GB907820A - Octahydro-isoquinoline derivatives and the manufacture thereof - Google Patents

The invention comprises compounds of general formula <FORM:0907820/IV (b)/1> and their acid addition salts, and their precursors of general formulae <FORM:0907820/IV (b)/2> wherein R1 represents hydrogen or an alkyl radical, R2 represents halogen or a trifluoromethyl or nitro group, n is 1-3, and the broken line indicates an optional substituent; and the preparation of compounds of the first formula from the third by N-methylation, followed by nitration when R2 is absent, and then optional resolution into optical isomers. N-unsubstituted octahydroisoquinolines of the third general formula above are prepared by condensing b -[cyclohexen-(1)-yl]-ethylamine with an acid of general formula, <FORM:0907820/IV (b)/3> cyclizing the resulting amide, and reducing the resulting 1-substituted-3,4,5,6,7,8-hexahydro-isoquinoline. 4-Fluoro- and 3-trifluoromethyl-phenylpropionic acid are prepared from the corresponding benzaldehydes by condensation with malonic acid followed by decarboxylation and hydrogenation. d -(4-Nitrophenyl)-valeric acid and 4-nitrobenzyl-methyl-acetic acid are prepared by nitration of the corresponding acids free from nitro groups. Pharmaceutical compositions comprise compounds of the first general formula above and their acid addition salts together with a compatible pharmaceutical carrier. Solid (tablets, dragees, capsules, suppositories) and liquid (solutions, emulsions, suspensions) forms for oral, parenteral and rectal administration are mentioned. The compounds are analgesic and spasmolytic.