Jan 0 5 1.995 Chemistry 1
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1 R ECEt abr~ FINAL TECHNICAL PROGRESS REPORT JAN 0 5 1.995 CHEMISTRY 1. SYNTHESIS AND 8ECEPTOR AFFINITIES OF NEW 3-QUINUCLIDINYL ALPHA- HETEROARYL-ALPHA-ARYL-ALPHA-HYDROXYACETATES (see Schemes in App. 1.1). Five analogues of 3-quinuclidinyl benzilate were prepared in which one phenyl ring was substituted by a heterocycle; a bromine was included on either the remaining phenyl or the heterocycle to provide information relating to the affinity of potential radiohalogenated derivatives. The required methyl 4- bromophenylglyoxalate ( 1 ) was synthesized from the reaction between 4-bromophenylmagnesium bromide with an excess of dimethyl oxalate at -700 C. The reaction between ethyl oxalyl chloride with 2-bromothiphene provides ethyl 2-(5-bromothienyl)glyoxatate (2). Compounds ( 1) and (2) react with an equivalent amount of Grignard reagent to provide methyl or ethyl alpha-aryl-alpha- heteroarylglycolates (3). Transesterification of the methyl or ethyl esters (3) with (R,S)-3- quinuclidinol (4) in the presence of sodium metal provides the final products As a result of screening the novel compounds, we found a heterocyclic derivative of QNB that may(5). surpass IQNB as a CNS receptor radioligand. This novel compound binds to mAChRs with an affinity that is greater than that of IQNB, i5 selective for the ml subtype, and is less lipophilic than IQNB, which should reduce the serum proteip binding relative to IQNB. Cohen, Gibson, Fan, De La Cruz, Gitler, Hariman, Reba J. Pharm. Sci., 8'1, 326-329, 1992; App. 1.l. 2. SYNTHESIS AND STRUCTURE-ACTIVITY RELATIONSHIP OF SOME 5- [ [ [ ( D IA LKY LA M I N 0)ALKYL]- 1 -PIPE RI D I NY L] ACETYL] - 1 0,l 1 -D IHY D RO-5 H-D IB EN20 [ b, e] [ 1,4] DIAZEPIN- 1 1-ONES AS rn2-SELECTIVE ANTlMUSCARlNlCS (see Schemes in App. 1.2). The required 1 1-oxo-1 0,l 1-dihydro-5H-dibenzo[b,e] [1,4]diazepine (9) was prepared from the reaction between 2-chlorobenzoic acid and o-phenylenediamine. The reaction between 2- and 4- vinylpyridines (5a,b) and dialkylamines (6a-e) provided 2- and 4-(dialkylamino)ethylpyridines (7). 4-Picolyllithium '(5~)reacted with 3-(dimethyl- or diethy1amino)propyl chloride to provide 4-[4-( dimethyl- or diethylamino) butyllpyridines (7). [(Dialkylamino)alkyl]pyridines -(7) were converted into the respective piperidines (8) by catalytic reduction(p1atinum oxide). Condensation of the tricycle (9) with chlocoacetyl chloride provided 5-(chloroacety1)-1 0,l 1-dihydro-SH- dibenzo[b,e][1,4] diazepin-1 l-one ( 1 0). Subsequent reaction with [(dialkylamino)alkyl]piperidines (8) yielded the final products (4)- Compounds (4a-g,iIj) and two reference compounds (Table 111 in App. 1.2) were tested for their apparent affinities for the ml and m2 subtypes. Table 111 compares the selectivity and potency of these compounds to other compounds. These data demonstrate that (4j) is the most potent compound in the series. This compound is selective for m2 receptors over ml receptors by approximately 8-fold. These results also demonstrate that (41) is approxhately 10 times more potent at m2 receptors than AQ-RA 741. However, (4j) does not significantly penetrate the BBB. Cohen, Baumgold, Jin, de la Cruz, Rzeszotarski, Reba, J. Med. Chem. 36, 162-1 65, 1993a; App.. 1.2. .