A convergent and stereoselective approach for the synthesis of C1-C11, C12-C22, and C23-C28 fragments of cytotoxic natural products cruentaren A and B are accomplished. Highlights of the strategy include a Sharpless epoxidation followed by a regioselective opening of epoxide to generate anti and syn-stereochemistry at C9-C10 and C15-C16, an Alder-Rickert reaction between a 1,5-dimethoxy-1,4-cyclohexadiene
Regioselectivity of the reactions of trialkylaluminum reagents with 2,3-epoxyalcohols: Application to the synthesis of α-chiral aldehydes
作者:William R. Roush、Michael A. Adam、Steven M. Peseckis
DOI:10.1016/s0040-4039(00)81660-3
日期:1983.1
Treatment of optically active 2,3-epoxyalcohols with trialkylaluminum reagents followed by periodate cleavage constitutes a convenient synthesis of α-chiral aldehyde derivatives, especially when the branching alkyl group is methyl.
An enantioselective total synthesis of the 14-memberedmacrolideantibiotic ingramycin, , is described. In a convergent approach three chiral fragments , and are assembled, the allylic bromide deriving its chirality from -serine while the asymmetric centres in sulfones and are introduced the Sharpless enantioselective epoxidation technique. After coupling of these fragments and a highly efficient macrolactonisation
Studies toward the Synthesis of Iejimalides A–D: Preparation of the C3–11 and C12–C24 Fragments
作者:Gowravaram Sabitha、Ch. Gurumurthy、Jhillu Yadav
DOI:10.1055/s-0033-1340083
日期:——
The convergent synthesis of the C3-C11 and C12-C24 fragments of the iejimalides A-D is described. The C3-C11 fragment is obtained by a cross-metathesis reaction, while the C12-C24 fragment is derived from a Still-Gennari modified Horner-Wadsworth-Emmons olefination.