Hydrochloric Acid → HCID 86589030, compound

Participants

Reaction Conditions

Reaction Steps

(6S,9S,10S,11S,13S,16R,17R)-9,11-Epoxy-6-fluoro-17-hydroxy-10,13,16-trimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthrene-17-carboxylic acid (20 g) is dissolved in pyridine (50 mL) and cooled to 0° C. 3-Methylthiophene-2-carbonyl chloride (9.39 g) is added and the reaction is stirred at room temperature. After 2 hours, the reaction mixture is added dropwise to a vigorously stirred solution of 6M HCl. DCM is added, the phases are separated and the organic phase is washed with water and brine. After drying over magnesium sulphate, evaporation is followed by flash column chromatography on silica gel eluting with DCM-methanol (25:1) to afford 3-methylthiophene-2-carboxylic acid (6S,9S,10S,11S,13S,16R,17R)-9,11-epoxy-6-fluoro-17-carboxy-10,13,16-trimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthren-17-yl ester. Selected 1H-NMR signals (CDCl3) δ 0.90 (3H, d), 0.95 (3H, s), 1.40 (3H, s), 2.40 (3H, s).

Provenance & Evidence