マイクロスケールＣｒｏｓｓ Ｍｅｔａｔｈｅｓｉｓ／ＣＤ・ＦＤＣＤプロトコルによる新規天然物絶対配置決定法

Abstract

A micro-scale chemical/CD (FDCD) exciton chirality protocol has been realized for determining the absolute configuration of C=C double bond containing compounds. This method is based on the conversion of the preexisting and/or introduced double bonds into the p-substituted styrenoid chromophores and/or fluorophores via cross olefin metathesis, that function as the new CD and FDCD reporter groups. The method has been applied to a variety of natural and synthetic compounds, i.e., (i) allylic alcohols and amines, (ii) macro-cyclic molecules, (iii) unstable alcohols where acylation by Mosher's acid fail, (iv) chiral molecules bearing no other functional groups than ene moieties, in which other methods are not accessible, (v) substrates bearing the sterically hindered hydroxyls, and (vi) large compounds where two hydroxyls are separated by a long distance. Based on the established method, the configurational assignment of gymnocin-B, a new polyether marine natural product containing 15 contiguous polyether skeleton, has been realized.