HCID 53907651, compound → HCID 10863877, compound

Participants

Reaction Steps

To a solution of 8.8 g of 1α,3β-diacetyloxychola-5,16-dien-24-oic acid methyl ester in 200 ml of absolute ethanol was added, under a nitrogen atmosphere, 0.8 g of 5% platinum on charcoal. The suspension was then stirred under a hydrogen atmosphere at 23° C. until hydrogen absorption ceased (2.75 h; 423 ml; theory, 437 ml). Filtration through diatomaceous earth did not remove all colloidal particles. The evaporated filtrate was dissolved in 50 ml of ethyl acetate--methylene chloride (1:1) and was then percolated through a column of 20 g of silica gel using the same solvent mixture. Evaporation of the solvents gave 8.7 g (99%) of 1α,3β-diacetyloxychol-5-en-24-oic acid methyl ester as a white solid, mp 108°-113° C. An analytical sample, recrystallized from methanol, had mp 110.5°-112° C.

Provenance & Evidence