Asymmetric Synthesis of Double Bond Isomers of the Structure Proposed for Pyrinodemin A and Indication of Its Structural Revision

摘要

Asymmetric synthesis of double bond isomers (+)->2 (Δ^15’,16’) and (+)->3 (Δ^14’,15’) of the structure (>1) (Δ^16’,17’) proposed for pyrinodemin A, a cytotoxic bis-pyridine alkaloid with a unique cis-cyclopent[c]isoxazolidine moiety from a marine sponge, has been accomplished. Pyrinodemin A was indicated to be a 1:1 racemic mixture of >2 from comparison of C18 and chiral HPLC analysis for pyrinodemin A and the synthetic compounds as well as ESIMS data of oxidative degradation products of pyrinodemin A.