Total Synthesis of Natural PI-091, a New Platelet Aggregation Inhibitor of Microbial Origin
作者:Ryota Shiraki、Akihiko Sumino、Kin-ichi Tadano、Seiichiro Ogawa
DOI:10.1021/jo951897z
日期:1996.1.1
The total synthesis of a new platelet aggregation-inhibiting gamma-lactam PI-091 (1) gave a 1:1 diastereomeric mixture at the gamma-ketal carbon. The high-yielding aldol reaction of an appropriately protected 1,3,4-trihydroxy-4-methyldecan-2-one 42, prepared from D-glucose, with the kinetically generated enolate of 3-methyl-2-butanone provided 43. The resulting diastereomeric mixture of the aldol adduct
新的抑制血小板聚集的γ-内酰胺PI-091(1)的总合成在γ-缩酮碳上得到了1:1的非对映异构体混合物。由D-葡萄糖制得的,得到适当保护的1,3,4-三羟基-4-甲基十二烷-2-酮42与动力学生成的3-甲基-2-丁酮的烯醇化物的高产率羟醛反应提供了43。通过分子内缩酮化随后脱水将得到的醛醇加合物43的非对映异构混合物转化为2,4-烷基化的呋喃45。在光化学条件下,向45衍生的α-三甲基甲硅烷基化的呋喃48中添加单线态氧可有效地提供α,γ-二烷基化的γ-羟基γ-内酯47。由47制备的甲基缩酮52转化为γ-羟基γ-内酰胺通过暴露于MeOH中的液氨获得53。通过侧链仲羟基的Dess-Martin高碘烷氧化,从52实现了1的总合成。本总合成显示天然1中侧链的立体碳中心为S.