2,872,370 United States Patent 0 1C6, .- Patented Feb. 3, 1959

1. 2 4 parts of acetophenetldin, I prefer to use three parts of 2,872,370 to about one part of acetophenetidin. HY PN OTIC vCOMPOSITION CONTAINING ABOUT A series of experiments were carried out on various 1 TO 3 PARTS ACETOPHENETIDIN AND ABOUT animals including mice, rats, rabbits, and cats, but the 3 T0 1 PARTS SALICYLAMIDE results listed in the following tables were obtained on mice. In these experiments the compositions were in Frank‘M. Berger, Princeton, N. J., assignor to Carter jected by the introperitoneal route. This route of admin Products, Inc., New York, N. Y., a corporation of Maryland istration has been used because in this way absorption occurred rapidly and the results were more uniform. No Drawing. Application July 22, 1953 Mice were used because with these animals a large num Serial No. 369,718 ber can be more easily accommodated than is the case with larger laboratory animals, and the performance of 2 Claims. (Cl. 167-52) tests on a larger number of animals gives more reliable This invention relates to hypnotic or sleep-producing results. It has,‘however, been shown that the composi drugs and has for its object the provision of an effective 5 tions are also effective if given by mouth, enema, or by composition for this purpose consisting of commonly intramuscular or intravenous injection. used drugs. The essential and effective active Because the presence or absence of light sleep does components of ,the composition are acetophenetidin not lend itself to objective evaluation, it is preferred to (, p-ethoxy ), and one of the com use the presence of very deep sleep when establishing the pounds of the group consisting of salicylamide and‘ efficiency of the compositions. During very deep sleep, benzamide. Acetophenetidin and salicylamide are fre the animals will tolerate a dorsal position and will remain quently employed alone or in admixture with other active . in this position as long as the effect of the composition materials in the treatment of minor rheumatic pains and lasts. They will spontaneously turn over to their nor aches, headaches and toothaches, but have no sleep mal position on awakening. The duration of sleep was producing properties when used alone or in such mixtures‘. taken as the time commencing with the moment at which My invention is based on my discovery that suitable the animals tolerated being put on their backs and ending proportions of these commonly used analgesic drugs pro with’their turning over to the normal posture. duce deep. sleep without causing untoward side effects. All animals were injected with graded doses of the While I prefer to form the composition of acetophenetidin various compositions, the doses increasing on a log and salicylamide, I may use benzamide in place of salicyl arithmic scale by a factor of 1.5. All animals were in amide although it is not fully as effective. A preferred jected according to their body weights. After injection of composition of my invention consists essentially of aceto any of the substances mentioned in doses given in the phenetidin and salicylamide in such proportions by weight tables, no neurological de?cits were observed and the that they complement each other in convenient doserquan animals remained normal in every respect. When higher tities, in producing sound sleep for several hours. doses than those given in the tables were injected, some In the course of my extensive investigations I have neurological impairment such as ataxia or reduction of made the surprising discovery that these common drugs spontaneous movement was observed in some cases. produce an effect in combination that they are incapable Table I which follows gives the effects of various doses of salicylamide and acetophenetidin and mixtures there of producing alone. The ‘following compounds, which 40 are somewhat related to acetophenetidin, when admixed of. Doses of 280 mg./kg. of salicylamide and 420 with salicylamide as a substitute for acetophenetidin, rug/kg. of acetophenetidin, each taken alone, did not produced varying degrees of sleep in animals: acetanilide produce any symptoms. The table shows the results of (antifebran, N-phenyl acetamide), aminopyrine (amido using various proportions of the two drugs. pyrine, 4-dimethylamino-1,5-dimethyl-2-phenyl-3~pyrazo 45 lone), phenetsal (Salophen, ester of para Table I acetylamiuophenol), p-phenetidin (4-aminophenetole), p-aminophenol (4~amino-l-hydroxybenzene) and p-acet Amount of Amount of Salicylam- Acetophen- Percent of Duration a'minophenol (N-acetyl-p-aminophenol). ide in etldiu in Animals of Sleep When acetophenetidin is admixed with these com 50 Dose, Dose, Asleep in Minutes pounds somewhat related chemically to salicylamide, only mgJkg. max/kg benzamide has been found to be effective. Among the 280 0 0 0 compounds which are ineffective are: meta hydroxy 0 420 0 0 benzamide, para hydroxy benzamide, salicylic acid, sodi 280 420 100 154 280 280 100 119 um salicylate, acetyl-salicylic acid (), p-amino 55 280 180 100 59 , nicotinamide, phenetsal, 280 120 100 70 280 80 70 25 (Wintergreen oil), phenyl salicylate (Salol), gentisic acid 280 55 0 0 (2,5-hydroxy benzoic acid), o-hydroxybenzyl 180 420 100 67 120 420 40 31 (salicyl alcohol, Saligenin), antipyrine and aminopyrine. 80 420 0 0 The essential components of the composition must be 60 proportioned to result in a satisfactory sleep effect when given in conveniently proportioned doses of from 1 to 3 Table II which follows shows the sleep-producing ac tablets of from around 5 to 7.5 grains each. While I ‘ tion of various mixtures of acetophenetidin and salicyl may use one part of salicylamide to from 0.25 to around amide. 2,872,370

