17 Alpha, 21-dihydroxy-steroid 17-monoesters prepn. - by 17-esterifying 21-phosphates and enzymatically dephosphorylating

摘要

17-Monoesters of 17alpha, 21-dihydroxy-steroids, e.g., prednisone 17-formate, are prepd. by (a) esterifying the corresp. 17alpha, 21-dihydroxy-steroid 21-phosphate with suitable acylating agent under very mild conditions so that only the 17alpha-hydroxy gp. is directly esterified and (b) subsequently sephosphorylating the resulting 17alpha-acyloxy-21-phosphate by enzymatic hydrolysis with an acid phosphatase at regulated pH. Certain specified prodts. are new and claimed cpds. Under the mild conditions employed, substantially complete 17-acylation can be achieved without affecting any other OH gps. which may be present in the molecule. the 21-dephosphorylation is highly selective.