- 3. SY~THESIS OF SOME DIBENZODIAZEPINONES AS - POTENT m2-SELECTIVE ANTlMUSCARlNlC COMPOUNDS (see Schemes in App. 1.3). 4-[4-(Chloro)butyl]cyclohexylacetic acid (4) was obtained by catalytic reduction of 4-[4-(chloro) butyl]phenylacetic acid (3). Reaction of acid derivatives (4, 5) with thionyl chloride, followed by condensation with tricycle (S), and then reaction with secondary amines provided the final products (1, 2). To increase the lipophilicity in this series, we replaced the piperidine ring in the cationic head by cyclohexyl ring (Table I in App. 1.3). Compounds (1 a-h), and (2a,b) and three reference compounds were tested for their apparent affinities for ml and m2 subtypes. The ICgo's for the muscarinic ligands were determined by competitive ligand binding assay against [3H]QNB. These data demonstrate that (2b) is the most potent compound in the series. The data (Table 111 in App. 1.3.) reveal that neither preinjection nor coinjection of the m2-selective compound (2b) at a dose of 500 nmol or 2000 nmol affects the re ional (R,R)-[1251]lQNB accumulation in the rat brain. There was no displacement of (R,R)- [1%%JIQNBfrom specific brain regions by the unlabeled compound (2b). Cohen, Jin, Gitler, de la Cruz, Rzeszotarski, Zeeberg, Baumgold, Reba; J. Heterocyclic Chem. in press; App. 1.3. DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED 9b ~~~~~~~ 4. 1 We have Synthesized 1,s- benzodiazepinesTHE SYNTHESIS (Scheme OF1.h SUBSTITUTEDApp. 1.4). where ,S-BENZODIAZEPINES.crotonic acid (1)'or methacrilic acid (2) react with 1,2-~henylenediamine (Sa) or 4-chloro-l,2-phenylenediamine (3 b) leading to tetrahydro-2H- 1,5-benzodiazepihe-2-ones (4),, Condensation of (4) with bromoacetyl chloride followed by 2- diethy laminoethyl-piperidine ;( 6), 4-dimethylaminobutyl-piperidine (7), or diethylaminobutyl- piperidine (8) afforded substituted 1,s-benzodiazepines (9). The reduction in size of the tricycle resulted in a loss of affinity. Cohen, Jin, Reba, J.Heterocyclic Chem. 30, 835-837, 1993; App. 1.4. 5. NOVEL POTENT AND M2-SELECTIVE ANTIMUSCARINIC COMPOUNDS WHICH PENETRATE THE BLOOD BRAIN BARRIER. These compounds (1 a-n) were prepared according to the Scheme in App. 1.5. The 4-(methoxyalkyl)phenylacetonitriles were converted to 4- (bromoalkyl) phenylacetic acids (Sa-d) by hydrolysis, cleavage, and halogenation. Subsequent reaction of (Sa-d) with thionyl chloride, followed by condesation with 1 1-oxo-1 0,ll -dihydro-SH- dibenzo[b,e] [ 1,4]diazepin (6) yielded the 5-[[4-(haloalkyl)-l -phenyl]acetyl]-1 0,ll -dihydro- SH-dibenzo[b,e][l,4]diazepin-l1 -ones (7a-d). The reaction of (7a-d) with secondary aliphatic amines provided (1 a-n). Further synthetic details are described in the enclosed manuscript. Compounds (la-n) and three reference compounds (Table V in App. 1.5) were tested for their apparent affinities for the ml and m2 subtypes. The results demonstrate that (1 h) (DIBD) is the most potent compound in the series. DIBD is selective for m2 receptors over ml receptors by approximately 7-fold. These results also demonstrate that DlBD is approximately 10 times more potent at m2 .: receptors than is AQ-RA 741. Cohen, Jin, Gitler, de la Cruz, Boulay, Zeeberg, Reba, submitted to Eur. J. Med. Chem.; App. 1.5. 