Alkaloids From the Marine Fungus Lecanicillium fusisporum Using an Amino Acid-Directed Strategy

Abstract

An amino acid-directed strategy has been developed to explore the potential of marine fungi to produce alkaloids. The marine fungus Lecanicillium fusisporum was cultured in glucose-peptone-yeast (GPY) medium to which were added L-tryptophan, L-phenylalanine, L-threonine, D, L-methionine, L-serine, L-lysine and L-valine. A new indole alkaloid, lecasporinoid (1), along with five known alkaloids (2−6) were discovered from the culture broth. The planar structure of lecasporinoid (1) was determined by HR-ESIMS, and 1D and 2D NMR spectroscopic data. The absolute configuration was established by optical rotation and 13C NMR calculations combining with a chemical synthetic approach.