Table 11

Amount of Amount of 10 Mice Sallcylam- Acctophen- Total Treated— Induc Durationzl; ide in etldin in Dose, Number of tion S. E. Dose, Dose, mgJkg. Mice mgJkg. mgJkg. Asleep

160 480 640 10 3. 5 67. 85:5. 9 Mixture 1 ______105 315 420 1 4.1 9.2 70 210 280 0 ______210 210 420 10 4. 1 39. 3:113. 9 Mixture 2 ______-_ 180 180 360 3 4. 9 17. 53:8. 2 140 I 140 280 0 ______270 90 360 8 3. 4 56.451. 1 Mixture 3 ______210 70 280 4 6. 6 18. 8:116. 3 ' 135 45 180 0 ...... 66

The mean hypnotic doses and their standard errors are for mixture 1, 490127; for mLxture 2, 372=e10; for mixture 3, 300=b22—all in mgru. per kgm. of body weight. In mixture No. 1, one part of salicylamide was com acetophenetidin and benzamide in similar proportions to bined with three parts of acetophenetidin; in mixture No. 20 those described above produced deep sleep but for shorter 2 equal parts of both ingredients were combined; in mix durations. While I prefer to use a simple composition ture No. 3, one part of acetophenetidin was combined consisting of acetophenetidin and salicylamide, I may also with three parts of salicylamide. Graded doses of each use mixtures or blends of salicylamide and benzamidc of these mixtures were injected to groups of animals and with the acetophenetidin. the duration of sleep with each group was observed. 25 I claim: The probit of the percentage response was plotted against 1. A sleep-producing composition. substantially free of the logarithm of the dose given, and the dose e?ective in stimulating agents containing as the active ingredients 50 percent of the animals read oti the graph. This value acetophenetidin in an amount or‘ about 1 to about 3 was called the mean hypnotic dose or HD50. The stand parts by weight and salicylamide in an amount of about ard error of this dose was calculated by statistical method 30 3 to about 1 part by weight. conventionally used. This calculation was carried out 2. A sleep-producing composition according to claim for each mixture. It was found that mixture No. 1 had 1 containing about three parts by Weight of salicylamide an HD50 of 490, whereas mixture No. 3 had an HD5O of , and one part by weight of acetophenetidin. 300. Thus, mixture No. 3 is considerably more effective References Cited in the ?le of this patent than mixture No. 1 because only 300 mg. per kg. of mix 35 ture No. 3 were required to put 50 percent of the animals UNITED STATES PATENTS to sleep, whereas 490 mg. per kg. of mixture No. 1 were 2,675,340 Pilcher et al ______Apr. 13, 1954 required to obtain a similar effect. 1 The compositions of the invention are primarily in OTHER REFERENCES. tended for oral use and are preferably intermixed in a 40 Wilson et al.: Organic Chem. in Pharmacy, Lippin‘ dry pulverulent state and formed into suitable pills, tab cott, Phila., 1949, pp. 233-236, and 130. lets or capsules by well known practices. They may also Goodman et al.: Pharmacol. Basis of Then, lst ed., be dissolved in a suitable solvent such as water for injec 1941, Macmillan C0. N. Y. (3., pp. 234, 242-246. tion or for use as enemas. It will be apparent that pills Lasagna: I. of Pharmacol. and Exp. Ther., May 1954, or tablets each containing but one of the two components 45 pp. 9-20. may be formed for taking at the same time, and when Chain Store Age, Drug Executives, Ed, vol. 28, No such tablets are taken at the same time as a sleep-produc vember 1952, See. 1,13. 75. ing dose they are considered compositions of the inven Brit. M. I. I (March 14, 19553), p. A-IS (advt). tion. I Extra Pharmacopoeia, vol. 1, 23rd ed., 1952, pp. 9, 89. In similar experiments compositions consisting of Frankel: Arzneimittel:Synthese, 1927, pp. 278 and 536.