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Patent / Jan 01, 1974
Corticosteroid 21-sulfate and phosphate esters
Source:
ZA 7203373
Betamethasone phosphate (I; R = H, R1 = OPO3H) was prepd. in 92.5% yield by treating diiodopregnadienedione I (R = R1 = iodo) with K2HPO4-H3PO4. The sulfate ester I (R = H, R1 = OSO3H) was obtained similarly.