabolism by adjacent meninges. Once a drug or me joined by continuous, tight intercellular junctions, such tabolite enters the CSF from blood or brain by simple that material has to pass through the cells rather than diffusion, it may rapidly be removed, either by nonse between them in order to move from blood to brain. It lective bulk flow or by active transport mechanism is interesting that there are areas within the brain, such associated with the choroid plexus or other nondefined as the subfornical body and the postremia, in which the structures in the CSF compartment. It is generally ac capillary cells are not closely linked so that they lack cepted that highly lipid-soluble drugs leave the CSF the characteristics of the BBB. They provide the entry more rapidly than poorly lipid-soluble ones, but the of small amounts of compounds which would not ordi barrier to passage of compounds from CSF has only narily enter the barriers. Hoffman and Olszewzki, Neu superficial similarity to the blood-CSF barrier. rology (Minneap.), 11,1081 (1961). m Drug elimination processes from the brain are signifi Foreign compounds which enter organs other than 65 cantly directly related to drug accumulation in the the central nervous system with ease, may penetrate the brain. It is generally assumed that efflux in the opposite CNS slowly or hardly at all. A number of theories con direction involves almost the same processes as for cerning the nature of the barrier have been proposed. entry, except that the role of the bulk flow and the 5,082,853 3 4. metabolic processes in the brain are not to be over dihydropyridine latentiated prodrug form thereof. looked. Thus, a hydrophilic compound (2-PAM) was made The two elimination processes studied in the earlier lipoidal (i.e. lipophilic) by making its dihydropyridine literature and which can be said to have a certain bear form (Pro-2-PAM) to enable its penetration through ing on the present invention involve elimination from 5 lipoidal barriers. This simple prodrug approach allowed the brain of ionic species. Thus, it is found that non the compound to get into the brain as well as other metabolized ionic species, such as the acetate ion, have organs, but this manipulation did not and could not a three times slower elimination rate from the CSF than result in any brain specificity. On the contrary, such from the blood. Freundt, Arz, Forsch, 23, 949 (1973). approach was delimited to relatively small molecule An even more dramatic change in the elimination rate 10 quaternary pyridinium ring-containing drug species and was found in the case of a quaternary piperidinium salt. did not provide the overall ideal result of brain-specific, The quaternary salt, formed in situ after delivery of a sustained release of the desired drug, with concomitant haloalkylamine, which undergoes cyclization to the rapid elimination from the general circulation, en quaternary salt, in the brain, as well, was found to have hanced drug efficacy and decreased toxicity. No "trap an at least ten times slower elimination rate from the 15 ping' in the brain of the 2-PAM formed in situ resulted, brain than from the rest of the body. It was concluded and obviously no brain-specific, sustained delivery oc by the authors Ross and Froden, Eur, J. Pharmacol, 13, curred as any consequence thereof: the 2-PAM was 46 (1970) that the outflow rate of the quaternary salt eliminated as fast from the brain as it was from the corresponded to the inflow rate. Similar results were general circulation and other organs. obtained for the erythrocytes: the efflux of the quater- 20 Compare U.S. Pat. Nos. 3,929,813 and 3,962,447; nary salt was very slow. Ross, J. Pharm. Pharmacol, 27, Bodor et al, J. Pharm. Sci, 67, No. 5, 685 (1978). See 322 (1975). also Bodor, "Novel Approaches for the Design of A dihydropyridine-pyridinium redox system has Membrane Transport Properties of Drugs", in Design of now been successfully applied to delivery to the brain Biopharmaceutical Properties Through Prodrugs and Ana of a number of drugs. Generally speaking, according to 25 logs, Roche, E. B. (ed.), APhAAcademy of Pharmaceu this system, a dihydropyridine derivative of a biologi tical Sciences, Washington, D.C., 98-135 (1976). Subse cally active compound is synthesized, which derivative quent extension of this first approach to delivering a can enter the CNS through the blood-brain barrier much larger quaternary salt, berberine, to the brain via following its systemic administration. Subsequent oxi its dihydropyridine prodrug form was, however, found dation of the dihydropyridine species to the corre- 30 to provide site-specific sustained delivery to the brain of sponding pyridinium salt leads to delivery of the drug to that anticancer agent. See Bodor et al, Science, Vol.214, the brain. Dec. 18, 1981, pp. 1370-1372. Two main approaches have been used thus far for The second approach for delivering drugs to the delivering drugs to the brain using this redox system. brain using the redox system involves the use of a pyri The first approach involves derivation of selected drugs 35 dinium carrier chemically linked to a biologically active which contain a pyridinium nucleus as an integral struc compound. Bodor et al, Science, Vol. 214, Dec. 18, tural component. This approach was first applied to 1981, pp. 1370-1372, outlines a scheme for this specific delivering to the brain N-methylpyridinium-2-carbal and sustained delivery of drug species to the brain, as doxime chloride (2-PAM), the active nucleus of which depicted in the following Scheme i: constitutes a quaternary pyridinium salt, by way of the

SCHEME 1: BBB, BLOOD-BRAIN BARRIER. (D) + (QC)* Es (D-QCI* Estone (D-DHC)

K DELVERY TO BODY /ELMINATION D-DHC) D-DHC) INTHE BRAN NCRCULATORY SYSTEM AND ORGANS * oxidAroN OXEDATIONNYTYO

D-QC) ENZYMATIC ENZYMATIC D-QCit IN THE BRAIN CLEAVAGE CLEAVAGE IN CIRULATORY SYSTEM

K4. K4. K2 5 5,082,853 6 -continued SCHEME 1: BBB, BLOOD-BRAIN BARRIER. (D - (QC) (D+ (QC)

: K3

BBB

EMINATION According to the scheme in Science, a drug D is cou pled to a quaternary carrier QC and the D-QC 15 Testing of the N-methyl derivative in vivo supported which results is then reduced chemically to the lipoidal the criteria set forth in Scheme 1. Bodor etal speculated dihydro form D-DHC. After administration of D that various types of drugs might possibly be delivered DHC in vivo, it is rapidly distributed throughout the using the depicted or analogous carrier systems and body, including the brain. The dihydro form D-DHC indicated that use of N-methylnicotinic acid esters and is then in situ oxidized (rate constant, k) (by the amides and their pyridine ring-substituted derivatives NAD2NADH system) to the ideally inactive original was being studied for delivery of amino- or hydroxyl D-QC+ quaternary salt which, because of its ionic, containing drugs, including small peptides, to the brain. hydrophilic character, should be rapidly eliminated No other possible specific carriers were disclosed. from the general circulation of the body, while the Other reports of this work with the redox carrier system blood-brain barrier should prevent its elimination from 25 have appeared in The Friday Evening Post, Aug. 14, the brain (k3>>k2; k3>>k). Enzymatic cleavage of 1981, Health Center Communications, University of the D-QC that is "locked' in the brain effects a sus Florida, Gainesville, Fla.; Chemical & Engineering tained delivery of the drug species D), followed by its News, Dec. 21, 1981, pp. 24-25; and Science News, Jan. normal elimination (ks), metabolism. A properly Se 2, 1982, Vol. 121, No. 1, page 7. More recently, the lected carrier QC will also be rapidly eliminated 30 redox carrier system has been substantially extended in from the brain (kg) >k2). Because of the facile elimina terms of possible carriers and drugs to be delivered. See tion of D-QC+ from the general circulation, only International Patent Application No. minor amounts of drug are released in the body PCT/US83/00725, filed May 12, 1983 and published (k3>>k); D will be released primarily in the brain Nov. 24, 1983 under International Publication No. (kk2). The overall result ideally will be a brain 35 W083/03968. Also see Bodor et al., Pharmacology and specific sustained release of the target drug species. Therapeutics, Vol. 19, No. 3, pp. 37-386 (1983). Specifically, Bodor et al worked with phenylethyla Nevertheless, serious need also exists in this art for mine as the drug model. That compound was coupled to new, centrally acting drugs which can be site-specifi nicotinic acid, then quaternized to give compounds of 40 cally and sustainedly delivered to the brain, while at the the formula same time avoiding the aforesaid noted and notable disadvantages and drawbacks associated with penetra tion of the blood-brain barrier, with dihydropyridine latentiated prodrug forms of drug species themselves comprising a pyridinium salt active nucleus, with the 45 necessity for introducing critically coordinated and (Oroi (O designed, release rate-controlling substituents onto any R particular drug carrier moiety, and/or with the limita tion of delivery of only known drug entities. SUMMARY AND OBJECTS OF THE (R = CH3 or O) ), INVENTION Accordingly, a major object of the present invention is the provision of a new approach for delivering drugs which were subsequently reduced by sodium dithionite to the brain using the redox system. This approach to the corresponding compounds of the formula 55 provides new derivatives of centrally acting amines in which a primary, secondary or tertiary amine function has been replaced with a dihydropyridine/pyridinium salt redox system. The new dihydropyridine analogues of the invention are characterized by the structural formula OrN ro R (I) D-NO (R = CH3 or O) ), 65 Wherein D is the residue of a centrally acting primary, secondary or tertiary amine, and 5,082,853 8 The nontoxic pharmaceutically acceptable salts of the compounds of formula (I) are also within the ambit of this invention. -N) The new dihydropyridine analogues of formula (I) act as a delivery system for the corresponding quater nary compounds in vivo; the quaternary derivatives, is a radical of the formula which also are chemical intermediates to the dihydro compounds, are pharmacologically active and are char acterized by site-specific and sustained delivery to the 10 brain when administered via the corresponding dihy dropyridine form. The new quaternary salts are charac terized by the structural formula

(II) 15 D-N.) x -N2 -N2 N wherein D is defined as with formula (), X is the (R) N: O & anion of a non-toxic pharmaceutically acceptable acid and (R)n (c) (d) wherein the dotted line in formula (a) indicates the -N) presence of a double bond in either the 4 or 5 position of the dihydropyridine ring; the dotted line in formula (b) indicates the presence of a double bond in either the 2 or is a radical of the formula 3 position of the dihydroquinoline ring system; m is zero or one; n is zero, one or two; p is zero, one or two, provided that when p is one or two, each R in formula 30 (b) can be located on either of the two fused rings; q is zero, one, or two, provided that when q is one or two, each Rinformula (c) can be located on either of the two fused rings; and each R is independently selected from (g) gO) the group consisting of halo, C1-C7 alkyl, C1-C7 alkoxy, 35. (R) (R) C2-C8 alkoxycarbonyl, C2-C8 alkanoyloxy, C1-C7 halo (a) (b) alkyl, C1-C, alkylthio, C1-C, alkylsulfinyl, C1-C, alkyl sufonyl, -CH=NOR" wherein R" is H or C1-C7 N alkyl, and -CONR'R' wherein R' and R", which can be the same or different, are each H or C11oc C7 alkyl. or RO Preferably, n, m, p or q is one and R is located in the 3 position of the dihydropyridine ring, in the 3 position of (R) the dihydroquinoine ring system or in the 4 position of (c) the dihydroisoquinoline ring system. Most preferably, R is -CONH2. 45 wherein n, p, q and R are defined as with formula (I). Briefly then, the present invention features a dihy dropyridine-pyridinium salt redox system for the spe cific and sustained delivery of a centrally acting drug to the brain according to the following Scheme 2:

SCHEME 2

D-) (I) Dunstation K BLOOD & OTHER TISSUES SSK DISTRIBUTION SS BRAIN K6 Jonation K3 Judition 5,082,853 9 10 -continued SCHEME 2

