The first asymmetric synthesis of all four isomers of cis- and trans-3,4-dihydroxy-3,4-dihydromollugin
作者:Naga Venkata Sastry Mudiganti、Sven Claessens、Norbert De Kimpe
DOI:10.1016/j.tetlet.2008.09.138
日期:2008.12
Asymmetric synthesis of all the four stereoisomers of cis-3,4-dihydroxy-3,4-dihydromollugins 4 and 6 and trans-3,4-dihydroxy-3,4-dihydromollugins 5 and 7 was achieved. The O-methoxymethyl mollugin derivatives were dihydroxylated to (−)- and (+)-cis-3,4-dihydroxy-3,4-dihydromollugin derivatives using both AD-mix-α and AD-mix-β. Deprotection of the MOM-ethers of cis-dihydroxy compounds resulted in the
实现了顺式-3,4-二羟基-3,4-二氢软体动物4和6以及反式-3,4-二羟基-3,4-二氢软体动物5和7的所有四个立体异构体的不对称合成。使用AD-mix-α和AD-mix-β将O-甲氧基甲基mollugin衍生物二羟基化为(-)-和(+)-顺式-3,4-二羟基-3,4-二氢mollugin衍生物。顺式-二羟基化合物的MOM醚的脱保护导致目标的立体异构体(-)-(3 R,4 R)-顺式-3,4-二羟基-3,4-二氢mollugin 4,(-)-(3 R,4 S)-反式-3,4-二羟基-3,4-二氢mollugin 5,(+)-(3 S,4 S)-顺式-3,4-二羟基-3,4-二氢mollugin 6和(+) -(3 S,4 R)-反式-3,4-二羟基-3,4-二氢软胶7。这些途径铺有很多困难,例如,底物与AD混合物不相容,反式-二羟基化合物的意外形成以及脱保护方案的失败。