GB999395A - New compounds of the yohimbane series and process for their manufacture - Google Patents

Abstract

The invention comprises compounds of the general formula <FORM:0999395/C2/1> (wherein R1 represents a hydrogen atom or an unsubstituted or substituted aliphatic hydrocarbon group, R2 represents a C1-4 alkoxy group, R3 represents a hydrogen atom or the acyl radical of an aliphatic or a monocyclic aromatic or araliphatic carboxylic or sulphonic acid, R4, R5 and R6 each represent a hydrogen or halogen atom or a C1-4 alkyl, alkoxy or alkylmercapto group or two of them in adjacent positions together represent an alkylenedioxy group of 1 or 2 carbon atoms, and R7 represents a hydrogen atom or a C1-4 alkyl group) and their N-oxides, and salts of these compounds, and the preparation thereof by hydrolysing a compound of the general formula <FORM:0999395/C2/2> (wherein R represents the acyl radical of an organic sulphonic acid) or an N-oxide thereof or a salt of either compound, and, if desired, splitting or transesterifying a resulting carboxylic acid ester, or esterifying a resulting acid with an aliphatic alcohol, and/or acylating a compound in which R3 = H with a reactive functional derivative of an aliphatic or a monocyclic aromatic or araliphatic carboxylic or sulphonic acid, and/or N-oxidizing a resulting tertiary compound or reducing a resulting N-oxide, and/or converting a resulting base into a salt thereof or a resulting salt into the corresponding base. Sulphonic esters of the second general formula above are prepared by reacting the corresponding 18B-hydroxy compounds with an organic sulphonic acid halide in the presence of a base. Ethers.-The compounds of the first general formula above wherein R3 = H may be etherified to form compounds in which R3 represents an aliphatic hydrocarbon group. Pharmaceutical and veterinary preparations comprise the compounds of the invention, which are sedatives and tranquillizers and in some cases antifibrillatory and/or antihypertensive agents, together with a pharmaceutically suitable carrier. They may be in forms suitable for enteral or parenteral administration, e.g. tablets, dragees, capsules, solutions, suspensions or emulsions, or animal feedstuffs or feedstuff additives. Salts specified include acid addition salts with ascorbic, salicylic and p-aminosalicylic acids, methionine, tryptophan, lysine and arginine, and salts of the compounds in which R1 = H with lithium, magnesium and organic bases. Specifications 999,391, 999,392, 999,393, 999,396, 999,397, 999,398 and 999,399 are referred to