2-ISOPROPYL-3-(P-AMINO-PHENYL)-3H-4-QUINAZOLONE

1,148,074. 2 - Alkyl - 3 - aminophenyl - 3H - 4-quinazolones. BOEHRINGER INGELHEIM G.m.b.H. 2 May, 1966 [5 May, 1965], No. 19300/66. Heading C2C. The invention comprises 2-isopropyl-3-(41- amino - phenyl) - 3H - 4 - quinazolone and 2 - decyl - 3 - (21- methyl - 41 - amino - phenyl) - 3H - 4 - quinazolone, of the formula wherein either R 1 is isopropyl and R 2 a hydrogen atom or R 1 is a decyl group and R 2 a methyl group, and their acid addition salts. The novel compounds may be made reacting the corresponding nitro compound with a reagent serving to reduce a nitro group to an amino group, preferably by catalystic hydrogenation or by use of nascent hydrogen. Alternatively the compound in which R 1 is an isopropyl group and R 2 is a hydrogen atom may be made by condensing N-isobutyryl anthranilic acid with p-phenylene diamine. The pharmacological properties of these compounds and others in which R 1 is CH 3 , C 2 H 5 , C 3 H 7 , C 4 H 9 , i-C 4 H 9 , C 5 H 11 , C 6 H 13 , C 7 H 15 , C 8 H 17 , C 9 H 19 , C 10 H 21 , C 11 H 23 , C 13 H 27 , C 15 H 31 , or C 17 H 35 , are listed demonstrating that only the compounds of the invention have sedative action without side effects such as inducing cramp. 2 - Isopropyl - 3 - (41- nitrophenyl) - 3H - 4 - quinazolone is obtained from N - isobutyrylanthranilic acid and p-nitroaniline in the presence of a dehydrating agent, e.g. POCl 3 or PCl 3 . 2 - n - Decyl - 3 - (21 - methyl - 41- nitro - phenyl) - 3H - 4 - quinazolone is similarly obtained from N-undecanoyl-anthranilic acid and 5-nitro-2-aminotoluene. N - isobutyryl - anthranilic acid is obtained from anthranilic acid and isobutyric acid chloride or anhydride, or by oxidation of N - isobutyryl - o - toluidine with KMnO 4 . N - Undecanoyl - anthranilic acid is similarly obtained. Pharmaceutical compositions, having marked stimulation on the central nervous system and only moderate sedative action, comprise at least one of the compounds of the above formula in association with a pharmaceutical carrier or excipient, preferably in forms suitable for oral administration.