BBB D-SE) X- (II) y \

EXCRETION METABOLISM EXCRETION METABOLISM Ks > K7 Ks >> K5 Scheme 2 shows the expected sequence of events following administration of a compound of formula (I). Due to its lipophilic nature, the dihydropyridine com 15 2 carbon atoms and bears 1 to 3 halogen substituents, pound of formula (I) will distribute throughout the e.g. chloromethyl or trifluoromethyl. body and has easy access to the brain through the The term "C-C alkylthio' includes straight and blood-brain barrier. Upon oxidation, which occurs branched chain radicals of the type throughout the body, the formula (I) compound will be converted to the corresponding quaternary of formula 20 (C-C alkyl)-S- (II). The quaternary form will be "locked" preferen tially in the brain, since it can be excreted easily periph wherein C1-C alkyl is defined as before. When R is erally, but cannot move readily through the BBB. Sus alkylthio, it is preferably methylthio. tained levels of the formula (II) quaternary will be pres The terms "C-C alkylsulfinyl' and "C-C7 alkylsul ent at the site of action, the brain, resulting in longer 25 fonyl' designate radicals of the formulas duration of action. (C-C alkyl) -SO DETALED DESCRIPTION OF THE INVENTION and 30 More particularly in accord with the present inven (C1-C alkyl) -SO2-, tion, the following definitions are applicable: The term "lipoidal' as used herein is intended to respectively, wherein C1-C7 alkyl is defined as before. mean lipid-soluble or lipophilic. When R is alkylsulfinyl or alkylsulfonyl, methylsulfinyl The term "halo' encompasses fluoro, chloro, bromo and methylsulfonyl are preferred. and iodo. 35 When R is -CH=NOR", it is preferably -CH The term "C1-C, alkyl” includes straight and NOH branched lower alkyl radicals having up to seven car When Ris-CONR'R'', is is preferably -CONH2 or bonatoms. When R, R', R", and/or R" are C1-C alkyl, -CONCH3)2. they are preferably methyl or ethyl. The expression "hydroxyl protective group' as used The term "C1-C7 alkoxy” includes straight and hereinbelow is intended to designate a group which is branched chain lower alkoxy radicals having up to inserted in place of the hydrogen atom(s) of an OH seven carbon atoms. When R is C1-C alkoxy, it is pref group or groups in order to prevent premature metabo erably methoxy or ethoxy. lism of said OH group or groups prior to the com The term "C2-C8 alkoxycarbonyl' designates pound's reaching the desired site in the body. Typical straight and branched chain radicals of the formula 45 hydroxyl protective groups contemplated by the pres ent invention are acyl groups and carbonates O When the hydroxyl protective group is acyl (i.e., . when it is an organic radical derived from a carboxylic (C-C alkyl)-O-C- acid by removal of the hydroxyl group), it preferably wherein the C1-C7 alkyl group is defined as above. represents an acyl radical selected from the group con When Risalkoxycarbonyl, it is preferably ethoxycarbo sisting of alkanoyl having 2 to 8 carbon atoms; alkenoyl nyl or isopropoxycarbonyl. having one or two double bonds and 3 to 8 carbon The term "C2-Cs alkanoyloxy' designates straight atoms; and branched chain radicals of the formula 55 cycloalkyl-CH2-C- (C-C alkyl)-C-O- wherein the cycloalkyl portion contains 3 to 7 ring wherein the C-C7 alkyl group is defined as above. atoms and r is zero, one, two or three; phenoxyacetyl; When R is alkanoyloxy it is preferably acetoxy, pyridinecarbonyl; and pivalyloxy or isobutryloxy. The term "C1-C7 haloalkyl' designates straight and branched chain lower alkyl radicals having up to seven 65 phenyl-CH2-C- carbon atoms and bearing one or more halo substituents (F, Cl, Br or I), which can be the same or different. wherein r is zero, one, two or three and phenyl is unsub Preferably, when Rishaloalkyl, the group contains 1 or stituted or is substituted by 1 to 3 alkyl each having 1 to 5,082,853 11 12 4 carbon atoms, alkoxy having 1 to 4 carbon atoms, halo, trifluoromethyl, dialkylamino having 2 to 8 car O bon atoms or alkanoylamino having 2 to 6 carbon atOS. Y'al-Oa-Ca When the acyl group is alkanoyl, there are included both unbranched and branched alkanoyl, for example, i.e., it is an organic radical which can be considered to acetyl, propionyl, butyryl, isobutyryl, valleryl, isovale be derived from a carbonic acid by removal of the hy ryl, 2-methylbutanoyl, pivalyl (pivaloyl), 3-methylpen droxyl group from the COOH portion. Y' preferably tanoyl, 3,3-dimethylbutanoyl, 2,2-dimethylpentanoyl represents alkyl having 1 to 7 carbon atoms; alkenyl and the like. Pivalyl, isobutyryl and isovaleryl are espe O having one or two double bonds and 2 to 7 carbon cially preferred. atons; When the acyl group is alikenoyl, there are included, for example, crotonyl, 2,5-hexadienoyl and 3,6-octadi cycloalkyl-CH2 enoyl. When the acyl group is 15 wherein the cycloalkyl portion contains 3 to 7 ring atoms and r is zero, one, two or three; phenoxy; 2-, 3-, or 4-pyridyll; or cycloalkyl-CH-C-, phenyl-CH2 20 there are included cycloalkanecarbonyl and cycloalk wherein ris zero, one, two or three and phenyl is unsub anealkanoyl groups wherein the cycloalkane portion stituted or is substituted by 1 to 3 alkyl each having 1 to can optionally bear i or 2 alkyl groups as substituents, 4 carbon atoms, alkoxy having 1 to 4 carbon atoms, e.g. cyclopropanecarbonyl, 1-methylcyclopropanecar halo, trifluoromethyl, dialkylamino having 2 to 8 car bonyl, cyclopropaneacetyl, a-methylcyclopropanea 25 bon atoms or alkanoylamino having 2 to 6 carbon cetyl, 1-methylcylopropaneacetyl, cyclopropanepro atoms. Most preferably, Y" is C1-C7 alkyl, particularly pionyl, a-methylcyclopropanepropionyl, 2-isobutylcy ethyl or isopropyl. clopropanepropionyl, cyclobutanecarbonyl, 3,3-dime Similarly, the expression "carboxyl protective thylcyclobutanecarbonyl, cyclobutaneacetyl, 2,2- group' as used hereinbelow is intended to designate a dimethyl-3-ethylcyclobutaneacetyl, cyclopentanecar 30 group which is inserted in place of the hydrogen bonyl, cyclohexaneacetyl, cyclohexanecarbonyl, cy atoms(s) of a COOH group or groups in order to pre cloheptanecarbonyl and cycloheptanepropionyl. Cy vent premature metabolism of said COOH group is clohexanecarbonyl is especially preferred. groups prior to the compound's reaching the desire site When the acyl group is pyridinecarbonyl, there are in the body. Typical carboxyl protective groups are the included picolinoyl (2-pyridinecarbonyl), nicotinoyl 35 groups encompassed by Y above, especially C1-C, (3-pyridinecarbonyl) and isonicotinoyl (4-pyridinecar alkyl, particularly ethyl, isopropyl and t-butyl. While bonyl). such simple alkyl esters and the like are often useful, When the acyl group is other carboxyl protecting groups may be selected in order to achieve greater control over the rate of in vivo hydrolysis of the ester back to the acid and thus enhance phenyl-CH-C-, drug delivery. To that end, carboxyl protecting groups such as the following may be used to replace the hydro there are included, for example, benzoyl, phenylacetyl, gen of the -COOH group: a-phenylpropionyl, S-phenylpropionyl, p-toluyl, m-tol 45 uyl, o-toluy, o-ethylbenzoyl, p-tert-butylbenzoyl, 3,4- dimethylbenzoyl, 2-methyl-4-ethylbenzoyl, 2,4,6- seCH-C C-CH3, trimethylbenzoyl, m-methylphenylacetyl, p-isobutyl O- O phenylacetyl, As-(p-ethylphenyl)propionyl, p-anisoyl, C m-anisoyl, o-anisoyl, m-isopropoxybenzoyl, p-methoxy O phenylacetyl, m-isobutoxyphenylacetyl, n-die thylaminobenzoyl, 3-methoxy-4-ethoxybenzoyl, 3,4,5- O trimethoxybenzoyl, p-dibutylaminobenzoyl, 3,4-die alkoily, thoxyphenylacetyl, f-(3,4,5-trimethoxyphenyl)propio nyl, o-iodobenzoyl, m-bromobenzoyl, p-chlorobenzoyl, 55 O p-fluorobenzoyl, 2-bromo-4-chlorobenzoyl, 2,4,6-tri alkoolly o chlorobenzoyl, p-chlorophenylacetyl, a-(m-bromo phenyl)propionyl, p-trifluoromethylbenzoyi, 2,4-di(tri -alk-O-alkyi, fluoromethyl)-benzoyl, m-trifluoromethylphenylacetyl, A-(3-methyl-4-chlorophenyl)propionyl, p-dime wherein alk is C1-C5 straight or branched alkylene and thylaminobenzoyl, p-(N-methyl-N-ethylamino)benzoyl, the alkyl radical is straight or branched and contains 1 O-acetamidobenzoyl, m-propionamidobenzoyl, 3 to 7 carbon atoms chloro-4-acetamidophenylacetyl, p-n-butoxybenzoyl, 2,4,6-triethoxybenzoyl, B-(p-trifluoromethylpehnyl)- O O CH3 propionyl, 2-methyl-4-methoxybenzoyl, p-acetamido 65 / phenylpropionyl, and 3-chloro-4-ethoxybenzoyl. (e.g. -Hocochsch, -CH:oc-crch, and -CH2OCH3). When the hydroxyl protective group is a carbonate CH3 CH3 grouping, it has the structural formula 5,082,853 13 14 By "centrally acting primary, secondary or tertiary amine/decongestant; noracymethadol, a narcotic anal amine" as used herein there is intended any drug species gesic of the methadone-type; piminodine, a narcotic or the like which contains a primary amino, secondary analgesic of the meperidine-type; tracazolate, a sedati amino or tertiary amino function, a significant (usually, ve/hypnotic; tiletamine, an anticonvulsant; proprano principal) pharmacological activity of which is CNS lol, metoprolol, nadolol, timolol and atenolol, which are and a result of direct action in the brain. The term A-blockers; prizidilol, a centrally acting hypotensive; "drug' as used herein means any substance intended for benzoctamine, a sedative/muscle relaxant which struc use in the diagnosis, cure, mitigation, treatment or pre turally is an analogue of the phenothiazine tranquilizers; vention of disease or in the enhancement of desirable chlordiazepoxide, a tranquilizer of the benzodiazepine physical or mental development and conditions in man 10 type; methamphetamine, fencamfamin, fenozolone and or animal. zylofuramine, which are sympathomimetic amines/- Exemplary such centrally acting primary amines are cerebral stimulants; desipramine, nortriptyline, octrip sympathetic stimulants and related nervous system tyline, protriptyline and maorotiline. which are cerebral agents, e.g., phenylethylamine (a stimulant), dopamine stimulants/tricyclic antidepressants of the dibenzaze (a neurotransmitter and dopaminergic agent used, e.g., 15 pine-type; amedalin, bupropion, cartazolate, daledalin, in the treatment of Parkinsonism or hyperprolac difluanine, fluoxetine and nisoxetine, which also are tinemia), tyramine (a stimulant), L-DOPA (a dopamine cerebral stimulants; bethanidine, a hypotensive; and precursor used, for example, in the treatment of Parkin ephedrine and pseudoephedrine, which are sympatho sonism); narcotic analgesics; other stimulants: small ninetic amines. peptides, such as the di-, tri-, tetra- and pentapeptides, 20 Exemplary such centrally acting tertiary amines and and other small 2-20 amino acid unit containing pep the classes of drugs of which they are representative are tides, e.g., the enkephalins (for example, Tyr-Gly-Gly as follows: methadone, levomethadyl acetate, dex Phe-Leu), which, besides being analgesics, initiate epi tromoramide, propoxyphene, carbiphene and pyrroli leptic activity in the brain at doses that are about tenfold phine, which are narcotic analgesics of the methadone lower than for effecting analgesic activity; larger pep 25 type: phenampromide and tilidine, which are narcotic tides, such as pituitary hormones and related agents; analgesics of the meperidine-type; methotrimeprazine, growth-promoting substances; amphetamine-like drugs; which is a phenothiazine analgesic; clozapine and perla anticancer and anti-Parkinsonism agents; antihyperten pine, which are sedatives/hypnotics/anticonvulsants of sives; agents to enhance learning capacity and the mem the benzodiazepine-type; cloperidone, a sedative/hyp ory processes, including treatment of dementias, such as 30 notic of the quinazolone-type: atolide, an anticonvul Alzheimer's disease; antibacterials; monoamine oxidase sant; guanethidine, a sympatholytic hypotensive; chlor (MAO) inhibitor drugs; CNS or brain important/essen promazine, propiomazine, periphenazine, trifluopera tial amino acids, such as tryptophan (which is an antide zine, promazine, triflupromazine, acepromazine, aceto pressant as well as a nutrient); and any like centrally phenazine, butaperazine, carphenazine, fluphenazine, acting primary amines. 