Citric Acid → HCID 68148479, compound

Participants

Reaction Steps

To a solution of 12 parts of 11-hydroxy-9,15-dioxoprosta-8(12),13-dienoic acid in 28 parts of ethanol, cooled to 0°-5°, is added dropwise a solution of 3 parts of triethylamine in 275 parts of water. To that mixture is added dropwise with cooling and stirring a solution of 0.32 part of sodium borohydride in 32 parts of water. Stirring at approximately 10° is continued for about 25 minutes, at the end of which time the reaction mixture is poured carefully into excess aqueous citric acid. Extraction with ether affords an organic solution, which is washed with water, dried over anhydrous sodium sulfate and concentrated under reduced pressure to afford 11,15-dihydroxy-9-oxoprosta-8(12),13-dienoic acid. This mixture of epimeric 11-hydroxy compounds is separated by chromatography on silica gel. Elution with 30% ethyl acetate in chloroform affords epimer A, characterized by an ultraviolet absorption maximum at about 277 millimicrons with a molecular extinction coefficient of about 24,400. Further elution of the column with 50% ethyl acetate in chloroform yields epimer B, characterized by an ultraviolet absorption maximum at about 277.5 millimicrons with a molecular extinction coefficient of about 23,400.

Provenance & Evidence