A Convenient Method for Retro-Cycloaddition of Adducts from Steroidal 5,7-Dienes and 4-Phenyl-1,2,4-triazolidine-3,5-dione and Application to the Syntheses of Biosynthetic Intermediates of Ergosterol.
作者:Yoji TACHIBANA
DOI:10.1248/cpb.46.1454
日期:——
Use of 1, 8-diazabicyclo[5.4.0]undec-7-ene (DBU) in boiling xylene was found to be a convenient method for the retro-cycloaddition of adducts of 4-phenyl-1, 2, 4-triazolidine-3, 5-dione (PTAD) with steroidal 5, 7-dienes. This process was applied to the syntheses of ergosta-5, 7, 24(28)-trien-3β-ol and ergosta-5, 7, 22, 24(28)-tetraen-3β-ol.
在沸腾的二甲苯中使用1, 8-二氮杂双环[5.4.0]十一烯(DBU)被发现是一种便捷的方法,用于4-苯基-1, 2, 4-三氮唑-3, 5-二酮(PTAD)与固醇5, 7-二烯加合物的逆环加成。这一过程被应用于合成ergosta-5, 7, 24(28)-三烯-3β-醇和ergosta-5, 7, 22, 24(28)-四烯-3β-醇。