A facile two-step high yield approach to 2-oxasteroids
作者:Aryeh A. Frimer、Judith Hameiri-Buch、Shlomo Ripshtos、Pessia Gilinsky-Sharon
DOI:10.1016/s0040-4020(01)88175-8
日期:1986.1
generating rapidly (< 4 hrs) and in highyield the corresponding enol (2-hydroxy-3-oxo-Δ1,4 analog) When the reaction is then allowed to continue at room temperature for several days, the enol is further autoxidized to the related lactol (1-hydroxy-2-oxa-3-oxo-Δ4 analog) in overall yields generally in the range of 85–95%. Sodium borohydride reduction of the lactol yields the pharmacologically important