Function-Oriented Synthesis toward Peloruside A Analogues.

A convergent and rapid synthesis of original C2,C3-unsaturated, C11,C13-keto-enol macrocycles with a peloruside A skeleton has been developed. These original unsaturated macrocycles constitute valuable platforms to access peloruside A analogues with high diversity. The four-fragment strategy implemented features two aldol-type couplings with the central C12-C14 building block TES-diazoacetone and a late-stage ring-closing metathesis. Enantiopure analogue 18ab showed antiproliferative activity in the low micromolar range on NCI and MCF7 tumor cell lines.

Toward a total synthesis of the novel polyketide natural product spiculoic acid A.

[chemical reaction: see text]. An enantioselective approach toward the recently isolated marine natural product, spiculoic acid A, conceptualized along the proposed biogenetic hypothesis, involving an intramolecular Diels-Alder reaction as the pivotal step, is delineated. Access to a structurally embellished bicyclic core of the natural product has been accomplished.