35 prochlorperazine, thiopropazate, piperacetazine and Other illustrative ultimate species of centrally active pipotiazine palmitate, which are tranquilizers/antip drug entities containing a primary amino group and the sychotics of the phenothiazine-type, a number of which classes of drugs of which they are representative are as are also useful as sedatives (e.g. chlorpromazine, propi follows: amphetamine, dextroamphetamine, levan omazine, perphenazine and trifluoperazine); chlorpro phetamine, aletamine, cypenamine and phentermine, thixine, a thioxanthine calming agent which structurally which are sympathomimetic amines/cerebral stimulants is an analogue of the phenothiazine tranquilizers; thio and appetite suppressants; etryptamine, a cerebral stim thixine, a thioxanthine alerting agent (used, e.g., in ulant; anilleridine, which is a narcotic analgesic; methyl chronic withdrawn schizophrenia) which structurally is dopa, which is a sympatholytic agent used, e.g., in hy an analogue of the phenothiazine tranquilizers; doxepin pertension; tranylcypromine, a sympathomimetic cere 45 and cidoxepin, tricyclic anti-depressants which struc bral stimulant/MAO inhibitor and anti-depressant; nor turally are dibenzoxapine analogues of the phenothi epinephrine, a sympathetic stimulant/adrenergic agent: azine tranquilizers; loxapine, a tranquilizer/antip hydralazine, a hypotensive: amnxicillin and ampicillin, sychotic (used, e.g., in treating chronic and acute schiz which are penicillin-type, antibiotics; guanethidine, a ophrenia) which structurally is an analogue of the phe hypotensive/sympatholytic; GABA, Y-vinyl GABA SO nothiazine tranquilizers clomacran, clopenthixol and and Y-acetylenic GABA, neurotransmitters for possible clothiapine, which are antipsychotics which structur use in epilepsy; doxorubicin and daunamycin, antican ally are analogues of the phenothiazine tranquilizers; cer/antitumor agents; cephalexin, a cephalosporin anti clozapine, dineprozan, perlapine and pinoxepin, which biotic; ACTH (corticotropin); LH-RH, a neurotrans also are analogues of the phenothiazine tranquilizers mitter; melphalan, a nitrogen mustard-type anticancer 55 and are variously used as sedatives, hypnotics and tran Mantitumor agent; DON, an anticancer urea derivative: quilizers; pipamperone, an antipsychotic; flurazepam, nimustine, an anticancer/antitumor nitrosourea deriva adinazolam, flumezapine and metiapine, sedatives of the tive: amiphenazole, a stimulant; debrisoquin, a hypoten benzodiazepine-type, some of which are also used as sive: bacampicillin and pivampicillin, which are penicil hypnotics; doxapram, a medullary stimulant; dimetha lin-type antibiotics; ceforanide and cefroxadine, which zan, a xanthine-type cerebral stimulant; prolintane and are cephalosporin-type antibiotics; and 6(hydrox thozalinone, sympathomimetic amine-type cerebral yimino)phenyl)methyl-1-(methylethyl)sulfonyl)-1H stimulants; gamfexine, a cerebral stimulant of the diphe benzimidazol-2-amine, an antiviral agent. nylmethane analogue type; cyclobenzaprine, a muscle Exemplary centrally acting secondary amines in ac relaxant; clodazon, an antidepressant; amitriptyline, cord with this invention and the classes of drugs of 65 imipramine, opipramol, doxepin, cidoxepin, amoxapine, which they are representative are as follows: mitoxan azipramine, butriptyline, clomipramine, dibenzepin, trone, an anticancer/antitumor agent: epinephrine, an dothiepin, intriptyline, ketipramine, melitracen and adrenergic agent; phenylephrine, a sympathomimetic trimipramine, which are tricyclic antidepressants/cere 5,082,853 15 16 bral stimulants of the dibenzazepine-type (i.e. diben droxylated metabolites of phenothiazine tranquilizers, zazepines and their analogues such as dibenzoxepines), e.g. 7-hydroxychlorpromazine. Other CNS active me all of which can be considered as analogues of the phe tabolites for use herein will be apparent to those skilled nothiazine tranquilizers; and cyclindole, difluamine, in the art. Typically, these CNS active metabolites have fantridone, flubanilate, iprindole, modaline, piranda been identified as such in the scientific literature but mine, pyrovalerone, tandamine, thiazesim, trazodone have not been administered as drugs themselves. In and trebenzomine, which also are cerebral stimulants. many cases, the active metabolites are believed to be Preferred classes of centrally acting primary, second comparable in CNS activity to their parent drugs; fre ary and tertiary amines encompassed hereby are the quently, however, the metabolites have not been admin central neurotransmitters, anticancer and antitumor 10 istered per se because they are not themselves able to agents, antiviral agents, memory enhancers, hypoten penetrate the blood-brain barrier. sives, sedatives, tranquilizers, anti-psychotics, narcotic As indicated hereinabove, diagnostic agents, includ analgesics and cerebral stimulants, especially preferred ing radiopharmaceuticals, are encompassed by the ex cerebral stimulants being the tricyclic antidepressants. pression "centrally acting drug' or the like as used Among the neurotransmitters, there can be mentioned 15 herein. Any diagnostic agent which can be derivatized amino acids, such as GABA, GABA derivatives and to afford a compound of formula (I) which will pene other omega-amino acids, as well as glycine, glutamic trate the BBB and concentrate in the brain in its quater acid, tyrosine, aspartic acid and other natural amino nary form (II) and can be detected therein is encom acids; catecholamines, such as dopamine and norepi passed by this invention The diagnostic may be "cold" nephrine; serotonin, histamine and tryptamine; and pep 20 and be detected by X-ray (e.g. radiopaque agents) or tides such as neurotensin, luteinizing hormone-releasing other means such as mass spectrophotometry, NMR or hormone (LHRH), somatostatin, enkephalins such as other non-invasive techniques (e.g. when the compound met-enkephalin and leu-enkephalin, endorphins such includes stable isotopes such as C 13, N 15, O 18, S 33 as y-, a- and R-endorphins, and vasopressin. Synthetic and S 34). The diagnostic alternatively may be "hot", and semi-synthetic analogues, e.g. analogues of LHRH 25 i.e. radiolabeled, such as with radioactive iodine (I 123, in which one or more amino acid(s) has/have been I 125, I 131) and detected/imaged by radiation detec eliminated and/or replaced with one or more different tion/imaging means. Typical radiolabeled diagnostics amino acid(s), and which may be agonists or antago include diotyrosine (I 125, I 131), p-iodo-N-iso nists, are also contemplated, e.g. the primary and sec propylamphetamine (I 123), iotyrosine (I 131) and ondary amine LHRH analogues disclosed in U.S. Pat. 30 iodonetaraminol (I 123), which has the structural for Nos. 4,377,574, 3,917,825, 4,034,082 and 4,338,305. mula Among the anticancer and antitumor agents, there can be mentioned L-alanosine, DON, bactobolin, acivicin, melphalan, adriamycin (doxorubicin), daunomycin, CH3 mitoxantrone and nimustine. Among the antiviral 35 HO CHCHNH2. agents, there can be mentioned amantadine (also of possible value as an anti-Parkinsonism agent); OH diarylamidines such as 5-amidino-2-(5-amidino-2-ben Is zofuranyl)indole and 4,6-diimidazolino:2-phenylben zo(b)thiophen: 2-aminooxazoles such as 2-guanidino Yet other radiolabeled diagnostics include p-iodophene 4,5-di-n-propyloxazole and 2-guanidino-4,5-diphenylox thylamine and p-iodobenzylamine (labeled, e.g. with I azole: benzinidazole analogues such as the syn and anti 123 or I 125). In the case of diagnostics, as in the case of isomers of 6(hydroxyimino)phenyl)methyl)-1-(1- drugs which are for the treatment of disease, the methylethyl)sulfonyl)-1H-benzimidazol-2-amine; and "locked in' quaternary from will be the form that is glycosides such as glucosamine and 6-amino-6-deoxy 45 imaged or otherwise detected, not the original diagnos D-glucose. Among the hypotensives, there can be men tic itself. Moreover, any of the centrally acting drugs tioned methyldopa, debrisoquin, hydralazine, and gua encompassed by this invention which are intended for nethidine and its analogues. Among the sedatives, tran the treatment or prevention of medical disorders but quilizers and antipsychotics, there can be mentioned the which can be radiolabeled, e.g. with a radioisotope such many specific compounds of this type already disclosed as iodine, or labeled with a stable isotope, can thus be above, especially the phenothiazines and benzodiaze converted to a diagnostic for use herein. Put another pines and their analogues. Among the narcotic analge way, any compound of formula () of this invention sics, there can be mentioned in particular the metha which can have incorporated into its structure such a done-type and meperidine-type compounds specified radio-active or stable isotope either directly or through hereinabove. Among the cerebral stimulants, there can 55 incorporation of the isotope into the structure of the also be mentioned the many specific compounds set corresponding compound of formula (II) can be used forth hereinabove, particularly the sympathomimetic for diagnostic purposes. amine-type cerebral stimulants and the tricyclic antide It will be apparent from the known structure of the pressants, especially preferred tricyclics being the many drug species exemplified above, that in many dibenzazepines and dibenzoxapines and their analogues. 60 cases the selected drug will possess more than one reac Also illustrative of the centrally acting drug species tive functional group, and, in particular, that the drug containing primary, secondary or tertiary amine groups may contain hydroxyl or carboxyl or other functional contemplated by this invention are centrally active groups in addition to the amino group or groups which metabolites of centrally acting drugs. Such metabolites is/are to be replaced with the redox system, and that are typified by hydroxylated metabolites of tricyclic 65 these additional groups will at times benefit from being antidepressants, such as the E- and Z-isomers of 1 protected during synthesis and/or during administra hydroxynortriptyline, 2-hydroxyimipramine, 2-hydrox tion. The nature of such protection is described in more ydesipramine and 8-hydroxychloripramine; and hy detail below. Obviously, such protected drug species 5,082,853 17 18 are encompassed by the definition of "drug' set forth hereinabove. OH By "residue of a centrally acting primary, secondary YO or tertiary amine" as used herein there is meant that CHCH2 portion of the centrally acting amine which would re main after removal of the respective primary, second YO ary or tertiary amino group therefrom, e.g., in the case of phenethylamine, which has the structural formula wherein each Y is defined as above. As a further exam ple, one can mention the tertiary amine phenothiazine 10 tranquilizers/antipsychotics, acepromazine and aceto phenazine, which have the structures CHCHNH2, HCH-CHNCH). the corresponding residue would be 15

