A Pair of New Polyketide Enantiomers from Three Endolichenic Fungal Strains Nigrospora sphaerica,Alternaria alternata,and Phialophora sp

Abstract

A pair of new enantiomeric polyketides, (-)- and (+)-nigrosporaol A (1a and 1b), along with one related known compound, (±)-alternarienoic acid (2), were isolated from three endolichenic fungal strains, Nigrospora sphaerica (No.83-1-1-2), Alternaria alternata (No.58-8-4-1), and Phialophora sp.(No.96-1-8-1). Their structures, including the absolute configurations, were elucidated on the basis of spectroscopic methods, X-ray diffraction analysis, and the modified Mosher's method.

Keywords

Polyketide Enantiomer Nigrosporaol A Nigrospora sphaerica Alternaria alternata

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