Title: Oryzanigral: a new polyketide from an endophytic fungus Nigrospora oryzae isolated from Coccinia grandis.
Authors: Thanabalasingam, D.; Dissanayake, Dilhara; Samarakoon, Kavindya; Kumar, N. Savitri; Adikaram, Nimal; Jayasinghe, Lalith; Araya, Hiroshi; Fujimoto, Yoshinori
Abstract: A new heptaketide named oryzanigral (1) was isolated from the fermentation extract of the endophytic fungus Nigrospora oryzae isolated from the leaves of Coccinia grandis, along with five known compounds, (R)-mellein, (R)-O-methylmellein, (3R,4R)-4-hydroxymellein, (3R,4S)-4-hydroxymellein and abscisic acid. The structure of oryzanigral was elucidated by spectroscopic analyses including 2D-NMR. A plausible biosynthetic pathway involving Diels-Alder reaction was proposed for compound 1 and related polyketides previously reported. In addition, structure revision of the double bond geometry for coicenal A was described.
Subjects: ENDOPHYTIC fungi; DOUBLE bonds; ABSCISIC acid; DIELS-Alder reaction; POLYKETIDES
Publication: Natural Product Research, 2024, Vol 38, Issue 15, p2703
ISSN: 1478-6419
Publication type: Academic Journal
DOI: 10.1080/14786419.2023.2191196

Oryzanigral: a new polyketide from an endophytic fungus Nigrospora oryzae isolated from Coccinia grandis.

Thanabalasingam, D.; Dissanayake, Dilhara; Samarakoon, Kavindya; Kumar, N. Savitri; Adikaram, Nimal; Jayasinghe, Lalith; Araya, Hiroshi; Fujimoto, Yoshinori