| Autor: |
Thanabalasingam D; National Institute of Fundamental Studies, Kandy, Sri Lanka., Dissanayake D; National Institute of Fundamental Studies, Kandy, Sri Lanka., Samarakoon K; National Institute of Fundamental Studies, Kandy, Sri Lanka., Kumar NS; National Institute of Fundamental Studies, Kandy, Sri Lanka., Adikaram N; National Institute of Fundamental Studies, Kandy, Sri Lanka., Jayasinghe L; National Institute of Fundamental Studies, Kandy, Sri Lanka., Araya H; School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan., Fujimoto Y; National Institute of Fundamental Studies, Kandy, Sri Lanka.; School of Agriculture, Meiji University, Kawasaki, Kanagawa, Japan. |
| Abstrakt: |
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, (3 R ,4 R )-4-hydroxymellein, (3 R ,4 S )-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. |