S

20 and

In the case of centrally acting amines which also con tain one or more hydroxy groups and/or one or more HCH-CHN N-CH2CH2OH, carboxy functions, the residue thereof may contain one 25 or more of those hydroxy and/or carbox functions in protected form. Thus, for example, when the centrally acting primary amine is levodopa, which has the struc OCOS tural formula 30 respectively, and which have the same residue, i.e. HO CH2- (H-NH. COOH H.CHCH HO 35 the corresponding residue would be CCOS It will also be apparent from the foregoing that the YO CH-CH exact structure of the amino function in the centrally COOY acting amine/parent drug is immaterial insofar as con YO cerns the structure of the instant compounds of formu las (I) and (II), for in formulas (I) and (II) the entire wherein each Y is hydrogen or a hydroxyl protective amino function in the parent drug has been replaced group as defined hereinabove (typically, acyl or carbon 45 with a dihydropyridine/pyridinium salt redox system. ate) and Y is hydrogen or a carboxyl protective group Thus, virtually any centrally acting primary amine D as defined hereinabove (typically, C1-C alkyl). NH2, secondary amine D-NHR1 or tertiary amine D It will be apparent from the foregoing that differedit NR2R3 can provide the drug residue D- in the instant centrally acting primary, secondary and/or tertiary compounds. Without being limited to specific defini amines may have the same residue as defined herein and tions of the R1,R2 and R3 groups in the secondary and as represented by D in formulas (I) and (II). Thus, for tertiary amines, the following definitions of illustrative example, desipramine, which is a tricyclic antidepres radicals are given: sant having a secondary amine function, and imipra R can be alkyl, preferably C1-C10 alkyl; cycloalkyl, nine, which is a tricyclic anti-depressant having a ter preferably C3-C8 cycloalkyl; alkenyl, preferably tiary amine function, both have the same residue, i.e. 55 C2-C10 alkenyl; cycloalkenyl, preferably C3-C8 cy cloalkenyl; or aryl, preferably C6-C10 aryl, particularly phenyl. Any of the foregoing R1 radicals can optionally be substituted by one or more (typically 1 to 3) substitu ents which may be the same or different. Possible sub stituents on the alkyl and alkenyl radicals include N C6-C10 aryl; hydroxy: hydroxy(lower alkyl)amino: sub stituted C6-C10 aryl wherein the substituent(s) is/are selected from the aryl substituents defined below; Similarly, norepinephrine and epinephrine, which are 65 C3-Cs cycloalkyl; substituted C3-C8 cycloalkyl wherein adrenergic agents and have a primary amino group and the substituent(s) is/are selected from the cycloalkyl a secondary amino group, respectively, share the same substituents defined below: halo: lower alkoxy; lower residue, i.e. alkylthio; lower alkylsulfinyl; lower alkylsulfonyl; 5,082,853 19 20 clude dimethylamino, 4-(2-phenylamino)ethyl)pipera zin-1-yl, piperidino, pyrrollidin-1-yl, 4- (3'-chloro phenyl)piperazin-1-yl, 4-methylpiperazin-1-yl, 4-(2'- -NHCCC-Clo alkyl); and -OC(C1-C10 alkyl). hydroxyethyl)piperidino, 4-(2-hexadecanoyloxy)e- Possible substituents on the aryl radicals include lower thylpiperidino, 4-(2'-hydroxyethyl)piperazin-1-yl, 4 alkyl, halo, lower alkoxy, carbamoyl, lower alkoxycar 2'-(N-methylcarbamoyl)ethyl-piperazin-1-yl, pipera bonyl, lower alkanoyloxy, lower haloalkyl, mono(- zin-1-yl, (N-benzyl-N-methyl)amino, diethylamino, lower alkyl)amino, di(lower alkyl)amino, monolower morpholino, (4-carbamoyl-4-piperidino)piperidino, (N- alkyl)carbamoyl, lower alkylthio, lower alkylsulfinyl methyl-N-phenethyl)amino and 4-(2'-acetoxyethyl)pip and lower alkysulfonyl. Possible cycloalkyl substituents 10 erazin-1-yl. include lower alkyl; C6-C10 aryl; substituted lower The expression "non-toxic pharmaceutically accept alkyl wherein the substituent(s) can be any of the alkyl able salts' as used herein generally includes the non substituents defined above; substituted C6-C10 aryl toxic salts of compounds of formula (I) formed with wherein the substituent(s) can be any of the aryl substit nontoxic, pharmaceutically acceptable inorganic or uents defined above; halo: lower alkoxy; lower alkyl 15 organic acids HX. For example, the salts include those thio; lower alkylsulfinyl; lower alkylsulfonyl; derived from inorganic acids such as hydrochloric, hydrobromic, sulfuric, sulfamic, hydrochloric, hydro bromic, sulfuric, sulfamic, phosphoric, nitric and the 20 like; and the salts prepared from organic acids such as -NHCCC-Cio alkyl); and -OC(C1-C10 alkyl). acetic, propionic, succinic, glycolic, stearic, lactic, Preferred secondary amino groups -NHR1 are lower a malic, tartaric, citric, ascorbic. panoic, maleic, hydrox amino unsubstituted or substituted by hydroxy or hy ymaleic, phenylacetic, glutamic, benzoic, salicylic, sul droxy (lower alkyl)amino and phenylamino. Particu fanilic, fumaric, methanesulfonic, toluenesulfonic and larly preferred secondary amino groups include me 25 the like. The expression "anion of a non-toxic pharma thylamino, phenylamino, tert-butylamino, iso ceutically acceptable acid' as used herein, e.g. in con propylamino, n-butylamino, ethylamino, 2-hydroxye nection with structure (II), is intended to include anions thylamino and 2-(2'-hydroxyethylamino)ethylamino. of such inorganic or organic acids HX. R2 and R3, which can be the same or different, can each It too will be appreciated that the radical represented be any one of the R radicals defined above, or R2 and 30 by R3 can be combined such that -NR2R3 represents a saturated monocyclic tertiary amino group, preferably derived from a secondary amine monocycle having 5 to 7 ring atoms, optionally containing another hetero atom -) (-O-, -S- or -N-) in addition to the indicated 35 nitrogen atom, and optionally bearing one or more (typically 1 to 3) substituents such as lower alkyl, substi in formula (I) must enable the compound of formula (I) tuted lower alkyl, C6-C10 aryl, substituted C6-C10 aryl, to penetrate the BBB and must also be capable of being saturated monocyclic tertiary amino and carbamoyl. oxidized in vivo to the corresponding quaternary struc The substituted lower alkyl groups include alkyl groups 40 ture. The ionic entity which results from such in vivo substituted by one or more (typically 1 to 3) C6-C10 oxidation is prevented from efflux from the brain, while arylamino, hydroxy, C2-C20 akanoyloxy, mono(lower elimination from the general circulation is accelerated. alkyl)carbamoyl, C6-C10 aryl or any of the other alkyl in contradistinction to the drug-carrier entities dis substituents defined in connection with R1 above. The closed, for example, in Science, Vol 214, Dec. 18, 1981, substituted aryl groups include aryl groups substituted 45 pp. 1370-1372, however, there is no readily metaboli by one or more (typically 1 to 3) substituents which can cally cleavable bond between drug and quaternary por be halo or any of the other aryl substituents defined in tions, and the active species delivered in the present connection with R above. Illustrative of saturated monocyclic tertiary amine groups encompassed by the case is not the original drug from which the compound -NR2R3 term are morpholino, 1-pyrrolidinyl, 4-ben 50 of formula () was derived, but rather is the formula (II) zyl-1-piperazinyl, perhydro-1,2,4-oxathiazin-4-yl, 1- or quaternary itself. 4-piperazinyl, 4-methyl-1-piperazinyl, piperidino, hex It will also be appreciated that a compound of for amethyleneimino, 4-phenylpiperidino, 2-methyl-1- mula () may be administered as the free base or in the pyrazolidinyl, 1- or 2-pyrazolidinyl, 3-methyl-1- form of a non-toxic pharmaceutically acceptable salt imidazolidinyl, 1- or 3-imidazolidinyl, 4-benzyl 55 thereof, i.e. a salt which can be represented by the for piperidino and 4-phenyl-l-piperazinyl. Preferred ter mula tiary amine groups encompassed by -NR2R3 include di(lower alkyl)amino; N-lower alkyl-N-benzylamino; N-lower alkyl-N-phenethylamino; piperidino; pyrroli din-1-yl: piperazin-1-yl; morpholino; piperidino substi D-) tuted in the 4-position by hydroxy-substituted lower alkyl, C2-C-20 alkanoyloxy-substituted lower alkyl, carbamoyl or piperidino; and piperazin-1-yl substituted wherein D, in the 4-position by lower alkyl, C2-C20 alkanoyloxy substituted lower alkyl, lower monoalkylcarbamoyl 65 substituted lower alkyl, hydroxy-substituted lower al kyl, phenylamino-substituted lower alkyl or halo -NO phenyl. Especially preferred -NR2R3 groupings in 5,082,853 21 22 and HX are defined as before; and that, regardless of the centrally acting amine/parent drug is an antitumor/an actual form in which the compound is administered, it ticancer agent, the instant redox system is employed to will be converted in vivo to a quaternary salt of formula elicit an antitumor/anticancer response; when the par (II), the anion X being present in vivo. It is not neces ent drug is a sympathetic stimulant, the instant redox sary that the anion be introduced as part of the com- 5 system is used to elicit a sympathetic stimulant or am pound administered. Indeed, even when the compound phetamine-like response; when the parent drug is of formula () is used in its salt form, the anion of the GABA or a related compound, the instant redox system formula (II) compound is not necessarily the same as is used to elicit an antiepileptic/anticonvulsant or anal that present in the formula (I) compound. Indeed, the gesic response; when the parent drug is a tranquilizer, exact identity of the anionic portion of the compound of 10 the instant system is used to elicit a tranquilizing re formula (II) is immaterial to the in vivo transformation sponse; when the parent drug is an antidepressant, the of (I) to (II). instant system is used to elicit an antidepressant re In a presently preferred embodiment of the present sponse; and so forth. invention, the centrally acting amine of which D is the With respect to the preferred embodiment referred to residue is dopamine and the instant redox system is thus 15 above, with dopamine as the parent amine, the catechol designed to elicit a sustained and brain-specific dopam moiety thereof in certain instances being acylated, e.g. inergic (e.g. anti-Parkinsonism or anti-hyperprolac acetylated or pivallated, and selecting tinenia) response in the animal to which the formula (I) derivative is administered: it is believed that this effect CONH2 is achieved via in vivo conversion of the formula (I) 20 compound to the pharmacologically active formula (II) quaternary, which is essentially "locked in' the brain. In analogous fashion, the instant redox system I-II in as-NC) , which D is the residue of any other centrally acting primary, secondary or tertiary amine is designed to 25 elicit the kind of pharmacological response which the following reaction scheme has been devised for would be obtained by delivery of the primary, second preparation of the formula (I) analogues: ary or tertiary amine itself to the brain, i.e. when the

SCHEME 3 (6."

