ABSTRACT
Five new phenopicolinic acid analogues (1-5) have been isolated from solid-substrate fermentation cultures of Verticillium lecanii. The most abundant component (vertilecanin A; 1) displays antiinsectan activity against Helicoverpa zea. These compounds were obtained by chromatographic fractionation of the EtOAc culture extract and identified by analysis of NMR and MS data. The known fungal metabolites 2-decenedioic acid and 10-hydroxy-8-decenoic acid were also isolated from these cultures.
Subject(s)
Picolinic Acids/isolation & purification , Verticillium/chemistry , Amanita/chemistry , Fatty Acids, Monounsaturated/isolation & purification , Fermentation , Magnetic Resonance Spectroscopy , Mass Spectrometry , Models, Chemical , Picolinic Acids/chemistryABSTRACT
Convolvulus hystrix Vahl. (family Convolvulaceae) is a common wild plant growing in the kingdom of Saudi Arabia. It is used in traditional medicine. Our study resulted in the isolation and structural elucidation of ten natural products from which a stilbene carboxylic acid was isolated for the first time as a new natural product. The isolated products are mainly shikimates in addition to two sterols; beta-sitosterol and stigmasterol, as well as one triterpenoid, oleanolic acid. The shikimate products are vanillin, vanillic acid, syringic acid, ferulic acid, isoferulic acid, isoscopoletin and the new stilbene derivative. The structures were elucidated on the basis of spectral data from 400 MHz 1H NMR, MS, IR and UV. The biogenesis of the new stilbene is discussed.
