Citrinadin A, a Novel Pentacyclic Alkaloid from Marine‐Derived Fungus Penicillium citrinum.

Abstract

A novel pentacyclic alkaloid, citrinadin A (<b>1</b>), was isolated from the cultured broth of the fungus <i>Penicillium citrinum</i>, which was separated\nfrom a marine red alga, and the structure was elucidated by spectroscopic data. The relative stereochemistry of the pentacyclic core was\nassigned on the basis of NOESY data and <sup>1</sup>H−<sup>1</sup>H coupling constants, and the presence of an <i>N</i>,<i>N</i>-dimethyl-l-valine residue in <b>1</b> was determined\nby chiral HPLC analysis of the hydrolysate.