(ÖrNO2 (Zincke reagent) --

OH OH CONH2 CONH2 triethylainine G Na2SO G nethanol NaHCO3 N+ ethyl acetate N H. H: H. H. CH2 CH NHHBr

OH OH

OH - OH pivaloyl chloride trifluoroacetic acid 5,082,853 23 24 -continued SCHEME-3 CONH2 CFCO- CONH2 Na2S2O4. NaHCO3 G N+ ethyl acetate N GH: H. CH CH

OCOC(CH3)3 OCOC(CH3)3 OCOC(CH3)3 OCOC(CH3)3

OH OH

H. H. NH.HBr pivaloyl chloride trifluoroacetic acid Inaeic acid

OCOC(CH3)3 --Zincketriethylamine reagent G CONH 2 Na2SOa2S2O4. G CONH2 OCOC(CH3)3 methanol NaHCO3 ethyl acetate Ci -- CH2 CH CH COOH 2 2 H. ?h CH CH2 NH2. CH YoooH

OCOC(CH3)3 OCOC(CH3)3 OCOC(CH3)3 OCOC(CH3)3 An alternate reaction Scheme for preparation of the dopamine analogues is depicted below. r

SCHEME 4 OH CONH2 CONH2 CONH2 OH -- Na2S2O G Br. NaHCO3 G N +N ethyl N acetate H. H. H. H: CH2 CH2 B

OH OH OH OH pivaloyl chloride trifluoroacetic acid 5,082,853 25 26 -continued SCHEME 4 OCOC(CH3)3 OCOC(CH3)3 CONH2 CONH2 CONH2 Na2S2O4 -- G fiérie N +N Br ethyl N acetate H: H. H. CH CH2 CH2 Br 9- (9- Similar schemes can be shown for the preparation of the other compounds of the invention. The acylation will not use the parent secondary or tertiary amine as step, which introduces the hydroxyl protecting groups, 20 the starting material but would instead use the corre is only needed when there are hydroxyl groups which it sponding primary amine as the starting material. Alter is desired to protect. Moreover, when carbonate rather natively, a compound of the formula than acyl protecting groups are desired, the step of introducing the protecting groups will involve reacting D-Hall the hydroxy-containing compound with a halocarbon 25 wherein Hal is chloro or bromo and D is the residue of ate of the type Y'OCOCl or Y'OCOBr (formed by reac a centrally acting primary, secondary or tertiary amine tion of Y'OH with COCl2 or COBr2), rather than with can be reacted with nicotinamide or the like (as de an acyl halide YCl or YBr, Y and Y being as generi picted in Scheme 4) to afford to desired compounds of cally defined hereinabove expect that here neither Y the invention, regardless of whether the parent drug is nor Y' can be hydrogen. Also, as shown in Schemes 3 30 a primary, secondary or tertiary amine. and 4, the order of steps may be altered; quaternization, various illustrative synthetic schemes as applied to followed by reduction, need not always constitute the specific compounds of the invention are set forth below final two steps but may be carried out earlier in the in the section entitled "Illustrative Synthetic Methods'. reaction sequence. Yet other reaction schemes, reac While the sequence of reaction steps can be varied in tants, solvents, reaction conditions, etc. (e.g. using an 35 many cases, in general the final step (except in the case anhydride rather than an acyl halide for the acylation of optional salt formation or possibly in the case of step, or preparing a different acyl derivative, e.g. the radiolabeling will be reduction of a quaternary com acetyl rather than the pivalyl derivative, or using a pound of formula (II) to the corresponding dihydro different Zincke reagent for the exchange reaction) will compound of formula (). The reduction is usually con be readily apparent to those skilled in the art. Also, ducted at a temperature from about -10' C. to room insofar as concerns the quaternary compounds, when an temperature, for a period of time from about 10minutes anion different from the one obtained is desired, the to 2 hours, conveniently at atmospheric pressure. Typi anion in the quaternary salt may be subjected to anion cally, a large excess of reducing agent is employed, e.g., exchange via an anion exchange resin or, more conve a 1:5 molar ratio of reducing agent to starting com niently, by use of the method of Kaminski etal, Tetrahe 45 dron, Vol. 34, pp. 2857-2859 (1978). According to the pound of formula (II). The process is conducted in the Kaminski et al method, a methanolic solution of an HX presence of a suitable reducing agent, preferably an acid will react with a quaternary ammonium halide to alkali metal dithionite such as sodium dithionite or an produce the methyl halide and the corresponding qua alkali metal borohydride such as sodium borohydride or ternary .X salt. Moreover, the manner in which the lithium aluminum borohydride, in a suitable solvent. ultimate compound is prepared should be tailored to the Sodium dithionite reduction is conveniently carried out presence of any other reactive groups in the molecule. in an aqueous solution; the dihydro product of formula For example, when the parent amine contains one or (I) is usually insoluble in water and thus can be readily more carboxy functions, such functions will typically be separated from the reaction medium. In the case of esterified, e.g. converted to the corresponding ethyl 55 sodium borohydride reduction, an organic reaction ester, or otherwise suitably protected, usually prior to medium is employed, e.g., a lower alkanol such as meth formation of the quaternary compound. Thus, a wide anoi, an aqueous alkanol or other protic solvent. variety of synthetic approaches can be utilized, depend When a Zincke reagent is utilized in the reaction ing on the desired structure of the final produce. sequence, e.g. when Scheme 3 is employed, such rea The process exemplified in Scheme 3, i.e. reacting a 60 gent can be prepared by reacting 1-chloro-2,4-dinitro starting material containing an -NH2 group with a benzene with a compound of the formula Zincke reagent, can be used to derive the instant com pounds wherein D is the residue of a centrally acting H H primary amine directly from the corresponding cen N N trally acting primary amine/parent drugs. However, if 65 it is desired to prepare the instant compounds wherein D is the residue of a centrally acting secondary or ter ( DC I De tiary amine via the process shown in Scheme 3, then one (R) (R) 5,082,853 27 28 -continued -continued (R) H N

N (R) NO2 Cl wherein R, n, p and q are defined as with formula (I), to 10 afford the corresponding Zincke reagent of the formula

NO2 (R) respectively. Thus, for example, the specific Zincke 5 reagent depicted in Scheme 3 can be prepared by react ing nicotinamide with 1-chloro-2,4-dinitrobenzene. See also Zincke et al, Annalen, 1904, 333, 296; Lettré, An (6) malen, 1953, 579, 123; Keijzer et al, Hetrocycles, Vol. 16, No. 10, 1981, 1687. NO, C 20 In the case of radiodiagnostics, the synthetic method of choice generally involves introducing the radioactive element toward the end of the reaction sequence, rather than using the radiolabeled parent drug itself as the ONO2 starting material. Schemes 5 and 6 below are illustrative 25 of such instances of tailoring chemical synthesis to the (R) particular drug involved. Scheme 5 depicts synthesis of an analogue of I 123 labeled metaraminol; Scheme 6 depicts a synthetic route to radioiodinated benzylamine and phenethylamine analogues. (CIO)-- NOC or

ONO2

SCHEMES CONH2 CONH2 (6) CH3 CH3 N HO-CH-CH-NH2 C NO triethylamine G -- methanol C- OH OH NO2 NH2 Zincke reagent p-aminometaraminol HF NaNO2 N yo, 5,082,853 29 30 -continued SCHEME5 CONH2 CONH2 Hs (H, Ho-H-cH-N+ O C- Ho-cH-H-N+ O C NaI, HF

OH s

SCHEME 6 ar +N CONH2 NO + H2N (CH2)-NH2 -G H2N (CH2)-N'- O C C NO2 n = 1 (p-aminobenzylamine) n = 20p-aminophenethylamine) Zincke reagent HF NaNO2 N yo,

CONH2 CONH2 Na, HF

r-(o)-e-C O < 12- ---(o)-cis- O) c use. CONH2 r-(o)- (CH2)-N ) Suitable nontoxic pharmaceutically acceptable carri ers for use with the topic compounds of formula (I), e.g., those less toxic than the target drug species them- 65 carriers will depend upon the exact nature of the partic selves, will be apparent to those skilled in this art. Com- ular dosage form selected, as well as upon the identity pare, for example, Remington's Pharmaceutical Sciences, of the compound to be administered. The therapeutic 4th Edition (1970). Obviously, the choice of suitable dosage range for administration of a compound accord 5,082,853 31 32 ing to this invention will generally be the same as, or less than, those characteristically used in this art for Illustrative Synthetic Methods administration of the known primary, secondary or Method A tertiary amine/parent drug of which the instant com The primary amine is reacted with the Zincke rea pound is an analogue. Naturally, such therapeutic dos 5 gent of the formula age ranges will vary with the size of the patient, the condition for which the compound is administered, the particular dosage form employed, route of administra tion and the like. The quantity of given dosage form 10 (6." needed to deliver the desired dose will of course depend N+ upon the concentration of the compound of formula (I) in any given pharmaceutical composition/dosage form NO Cl thereof. Obviously, in the case of diagnostic agents, the dosage of formula (I) compound used will be a quantity 15 sufficient to deliver an amount of radioisotope, stable NO2 isotope or the like which can be effectively detected by radioimaging or other detection means. The amount of in the presence of a suitable base, e.g. triethylamine, in radioisotope, stable isotope or the like present in the 20 an appropriate organic solvent, e.g. methanol, to afford dosage form will be within or below the ranges conven the corresponding quaternary derivative of formula tionally used for diagnostic purposes. (I), which is then reduced by treatment with sodium The ability of the topic compounds to cross the BBB dithionite or sodium borohydride as generally described and to be "locked into' the brain allows administration hereinabove to afford the desired compound of formula 25 (I). in a site-specific manner. A combination of the present The representative primary amines listed below may dihydropyridine pyridinium salt redox system with a be derivatized in this manner to the corresponding pyri sustained release system will further enhance this site dinium and dihydropyridine analogues of this invention. specificity. Thus, a preferred embodiment of the inven The foregoing procedure may be repeated using a tion comprises formulating the compound of formula (I) Zincke reagent of the formula or its salt utilizing a sustained release carrier system 30 and/or route of administration capable of slowly releas ing the chemical, e.g., sustained release tablets and cap CONH2 sules for oral administration; subcutaneous injection, or implantation of drugs in solid pellet form (for example, 35 distributed in a biodegradable polymer); intramuscular injection of the compound in solution in oil or sus pended in a repository vehicle; a transdermal delivery device or form such as an ointment to be applied locally to the desired site (when the drug is susceptible of deliv (Ör C or (Ör C erythrough the skin), slow intravenous infusion and the like. The rate of release of compound from the sustained NO2 NO release system should be comparable to the rate of in prepared from picolinamide or isonicotinamide, respec vivo oxidation of the dihydro form of the redox system 45 tively, to convert primary amines such as those specifi in order to achieve the greatest degree of enhancement cally mentioned in connection with this method to the of specificity. corresponding quaternary and dihydro derivatives.