6. FACILE AND GENERAL SYNTHESIS OF 2-, 30, OR 4-[(DIALKYLAMINO) ALKYLIPYRIDINES AND PIPERIDINES. Reaction of N,N-dialkyiaminoalkyl chloride with picolyllithiurns ( 1 ) provided the pyridine derivative from which the piperidine (3) was synthesized by catalytic hydrogenation. Cohen, Jin, Reba, Liebigs(2) Ann. Chem. pp. 809-81 0, 1993. H 1 2 3 7. SYNTHESIS OF 20. AND 4-IODO-5-[[4-[4-(DIISOBUTYLAMlNO)BUTYL]-l- PHENYLIACETYLFl0,l l-DIHYDRO~5H-DiBENZO[b,e] [ 1,4]DIAZEPIN-ll-ONES ( 1 0a, b ) ;/( S C H E M E) : 2 - I 0 D 0- 5 - [ [ 4-.[ 4 - ( D I I S 0B U T Y LA M I N 0) 6 U T Y L ]- 1- P H E N Y L ]- ACETYL]-1 0,l 1-DIHYDRO-5H-DIBENZO[b,e][ 1,,4]DIAZEPIN-l1-ONE (24DIBD, 1 Oa). It was synthesized according to Scheme. o-Phenylenediamine was condensed with 2-chloro-5- nitrobenzoic acid as described by Giani (1985), to give 2-nitro-1 1-oxo-1 0,ll -dihydro-5H- dibenzo[b,e][ 1,4]diazepine (1a). 2-Nitro-1 1-oxo-1 0,ll -dihydro-5H-dibenzo[b,e]- [1,4]diazepine (1 a) was converted into the 2-mino-1 1-oxo-1 0,l 1-dihydro-SH- dibenzo[ b,e] [ 1,4]diazepine (2a) by catalytic-reduction (palladium on activated carbon). Reaction of (2a) with benzylchloroformate (3) by a modification of Holley (1 954) provided 2- benzyloxycarbonyl(Z)amino-1 1-oxo1 0,ll -dihydro-SH-dibenzo[b,e][ 1,4]diazepine (4a). The 2- benzyloxyca r bony1(Z) a mi no-5-[ [4- [4-( bromo) butyl]- 1-p heny I]acetyl] - 1 0,ll -di hydro- 5 H-di- benzo[b,e] [1,4]diazepin-l1 -one (sa) was prepared by treating (4a) with 4-[4-( bromo)butyl]- phenylacetyl chloride (5). The desired 2-benzyioxycarbonyl(Z)amino-5-[ [4-[4- (diisobutylamino) butyl]-1 -phenyl]acetyl]-1 0,ll -dihydro-SH-dibenzo[b,e][ 1,4]diazepin-l1 -one (8a) was synthesized from reaction of the (6a) with diisobutylamine (7) in acetonitrile by the method described by Cohen (App. 1S). Compound (8a) was hydrogenated at room temperature in the presence of palladium on active carbon according to Fletcher (1 979) to give the respective amine (ga). The 2-iodo-5-[[4-[4-(diisobutylamino)butyl]-l -phenyl]acetyl] 10,l 1-dihydro-SH- dibenzo[b,e][ 1,4] diazepine-11-one (1Oa) was synthesized from reaction of the diazonium intermediate with potassium iodide by the method described by Cohen (1 989). The residue was purified by flash column chromatography elution with chloroform/methanol 10: 1); mp = 137%. in vitro competition binding studies against [f HlQN6 provided the following IC50 values. Thus, iodination in the 2-position significantly reduces the binding affinity of DIBD, whereas iodination in the 4- position retain the aff inity, but reduces the subtype specificity. 1 2 4 6 8 9 10 - - compound ml m2 ml/m2 DIBD 25 3.2 7.81 2-IDIBD 200 90 2.22 - 4-1~i~b 10 S 2.0 8. SY NTHES I S 0 F 5-[ [ 4-14-1 D I ( 2-M ETHY LALLY L) AMI N 01 BUTYL] - 1 -PHENYL] ACETYL]:JP, 1 1,4]DIAZEPIN-l 1 -ONE [unsaturated precursor for preparingl-DIHYDRO-SH-DiBENZO[b~e][ tritiated DlBD (UDIBD)] The best m2-selective antimuscarinic agent studied in the above (section S) series of compound is 5-[[4-[4-(diisobutylarnino)butyl]-l- phenyllacetyll-10,ll -dihydro-SH-dibenzo[b,e] [ 1,4]diazepin-11 -one (DIBD), which penetrates the blood brain barrier and displays in vivo selectivity for the m2-subtype.