resolved by forming a mixture of the diastereomeric acetals ((−)-9 and (+)-10 or (+)-9 and (−)-10 with the title vicinal-diol((+)- or (−)-5) to give optically pure (R)(−)-3. The method for racemizing the undesired enantiomer((S)(+)-3) was also explored. Optically pure (+)-4-demethoxydauno-mycinone ((+)-2b) was elaborated from (R)(-)-3 according to the reported reaction scheme.
(±)-7-Deoxy-4-demethoxydaunomycinone(±)-3)通过形成非对映
乙缩醛((-)-9和(+)-10或(+)-9和(-)的混合物而干净地拆分-10,标题为邻位二醇((+)-或(-)-5),得到光学纯的(R)(-)-3。外消旋不需要的对映异构体((S)(+)-3)的方法根据报道的反应方案,从(R)(-)-3制备了光学纯的(+)-4-脱甲氧基
十二烷基
牛磺酸-((+)-2b)。