Affinity-labelling corticoids I. Synthesis of 21-Chloroprogesterone, Deoxycorticosterone 21-(1-Imidazole) Carboxylate, 21-Deoxy-21-Chloro Dexamethasone, and Dexamethasone 21-Mesylate, 21-Bromoacetate, and 21-Iodoacetate

Abstract The efficient and unambiguous preparation of several C-21 substituted affinity-labelling corticoids are described. Included is an improved procedure for the preparation of 21-chloroprogesterone and the first reported synthesis of deoxycorticosterone 21-(1-imidazole) carboxylate. Dexamethasone derivatives prepared include separate and unambiguous synthesis of 21-deoxy-21-chlorodexamethasone and dexamethasone 21-mesylate, as well as the first reported synthesis of dexamethasone 21-bromoacetate and dexamethasone 21-iodoacetate.