Benzophenone derivatives

Abstract

The present invention relates to pharmacologically valuable new benzophenone derivatives having a pronounced sedative action on the central nervous system and some of which also possess muscle-relaxing and aggression-inhibiting properties. These new derivatives have the structural formula ##STR1## and the pharmaceutically-acceptable acid-addition salts thereof in which R.sub.1 and R.sub.2 are substituents selected from the group consisting of hydrogen, saturated and unsaturated alkyl groups having 1-4 carbon atoms; R.sub.3 is selected from the group consisting of --COOC.sub.3 H.sub.7, --COOC.sub.4 H.sub.9, --COOC.sub.6 H.sub.5, --C.sub.6 H.sub.5, ##STR2## whereby R.sub.4 is an aliphatic radical with 1 to 4 carbon atoms or phenyl and Y is an oxygen or sulfur atom; if m is O R.sub.3 is further selected from the group consisting of --COOCH.sub.3 and --COOC.sub.2 H.sub.5 ; n is an integer selected from 1 and 2; and m is an integer selected from 0, 1, 2 and 3, and wherein the rings A and B may be substituted, ring A being substituted preferably with halogen, such as chlorine, or with nitro, trifluoromethyl, methyl, methoxy or methylmercapto, preferably in the 5-position, and ring B being preferably substituted in the 2'-position with chlorine or fluorine. The radicals R.sub.1 and R.sub.2 preferably signify hydrogen or a methyl group, or a n-butyl group in the case of Ring B. Compounds represented by the above structural formula may be produced by reacting a compound represented by the formula ##STR3## with a compound having the formula Y -- C.sub.m H.sub.2m -- R.sub.3, one of X and Y signifying the substituent R.sub.2 -- NH -- and the other signifying a halogen atom, preferably a bromine or chlorine atom, so as to form the above specified benzophenone derivative with the elimination of H -- Hal; R.sub.1, R.sub.2, R.sub.3, n and m being as defined above, and the rings A and B being optionally substituted as discussed above. The hydrogen halide which is eliminated is advantageously bound by the addition of an acid-binding agent, as for example, a molar excess of the amine used in the reaction or, for example, triethylamine, dimethylaniline, potassium or sodium carbonate or sodium bicarbonate. The reaction is carried out in a suitable solvent, preferably at an elevated temperature, typically the reflux temperature of the solvent used.