Tricyclic psychotropic agents containing two chalcogen atoms in the central ring: Synthesis of 6-(aminoalkyl) derivatives of 6H-dibenz[b,e]-1,4-oxathiepin

Abstract

Heating of 2-(2-hydroxyphenylthio)benzoic acid (XX) with acetic anhydride gave dibenz[b,e]-1,4-oxathiepin-6-one (XXII). Demethylation of 2-(2-methoxyphenylthio)benzyl bromide (XI) with boron tribromide and the following treatment with aqueous sodium hydroxide in dimethyl sulfoxide afforded 6H-dibenz[b,e]-1,4-oxathiepin (I) which was halogenated with chlorine or N-bromosuccinimide only to the undesirable 2-halogeno derivatives II and III. A reaction of 2-(2-methoxyphenylthio)benzaldehyde (XII) with chloroform and 50% aqueous sodium hydroxide in the presence of triethylbenzylammonium chloride led to the α-chloro acid XIX whose demethylation with boron tribromide and the following cyclization with sodium hydroxide in dimethyl sulfoxide gave a mixture with prevailing 6H-dibenz[b,e]-1,4-oxathiepin-6-carboxylic acid (IV). Amino alcohols XXV-XXVIII were obtained by reactions of 2-(2-fluorophenylthio)benzaldehyde (XXIV) with the corresponding Grignard reagents and the products were cyclized with sodium hydride in dimethylformamide to the title compounds V-VIII. While compounds V and VI showed antireserpine effects and can be considered as potential antidepresants, compound VIII has a strong central depressant activity, brings about ataxia, hypothermia and potentiates the cataleptic action of neuroleptics (properties of a tranquillizer).