Patent GB-545601-A (GB)
Title: Improvements in or relating to the production of í¸-5-7 sterol compounds
IPC: C07J9/00
Filed: 1940-07-06
Abstract: 545,601. Doubly unsaturated sterol compounds. DU PONT DE NEMOURS & CO., E. I. July 6, 1940, No. 11346. Convention date, July 7, 1939. [Class 2 (iii)] Doubly unsaturated sterol compounds are prepared by treating a sterol compound having a double bond adjacent to an esterified 7- hydroxy group with a compound which will form oxonium salts. Compounds mentioned for this purpose include ethers, alcohols, ketones, aldehydes, and esters. The oxonium salt forming compounds may be aliphatic, cycloaliphatic, aromatic, heterocyclic, or mixed compounds of the above types. The compound used should be such that it does not destroy # <SP>5-7</SP> sterol compounds, and a test is described using ergosterol by which all suitable compounds may be recognized. The preferred compounds are the normally liquid aliphatic and cyclic ethers, esters and ketones, and of these dioxane and acetone give the highest yields. A long list of suitable compounds is included. Compounds which have other groups in addition to the oxonium saltforming group may also be used. The presence of acid binding groups such as amino groups in addition to oxygen give satisfactory results. Compounds mentioned include morpholine, phenoxazines, the general group of acid amides and their substitution products such as stearic acid amide, acetanilide, urea, the class of alcohol amines such as ethanol-amine, keto amines such as amino-benzophenone, and ester amines such as amino acid esters. The reaction is preferably conducted in the presence of one or more reaction assisting agents. These may comprise inorganic salts having a pH value in water of 4-12 and nitrogen containing bases. An extensive list of suitable compounds and mixtures of compounds is included. In examples (1) 7-Hydroxy-cholesteryl-dibenzoate is treated with dioxane to give 7-Dehydrocholesteryl-benzoate ; (2) as in example 1 using a mixture of dioxane and piperidine ; (3) as above using morpholine ; (4) as above using dioxane with a concentrated solution of ammonia ; (5) as above using dioxane and aluminium oxide; (6) as above using a mixture of dioxane and 1/5-normal sodium chloride aqueous solution ; (7) as above using dioxane and an equimolecular part of concentrated aqueous solution of sodium phosphate. Suitable esters of the 7-hydroxy sterol compounds include those prepared from acids such as nitrobenzoic, m-dinitrobenzoic, chlorobenzoic, toluic, phenylacetic, cinnamic, formic, propionic, butyric and valeric acids, also acid anhydrides and acid chlorides. The Specification as open to inspection under Sect. 91 refers generally to the treatment of steroids having a double bond in a position adjacent to the esterified hydroxy group in the 7-position. Starting materials included are any compounds having a cyclo-pentanopolyhydrophenanthrene ring structure, and there are also referred to bile acids, heart poisons, saponines and sex hormones. Compounds specifically mentioned include 3 : 7-dihydroxy-5- cholenic acid esters, # <SP>5</SP>-androstentriol-3 : 7 : 17- triester, and the corresponding esters of the pregnane series. This subject-matter does not appear in the Specification as accepted.