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5,082,853 47 48 The representative compounds listed below may be Method B derivatized in this manner to the corresponding quater This is a variation of Method A used when the parent nary and dihydro compounds. Omega amino acids in addition to GABA (which is shown below), other natu primary amine contains a -COOH function which is to ral amino acids such as glycine, aspartic acid and glu be protected. tanic acid, and small peptides (2-20 amino acids, e.g. The parent compound is first converted to the corre met-enkephalin and leu-enkephalin) may be similarly sponding ethyl or t-butyl ester by conventional esterifi derivatized. cation techniques. That ester is then used as the starting The picolinamide and isonicotinamide quaternary O and dihydro derivatives of the drugs specifically men material in Method A and that method is repeated. tioned for derivatizing according to this method may be Obviously, other esters may be similarly prepared in similarly prepared, using the appropriate Zincke rea the first step by use of other esterifying agents. gent. See Method A. 15

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5,082,853 59 60 tected quaternary, which may then be reacted with Method C trimethylacetyl chloride to form the protected quater This is a variation of Method A used when the parent nary. The protected quaternary may then be reduced to primary amine contains one or more OH functions the protected dihydro compound as in Method A. which are to be protected. Various other hydroxy protecting groups may be The drug is first reacted with excess trimethylacetyl introduced in similar fashion. chloride, under strongly acid conditions, to convert the The representative drugs listed below may be deriva hydroxy group(s) to pivalyloxy group(s). That pro tized in this manner to the corresponding quaternary tected derivative is then used as the starting material in and dihydro compounds. The corresponding picolina Method A and that method is repeated. Alternatively, 10 mide and isonicotinamide quaternary and dihydro de the first two steps may be reversed, i.e., the drug may be rivatives may be similarly prepared, using the appropri first reacted with the Zincke reagent to form the unpro ate Zincke reagent See Method A.

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5,082,853 63 64 sequence considered most convenient. The amine func Method D tion is derivatized according to Method A. This variation of Method A can be used when the The representative drugs listed below may be deriva tized in this manner to the corresponding quaternary drug contains one or more OH and COOH functions and dihydro compounds. The corresponding picolina which are to be protected. The protecting groups, typi mide and isonicotinamide quaternary and dihydro de cally the ethyl or t-butyl ester and pivalyloxy groups, rivatives may be similarly prepared, using the appropri are introduced as described in Methods B and C, in the ate Zincke reagent. See Method A. 10

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SO

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5,082,853 67 68 Similarly, Method E may be combined with Methods Method E B, C or D to afford the corresponding 3-quinolinecar Method A is followed, using a Zincke reagent of the boxamide derivatives, e.g. of the drugs listed with those formula methods. The foregoing procedure may be repeated using a Zincke reagent of the formula N-CONH2 CONH2 al N -- 1 N NO Cl a -O- C NO2 NO2 1 derived from 4-isoquinolinecarboxamide, in place of the prepared from 3-quinolinecarboxamide, in place of the Zincke reagent shown above, to convert drugs such as Zincke reagent shown in Method A. those mentioned with Methods A, B, C, or D to the The representative starting materials listed below corresponding 4-isoquinolinecarboxamide derivatives. may be derivatized in this manner to the corresponding 2O The general procedures depicted above may be uti quaternary and dihydro compounds, as may the remain lized to provide the 1,2-dihydro derivatives as well as ing drugs listed with Method A. the depicted 1,4-dihydros.

STARTING QUATERNARY DHYDRO MATERIAL INTERMEDIATE(CATION) DERVATIVE

CONH2 ob CH-CH-NH2 CONH2 N / 7 W CH-nm-CH-N C CH-CH-N-h N / H2 N / C TRANYLCYPROMINE i. H2

NH2 N CONH2 CONH2

a AMANTAONE ? N+ ? N

CHHCHNH ()-alpa ()-alia N+ N

AMPHETAMINE OCla1 NoonH, OOl CONH2

NH2CH2CH2

PHENYLETHYLAMINE NCH2CH2 NCH2CH2 A. CONH2 CONH2 5,082,853 69 70 -continued STARTING QUATERNARY DHYDRO MATERIAL INTERMEDIATE(CATION) OERIVATIVE

wn wn n N N N CONH2 CONH2 N N N a al a mom NH-NH2 NH-N ?t \ NH-N HYDRALAZINE

CHHCH ()-algal ()-age NH N+ N 2 d-isomer d-isomer d-isomer OEXTROAMPHETAMINE -- N CHHCH, ()-algal ()-alga NH2 N+ N+ 2 isomer l-isomer -isoner LEVAMPHETAMINE - N - CONH2 CONH2 H. CONH2 CONH2 CH-C-NH2 2 CH 3 / \ CHs far CH3 CH-i-N: ch,--N PHENTERMINE O CH3 O CH3

45 -continued

CHHCHN Method F 50 An ether solution of a compound of formula (I) is treated with an equivalent amount of anhydrous p-tol- fro CONH2 uenesulfonic acid and dissolved in dry ether. Mixing at (from amphetamine) room temperature is continued until the imminium salt CONH2 precipitates out of solution. The salt is then removed by 55 CH filtration. 3. Imminium salts which may be prepared in this man- CH-C-N ner include those derived from the following com- th3 we pounds of the invention: 60 (from phentermine)

N-CH2CH2 Method G 65 The compounds of formulas (I) and (II) correspond CONH2 ing to the secondary amines/parent drugs listed below (from phenethylamine) are prepared by selecting the corresponding primary amines as the starting materials and following Method 5,082,853 71 72 C described hereinabove. Thus, the hydroxy groups are nicotinamide derivatives may be similarly prepared, first protected, the protected primary amines are then using the appropriate Zincke reagents, as described in reacted with the Zincke reagent to afford the quater nary derivatives and the quaternaries are then reduced Method A. to afford the desired compounds of formula (I). Method E described hereinabove may be combined Different protecting groups from those shown may with Method G to afford the corresponding 3 be introduced in a similar manner. quinolinecarboxamide and 4-isoquinolinecarboxamide The picolinamide and isonicotinamide quaternary derivatives, e.g. of the parent drugs listed with this and dihydro derivatives corresponding to the depicted method. O

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5,082,853 75 76 Method H or 4-quinolinecarboxamide in place of the compounds of formulas (I) and (II) corresponding to parent drugs The compounds of formulas (1) and (II) correspond ing to the secondary and tertiary amines/parent drugs such as those specifically mentioned below. listed below are prepared by selecting the correspond When the parent secondary and tertiary amines con ing compounds of the formula tain OH and/or COOH groups in need of protection, suitable protecting groups can be introduced before or D-Hal after formation of the quaternary derivatives. See, for example, Scheme 4 and Methods B, C and D herein as the starting materials, reacting those starting materi O als with nicotinamide to afford the quaternary interme above. diates and then reducing the quaternaries with Na2S2O4 Method H can also be employed to prepare the com to afford the desired dihydro derivatives. pounds of formulas (I) and (II) corresponding to the The foregoing procedure may be repeated using primary amines listed in Methods A through E; see, for picolinamide, isonicotinamide, 3-quinolinecarboxamide 15 example, Scheme 4.

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5,082,853 ZHNOOCHNOO panu?uoo

5,082,853 87 88 CHNOO

| HO*

5,082,853 123 124 5,082,853 125 126

ponu?uoo

5,082,853 131 132

ponu?uoo 5,082,853 133 134

ponu?uoo 5,082,853 135 136

panu?uoo 5,082,853 137 138

5,082,853 141 142 In order to further illustrate the present invention and the advantages thereof, the following specific examples Example 3 are given, it being understood that same are intended as Preparation of illustrative and in nowise limitative. 1-(3,4-Dipivaloyloxy)phenethyl-3-carbamoyl Example 1 pyridinium Trifluoroacetate Preparation of 1-(3,4-Dihydroxy)phenethyl-3-carbamoylpyridinium -(3,4-Dihydroxy)phenethyl-3-carbamoylpyridinium chloride monohydrate (350 mg, 1.12 mmol) is dissolved Chloride in trifluoroacetic acid (5 ml) under nitrogen at room O temperature. Pivaloyl chloride (0.3 ml, 24 mmol) is The Zincke reagent, 1-(2,4-dinitro)phenyl-3-car added dropwise to the stirred solution. Stirring is con bamoylpyridinium chloride (3.56 g, 0.01 mole), in meth tinued for one hour, after which time volatile material is anol (10 ml), is added over a 10 minute period to a removed under reduced pressure, leaving an oily resi mixture of dopamine hydrobromide (2.34g, 0.01 mole) due. Extensive trituration with ethyl ether gives a fine and triethylamine (1.4 ml, 0.01 mole) in methanol (20 5 white powder, which is collected by filtration and ml). A deep red color is immediately observed. The washed with additional ethyl ether. Yield 410 mg, 67%. reaction mixture is stirred and heated at gentle reflux. The product is further characterized by the structural After approximately 10 minutes, the red color begins to formula: fade and precipitation of a yellow solid commences. Forty minutes later, the yellow product is collected by 20 CONH2 filtration. Recrystallization from a mixture of methanol and ethyl ether gives a pale cream powder melting at O 246-248 C. Yield 1.9 g, 73%. The product has the (CH3)3CCO CH-CH-N+ O. CFCO. structural formula 25 CONH2 ocCH.) O

30 Example 4 -(e)- O) Ci Preparation of HO 1-(3,4-Dipivaloyloxy)phenethyl-3-carbamoyl-1,4-dihy dropyridine as confirmed by NMR and UV. Substitution of an equivalent quantity of 1-(3,4- Example 2 35 dipivaloyloxy)phenethyl-3-carbamoylpyridinium tri Preparation of fluoroacetate for the 1-(3,4-dihydroxy)phenethyl-3-car 1-(3,4-Dihydroxy)phenethyl-3-carbamoyl-1,4-dihy bamoylpyridinium chloride used in Example 2 and sub dropyridine stantial repetition of the procedure detailed in that Ex 1-(3,4-Dihydroxy)phenethyl-3-carbamoylpyridinium 40 ample affords the desired product of the formula: chloride (430 mg, 15 mmol), is added to 100 ml of an ice-cold, aqueous solution of sodium bicarbonate (7.6 g, CONH2 90 mmol), sodium dithionite (13.75 g, 80 mmol) and O ed ethyl acetate (60 ml). Nitrogen is bubbled into the mix 45 ture throughout the reaction. Addition of the pyridin CH3)3CCO CH-CH-N ium chloride starting material causes a yellow color to develop. Stirring is continued and the reaction mixture is maintained at approximately 0' C. for about one and O one-half hours, after which time the ethyl acetate and aqueous layers are separated and the aqueous layer is extracted four times with 50 ml portions of ethyl ace Example 5 tate. The combined organic layers are dried over anhy Preparation of (3,4-Dipivaloyloxy)phenethylamine drous magnesium sulfate and evaporated to dryness Maleinate under reduced pressure. The soft yellow solid (280 mg, 55 75%) which remains is rapidly oxidized by methanolic Dopamine hydrobromide (11.7 g) is suspended in silver nitrate at room temperature. Based on NMR spec trifluoroacetic acid (117.5 ml) and pivaloyl chloride tra and UV and high resolution mass spectroscopy, the (13.65 ml) is added dropwise under argon. After one product is assigned the structural formula half hour, water (0.75 ml) is added and solventis evapo 60 rated under vacuum. The residue is dissolved in chloro form (200 m) and washed, first with water, then with CONH2 cold sodium bicarbonate solution then again with water. The resultant solution is dried over anhydrous sodium sulfate and evaporated under vacuum. The residual oil 65 is dissolved in 2-propanol (25 ml) and maleic acid (5.8 g) -O-o- ) . in warm 2-propanol (30 ml) is then added. Ethyl ether HO (100 ml) is added and the mixture is refrigerated at O' C. overnight. The product is removed by filtration. Yield 5,082,853 143 144 3.8g, m.p. 146'-8" C. The product is further character ized by the structural formula: Example 9 Preparation of O O 3-Carbamoyl-1-(3'-carboxy)propylpyridinium Chloride 5 The Zincke reagent prepared as in Example 8 (3.56 g, (chicko CH2-CH2-NH2. c--OH. 0.01 mol) is dissolved in methanol (10 ml) and added -c-oh slowly to a solution of ethyl 4-aminobutyrate hydro OCC(CH3)3 chloride (1.67 g, 0.01 mol) in methanol (20 ml). The O deep red color of the resultant solution fades to a light orange color with stirring. The mixture is heated to a gentle boil and allowed to reflux for 30 minutes, then is Example 6 stirred overnight. Crystals of dinitroaniline (10 g) are Preparation of 1-(3,4-Dipivaloyloxy)phenethyl removed by filtration and the filtrate is evaporated to 15 dryness. Recrystallization from a mixture of methanol -3-carbamoylpyridinium Chloride and ethyl ether affords an orange product, which is Substitution of an equivalent quantity of (3,4- assigned the following structure on the basis of NMR dipivaloyloxy) phenethylamine maleinate for the dopa spectra and elemental analysis: mine hydrobromide used in Example 1 and substantial repetition of the procedure detailed in that Example 20 affords the desired product of the formula: CONH2

