Reaction of Steroid-17.ALPHA.-hydroxy-17-carboxylic Acids with Carbodiimides. Synthesis of Steroid-17-spiro-5'-(2'-imino-4'-oxazolidinones) and 17-Spiro-5'-(2',4'-oxazolidinediones).
Reaction of Steroid-17.ALPHA.-hydroxy-17-carboxylic Acids with Carbodiimides. Synthesis of Steroid-17-spiro-5'-(2'-imino-4'-oxazolidinones) and 17-Spiro-5'-(2',4'-oxazolidinediones).
Steroid-17α-hydroxy-17-carboxylic acids (2) were allowed to react with carbodiimides (DCCI, DPCI, DTCI, EDCI) to afford 17-spiro-5'-[2'-imino-4'-oxazolidinones] (3-5, 11), 17-spiro-5'-[2', 4'-oxazolidinediones] (7-9)and N-acylureas (10), depending on the reaction conditions. The reaction in acetonitrile in the presence of CuCl2 gave 3-5, while that in N, N-dimethylformamide gave 7-9. The reaction with DTCI under basic conditions afforded 10 along with 9.