GB765853A - Improvements in or relating to substituted piperidines - Google Patents

Abstract

The invention comprises vinylpiperidine compounds of the general formula <FORM:0765853/IV(b)/1> (wherein Q is phenyl, Q1 is phenyl or pyridyl and R2 is hydrogen or an alkyl group of 1-6 carbon atoms) and their acid addition and quaternary ammonium salts, and the manufacture thereof by dehydrating a carbinol of the general formula: <FORM:0765853/IV(b)/2> (wherein one of R and R1 is hydrogen and the other a hydroxy group), followed, if desired and necessary, by reductive alkylation of the product, and further, if desired, by conversion of the product into an acid addition or quaternary ammonium salt thereof. In examples: (1)-(3) diphenyl 4-, 3- and 2-pipecolyl carbinols are heated with 85 per cent sulphuric acid to produce 4 -, 3 - and 2 - (b : b - diphenyl)-vinylpiperidine, isolated in the form of their hydrochlorides; (4) diphenyl 1-methyl-2-pipecolyl carbinol oxalate similarly yields 2-(b : b -diphenyl) - vinyl - 1 - methylpiperidine hydrochloride; (5) a -(2-pyridyl)-benzyl 1-methyl-4-piperidyl carbinol similarly gives 4-[b -(2-pyridyl)-b - phenyl] - vinyl - 1 - methylpiperidine hydrochloride; (6) the product of (1) is warmed with formalin and formic acid, followed by treatment with caustic potash to liberate 4-(b : b - diphenyl) - vinyl - 1 - methylpiperidine; (7) the product of (6) is quaternated with methyl bromide; (8) the product of (3) is methylated as in (6) to form the same product as in (4); (9) and (10) the product of (4) or (8) is quaternated with methyl bromide and with methyl iodide. The products, especially in the form of salts (e.g. sulphates, phosphate, hydrochlorides, levulinates, mucates, acetates and tartrates) are useful as antispasmodic agents. Additional quaternizing reagents specified are ethyl chloride, methyl sulphate, methyl p-toluenesulphonate and benzyl bromide. Specification 765,854 is referred to.ALSO:Therapeutic preparations for the relief of smooth-muscle spasms contain vinylpiperidine compounds of the general formula:- <FORM:0765853/VI/1> (wherein Q is phenyl, Q1 is phenyl or pyridyl and R2 is hydrogen or an alkyl group of 1-6 carbon atoms) or an acid addition or quaternary ammonium salt thereof. These compounds may be employed in the form of an aqueous solution of a water-soluble salt (e.g. of sulphuric, phosphoric, hydrochloric, leonlinic, mucic, acetic or tartaric acid) or incorporated in a tablet or capsule base. The free bases or their sparingly soluble salts may be administered when a slow and prolonged effect is desired. The quaternary ammonium salts (e.g. methobromides and methiodides) have a particularly powerful action. Specification 765,854 is referred to.