CONH2 O I 25 (CH3)3CC CH-CH-N+O C-. Example 10 ocCH). Preparation of ... O 30 3-Carbamoyl-1-(3'-ethoxycarbonyl)propylpyridinium Chloride Example 7 The free acid product of Example 9 is suspended in Preparation of 1-(3,4-Dipivaloyloxy)phenethyl ethanol. HCl gas is bubbled through the suspension at O' 35 C. for 45 minutes. The reaction mixture is refluxed for -3-carbamoyl-1,4-dihydropyridine one hour, then allowed to cool to room temperature, Substitution of an equivalent quantity of 1-(3,4- producing a white precipitate. Removal of the precipi dipivaloyloxy)phenethyl-3-carbamoylpyridinium chlo tate and evaporation of the solvent produces a yellow ride for the 1-(3,4-dihydroxy)phenethyl-3-carbamoyl oil, which is dissolved in a minimum amount of acetoni pyridinium chloride employed in Example 2 and sub trile, filtered and dried. Thin layer chromatography stantial repetition of the procedure there detailed af. reveals the presence of one product, which is assigned fords the desired product of the structural formula: the following structure on the basis of IR, UV and NMR spectra: CONH2 45 O (CH3)3CCO CH-CH-N a- (O +N CH2 COOCH2CH3. N / N ocCH) CH2 CH2 Example 11 Example 8 Preparation of Preparation of 55 3-Carbamoyl-1-(3'-ethoxycarbonyl)propyl-1,4-dihy 1-(2,4-Dinitro)phenyl-3-carbamoylpyridinium Chloride dropyridine 1-Chloro-2,4-dinitrobenzene (20g) is fused with nico 3-Carbamoyl-1-(3'-ethoxycarbonyl)propyl tinamide (8 g) on a steam bath for one hour. The ho pyridinium chloride (500 mg, 1.66 mmol) is dissolved in mogenous dark orange glassy material which results is cold deaerated water and maintained under nitrogen at dissolved in methanol (100 ml), with heating. Ethyl O' C. Sodium bicarbohate (0.84g, 9.96 mmol) is added, ether (400 ml) is added and a sticky yellow precipitate followed by sodium dithionite (1.16 g. 6.64 mmol). forms. The ether is removed, and the residue is washed Ethyl acetate is added and the mixture is stirred at 0°C., again in the same way. Then, the residue is dissolved in under nitrogen, for approximately one and one-half water (200 ml), with heating. Activated charcoal is 65 hours. Separation of the phases and drying of the or added and the mixture is refluxed for 5 minutes and ganic layer affords 0.15 g (39% yield) of a yellow oil. filtered. A yellow glassy product, the desired Zincke The following structure is assigned to the product on reagent, forms upon evaporation of the solvent. the basis of UV and NMR spectra: 5,082,853 145 146 identical to the corresponding portion of the centrally acting amine from which D can be considered to be derived. Preferred groups of compounds in this subclass O CONH2 include the following: 5 N CH2 COOCH2CH3. (1) Cerebral stimulants, including sympathomimetic N / N / amine-type cerebral stimulants, such as amphetamine, CH2 CH2 dextroamphetamine levamphetamine, levamphetamine, aletamine, cypenamine, phenlermine, methamphet Example 12 10 amine, fencamfamin, fenozolone, Zylofuramine, phen ethylamine, prolintane, thozalinone, etryptamine and Preparation of tranylcypromine; tricyclic antidepressant-type cerebral 3-Carbamoyl-1-(3'-ethoxycarbonyl)propylyridinium stimulants, especially dibenzazepines,dibenzoxepines Bromide and their analogues, e.g. desipramine, nortriptyline, Nicotinamide (7.32 g, 0.06 mol) is dissolved in di protriptyline, maprotiline, octriptyline, amitriptyline, methylformamide and ethyl 4-bromobutyrate (17.16 ml 5 imipramine, opipramol, doxepin, cidoxepin, amoxapine, 0.12 mol) is added dropwise. The reaction mixture is azipramine, butriptyline, clomipramine, dibenzepin, brought to the reflux temperature and then maintained dothiepin, intriptyline, ketipramine, melitracen and at that temperature for 3 hours. The solution is then allowed to cool to room temperature and stirred for 24 trimipramine; and many other cerebral stimulants, alert hours. The solvent is evaporated and the residue is 20 ing agents and anti-depressants of various types, as ex washed with ethanol, separated by filtration and dried emplified by thiothixine,dimethazan, doxapram, gam in a vacuum oven. Obtained in this manner is a white fexine, clodazon, amedalin, bupropion, cartazolate, powder (6.2 g), melting at 121-123' C. and having the daledalin, cyclindole, difluanine, fantridone, flubanilate, structure iprindole, modaline, pirandamine, pyrovalerone, tanda 25 mine, thiazesin, amiphenazole, trazodone and trebenzo (2) Anticancer or antitumor agents, e.g. daunamycin, doxorubicin. bactobolin, mitoxantrone and nimustine - O and the like; +N CH2 COOCH2CH3, 30 (3) Antiviral agents, e.g. amantadine, 5-amidino-2-(5- Nch1"n CH;1 amidino)-2-benzofuranyl)indole, 4,6-diimidazolino-2- phenylbenzo(b)thiophene, 2-guanidino-4,5-di-n- as confirmed by elemental analysis and UV, IR and propyloxazole, 2-guanidino-4,5-diphenyloxazole, glu NMR spectra. cosamine, 6-amino-6-deoxy-D-glucose, 6(hydrox Example 13 35 yimidazol-2-amine and the like; Preparation of (4) Neurotransmitters, e.g. tryptamine, dopamine, 3-Carbamoyl-1-(3'-ethoxycarbonyl)propyl-1,4-dihy tyramine, somatostatin, vasopressin, serotonin and his dropyridine tamine; (5) Hypotensives, including £8-adrenergic blockers, 3-Carbamoyl-1-(3'-ethoxycarbonyl)propyl 40 pyridinium bromide (500 mg) is dissolved in 10 ml of e.g. propranolol, metoprolol, nadolol, timolol and deaerated ice cold aqueous ethanol (20%). Sodium bi atenolol; and other hypotensives, e.g. hydralazine, gua carbonate (0.80 is added, followed immediately by so nethidine, prizidilol, bethanidine and debrisoquin; dium dithionite (1.10 g). Ethyl acetate is then added and (6) Analgesics, including phenothiazine-type analge the resultant yellow solution is stirred for one and one 45 sics such as methotrimeprazine. and narcotic analgesics, half hours in an ice bath. Chloroform is added and the particularly those of the meperidine-type, e.g. anileri organic layer is dried over anhydrous sodium sulfate dine, tilidine, phenampromide and piminodine, and and evaporated. The resultant yellow oil is assigned the those of the methadone-type, e.g. methadone, levome structure thadyl acetate,dextronoramide, propoxyphene, carbi phene, pyrroliphine and noracymethadol; (7) Sedatives, tranquilizers, hypnotics, antipsychotics, CONH2 anticonvulsants, including benzodiazepines and their analogues, used, for example, as sedatives, hypnotics, O anticonvulsants, and tranquilizers, e.g. perlapine, cloza CH2 COOCH2CH3 CH1 na -- 1 pine, flurazepam, adinazolam, flumezapine, metiapine CH2 55. and chlordiazepoxide; thioxanthine calming agents, e.g. based on UV and NMR spectra and elemental analysis. chlorprothixine; muscle relaxants, e.g. cyclobenzaprine; The present invention can thus be seen to provide phenothiazines and their analogues, used, for example, two major classes of novel chemical compounds, i.e. the as tranquilizers and antipsychotics, e.g. chlorpromazine, compounds of general formula (I) above, including 60 propiomazine, perphenazine, trifluoperazine, proma their salts, and the compounds of general formula (II) zine, triflupromazine, acetophenazine, butaperazine, above, wherein D is the residue of a centrally acting carphenazine, fluphenazine, prochlorperazine, thiopro primary, secondary or tertiary amine and the other pazate, piperacetazine, pipotiazine palmitate, aceproma structural variables are as defined broadly above. zine, loxapine, clomacran, clopenthixol, clothiapine, Within each of these major classes, the following sub- 65 clozapine, dimeprozan, perlapine and pinoxepin; other classes are particularly noteworthy: antipsychotics, e.g. pipamperone; other sedatives and (A) Compounds of formulas (I) and (II) wherein the hypnotics, such as benzoctamine and tracazolate; and D portion of the compound of formula (I) or (II) is other anticonvulsants, such as tiletamine and atolide; 5,082,853 147 148 (8) LHRH and its analogues containing a primary, D in formula (I) or (II) contains, in place of at least one secondary or tertiary amino group; of the -OH functional groups and at least one of the (9) Antibiotics, e.g. bacampicillin, pivampicillin and -COOH functional groups in said amine, at least one the like: and -OY group and at least one -COOY' group, respec (10) Diagnostics, especially radiopharmaceuticals, tively, wherein Y is a hydrolytically or matabolically such as radioiodinated p-iodometaraminol, radioiodin cleavable hydroxyl protective group and Y" is a hydro ated p-iodobenzylamine, radioiodinated p-iodophene lytically or metabolically cleavable carbosyl protective thylamine and radioiodinated p-iodo-N-isopropylam group. Within subclass (D), preferred compounds are phetamine. those wherein Y is an acyl group or a carbonate group Especially preferred compounds in subclass (A) are 10 and/or Y' is C1-C, alkyl. Of particular interest are the those in which D is the residue of a compound encom compounds in which D is a protected residue of a hypo passed by groups (1) and (7) above, particularly the tensive, e.g. methyldopa; a sympathetic stimulant, e.g. tricyclic antidepressants. levodopa; a hydroxy-containing amino acid, e.g. threo (8) Compounds of formulas() and (II) wherein the nine, tyrosine or serine, or a peptide containing such an centrally acting amine from which D can be considered 15 amino acid, e.g. leu-enkephalin, met-enkephalin, y to be derived also contains at least one -COOH func endorphin, 3-endorphin, a-endorphin, other enkephalin tional group, and D in formula (I) or (II) contains, in or endorphin, or an analogue of LHRH containing a place of at least one of the -COOH functional groups COOH group, a primary, secondary or tertiary amino in said amine, at least one -COOY' group wherein Y." function and a hydroxy-containing amino acid. Pre is a hydrolytically or metabolically cleavable carboxyl 20 ferred peptides contain 2 to 20 amino acid segments. protective group Within subclass (B), preferred com While the invention has been described in terms of pounds are those in which Y is C1-C7 alkyl and/or various preferred embodiments, the skilled artisan will wherein D is the residue of an amino acid (especially a appreciate that various modifications, substitutions, naturally occurring amino acid) or of a peptide contain omissions, and changes may bemade without departing ing 2 to 20 amino acid segments, especially an enkepha 25 from the spirit thereof. Accordingly, it is intended that lin, endorphin or LHRH analogue. Specific preferred the scope of the present invention be limited solely by compounds of subclass (B) are those wherein D is a the scope of the following claims. protected residue of a natural amino acid, such as tryp What is claimed is: tophan or tyrosine, or other amino acid/neurotransmit 1. A compound having the formula ter such as GABA, y-vinyl GABA or y-acetylenic 30 GABA; an antibiotic, e.g. a penicillin-type antibiotic, such as amplicillin, 6-aminopenicillanic acid or amoxicil lin, or a cephalosporin-type antibiotic, such as cepha lexin, ceforanide or cefroxadine; an anticancer/antitu mor agent, e.g. a nitrogen mustard type such as melpha 35 lan, a urea type such as DON, or other anticancer/an titumor agent such as acivicin or L-alanosine: a peptide such as met-enkephalin, leu-enkephalin, y-endorphin, a-endorphin, 6-endorphin, or an endorphin, enkephalin or a non-toxic pharmaceutically acceptable salt thereof, or LHRH analogue containing a COOH group and a 40 wherein each -OR is independently -OH or -OY primary, secondary or tertiary amino group; a hypoten wherein Y is a hydrolytically or metabolically cleavable sive, e.g. methyldopa; or a sympathetic stimulant, e.g. hydroxyl protective group; R is H, -COOH or levodopa. -COOY" wherein Y" is a hydrolytically or metaboli (C) Compounds of formulas (I) and (II) wherein the cally cleavable carboxyl protective group; and centrally acting amine from which D can be considered 45 to be derived also contains at least one -OH functional group, and D in formula (I) or (II) contains, in place of at least one of the -OH functional groups in said amine, -C) at least one-OY group wherein Y is a hydrolytically or metabolically cleavable hydroxyl protective group. Within subclass (C), preferred compounds are those is a radical of the formula wherein Y is an acyl group or a carbonate group and/or wherein D is the residue of a neurotransmitter,espe cially a catecholamine, or LHRH or an analogue thereof. At the present time, preferred compounds in 55 this general class include those in which D is a pro tected residue of a neurotransmitter, especially a cate cholamine such as dopamine, epinephrine or norepi nephrine, or other neurotransmitter such as serotonin; of a structurally related compound such as phenyleph rine or tyramine; or of LHRH or an LHRH analogue containing a tyrosine, serine or threonine amino acid residue (i.e., an OH-containing portion) and a primary, secondary or tertiary amino group. (D) Compounds of formulas (I) and (II) wherein the 65 centrally acting amine from which D can be considered to be derived also contains at least one -OH functional group and at least one -COOH functional group, and 5,082,853 149 150 wherein the dotted line in formula (a) indicates the cally cleavable carboxyl protective group; the dotted presence of a double bond in either the 4 or 5 position of line indicates the presence of a double bond in either the the dihydropyridine ring; the dotted line in formula (b) 4 or 5 position of the dihydropyridine ring; and R is indicates the presence of a double bond in either the 2 or halo, C1-C7 alkyl, C1-C7 alkoxy, C2-C8 alkoxycar 3 position of the dihydroquinoline ring system; miszero 5 bonyl, C2-C8 alkanoyloxy, C1-C7 haloalkyl, C1-C7 al or one; n is zero, one or two; p is zero, one or two, kylthio, C1-C alkylsulfinyl, C1-C, alkylsulfonyl, provided that when p is one or two, each Rin formula -CH=NOR" wherein R"is H or C1-C, alkyl, and (b) can be located on either of the two fused rings; q is -CNR'R' wherein R' and R', which can be the same zero, one or two, provided that when q is one or two, or different, are each H or C-C alkyl. each Rin formula (c) can be located on either of the two O 6. A compound according to claim 5 having the for fused rings; and each R is independently selected from mula the group consisting of halo, C1-C7 alkyl, C1-C7 alkoxy, C2-Cs alkoxycarbonyl, C2-Cs alkanoyloxy, C1-C7 halo alkyl, C1-C7 alkylthio, C1-C7 alkylsulfinyl, C1-C alkyl sulfonyl, -CH=NOR" wherein R"is H or C1-C, 15 alkyl, and -CNR'R' wherein R' and R", which can be the same or different, are each H or C1-C alkyl. 2. A compound according to claim 1, wherein n, m, p or q is one, and wherein R is located in the 3 position of the dihydropyridine ring, in the 3 position of the dihy- 20 droquinoline ring system or in the 4 position of the dihydroisoquinoline ring system. w or a non-toxic pharmaceutically acceptable salt thereof, 3. A compound according to claim 2, wherein R is wherein each -OR is independently -OH or -OY -CONH2. wherein Y is a hydrolytically or metabolically cleavable 4. A compound according to claim 1 having the for 25 hydroxyl protective group; R is H, -COOH or mula -COOY" wherein Y" is a hydrolytically or metaboli cally cleavable carboxyl protective group; the dotted line indicates the presence of a double bond in either the 4 or 5 position of the dihydropyridine ring; and R is RO 30 halo, methyl, ethyl, methoxy, ethoxy, ethoxycarbonyl, isopropoxycarbonyl, acetoxy, pivalyloxy, isobutyry loxy, C1-C2 haloalkyl bearing 1 to 3 halogen substitu RO ents, methylthio, methylsulfinyl, methylsulfonyl, -CH =NOH, -CONH2 or -CONCH3)2. 35 7. A compound according to claim 5 having the for (R) mula or a non-toxic pharmaceutically acceptable salt thereof, wherein each -OR is independently -OH or -OY wherein Y is a hydrolytically or metabolically cleavable hydroxyl protective group; R is H, -COOH or -COOY" wherein Y" is a hydrolytically or metaboli cally cleavable carboxyl protective group; the dotted line indicates the presence of a double bond in either the 4 or 5 position of the dihydropyridine ring; n is zero, one or two; and each R is independently selected from 45 the group consisting of halo, C1-C7 alkyl, C1-C7 alkoxy, or a non-toxic pharmaceutically acceptable salt thereof, C2-Cs alkoxycarbonyl, C2-C8 alkanoyloxy, C1-C7 halo wherein each -OR is independently -OH or -OY alkyl, C1-C alkylthio, C1-C7 alkylsulfinyl, C1-C alkyl wherein Y is a hydrolytically or metabolically cleavable sulfonyl, -CH=NOR" wherein R"is H or C1-C, hydroxyl protective group; R is H, -COOH or alkyl, and -CNR'R' wherein R' and R", which can be -COOY" wherein Y" is a hydrolytically or metaboli the same or different, are each H or C-C7 alkyl. cally cleavable carboxyl protective group; the dotted 5. A compound according to claim 4 having the for line indicates the presence of a double bond in either the mula 4 or 5 position of the dihydropyridine ring; and -CONR'R' is -CONH2 or -CONCH3)2. 55 8. A compound according to claim 7 having the for mula

CH2CHR, N or a non-toxic pharmaceutically acceptable salt thereof, wherein each -OR is independently -OH or -OY 65 Ol. wherein Y is a hydrolytically or metabolically cleavable hydroxyl protective group; R is H, -COOH or or a non-toxic pharmaceutically acceptable salt thereof, -COOY wherein Y" is a hydrolytically or metaboli wherein each -OR is independently -OH or -OY 5,082,853 151 152 wherein Y is a hydrolytically or metabolically cleavable hydroxyl protective group; R is H, -COOH or -COOY" wherein Y" is a hydrolytically or metaboli cally cleavable carboxyl protective group; and -CONR'R' is -CONH2 or -CONCH3)2. 9. A compound according to claim 8 having the for mula (R) (R) (a) (b) 10 N CH2CHR, or RO N (R) Ol. 15 (c) wherein n is zero, one or two; p is zero, one or two, provided that when p is one or two, each Rin formula or a non-toxic pharmaceutically acceptable salt thereof, (b) can be located on either of the two fused rings; q is wherein each -OR is independently -OH or -OY 20 zero, one or two, provided that when q is one or two, wherein Y is a hydrolytically or metabolically cleavable each Rin formula (c) can be located on either of the two fused rings; and each R is independently selected from hydroxyl protective group; R is H, -COOH or the group consisting of halo, C1-C7 alkyl, C1-C7 alkoxy, -COOY", wherein Y" is a hydrolytically or metaboli C2-C8 alkoxycarbonyl, C2-C8 alkanoyloxy, C1-Chalo cally cleavable carboxyl protective group. alkyl, C1-C alkylthio, C1-C alkylsulfinyl, C1-C alkyl 10. A compound according to claim 1, wherein Rhis 25 sulfonyl, -CH=NOR" wherein R"is H or C-C, H. alkyl, and -CNR'R' wherein R and R", which can be the same or different, are each H or C1-C alkyl. 11. A compound according to claim 9, wherein Rhis 8. A quaternary salt according to claim 17, having H. te 12. A compound according to claim 10, wherein each -OR is -OY wherein Y is a hydrolytically or meta 30 bolically cleavable hydroxyl protective group. 13. A compound according to claim 11, wherein each CHHR, -OR is -OY wherein Y is a hydrolytically or meta N-- X bolically cleavable hydroxyl protective group. 35 14. A compound according to claim 12, wherein Y is alkanoyl having 2 to 8 carbon atoms. (9. - 15. A compound according to claim 13, wherein Y is wherein -ORa, Rb and X are as defined in claim 17. alkanoyl having 2 to 8 carbon atoms. R 19. f quaternary salt according to claim 18, wherein 16. The compound according to claim 15, which is b. 1S i. 1-(3,4-dipivaloyloxy)phenethyl-3-carbamoyl -1,4-dihy 20. A quaternary salt according to claim 19, wherein each -OR is -OY wherein Y is a hydrolytically or dropyridine. metabolically cleavable hydroxyl protective group. 17. A non-toxic pharmaceutically acceptable quater 21. The quaternary salt according to claim 20, which nary salt having the formula is 1-(3,4-dipivaloyloxy)phenethyl-3-carbamoyl 45 pyridinium trifluoroacetate or 1-(3,4-dipivaloyloxy) phenethyl-3-carbamoylpyridinium chloride. 22. A pharmaceutical composition of matter compris E. amount of a compound as claimed in claim 1 sufficient to evoke an effective dopaminergic response and a non-toxic pharmaceutically acceptable carrier therefor. 23. A pharmaceutical composition of matter compris ing an amount of a compound as claimed in claim 10 sufficient to evoke an effective dopaminergic response and a non-toxic pharmaceutically acceptable carrier wherein each -OR is independently -OH or -OY 55 therefor. wherein Y is a hydrolytically or metabolically cleavable 24. A pharmaceutical composition of matter compris hydroxyl protective group; R is H, -COOH or ing an amount of a compound as claimed in claim 13 sufficient to evoke an effective dopaminergic response -COOY" wherein Y" is a hydrolytically or metaboli and a non-toxic pharmaceutically acceptable carrier cally cleavable carboxyl protective group; X is the therefor. anion of a non-toxic pharmaceutically acceptable acid; 60 25. A pharmaceutical composition of matter accord and ing to claim 17, said composition being formulated as a pharmaceutically acceptable sustained release composi tion. 26. A method for treating Parkinsonism or hyper prolactinemia in an animal in need of such treatment, -N) 65 said method comprising administering to said animal an effective anti-Parkinsonism or anti-hyperprolactinemia amount of a compound as claimed in claim 1. is a radical of the formula is