title: Microbial transformations of gelomulide G: a member of the rare class of diterpene lactones.
abstract: Microbial transformation of gelomulide G (3beta,6beta-diacetoxy-8beta,14beta-epoxyabiet-13(15)-en-16,12-olide, 1) was carried out. Incubation of 1 with Aspergillus niger afforded two new metabolites, 3beta,6beta-diacetoxy-8beta,14beta-dihydroxyabiet-13(15)-en-16,12-olide (2) and 3beta,6beta-diacetoxy-14beta-hydroxyabieta-8(9),13(15)-dien-16,12-olide (3). While Cunninghamella elegans afforded the 14-epimer of 2, i.e., 3beta,6beta-diacetoxy-8beta,14alpha-dihydroxyabiet-13(15)-en-16,12-olide (4), along with 3beta-acetoxy-6beta-hydroxy-8beta,14beta-epoxyabiet-13(15)-en-16,12-olide (5). The structures of the transformed products 2-5 were deduced to be new on the basis of MS and NMR data.
authors.affiliation: H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan. hej@cyber.net.pk
authors.forename: M Iqbal
authors.initials: MI
authors.lastname: Choudhary
authors.forename: Humaira Y
authors.initials: HY
authors.lastname: Gondal
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abbaskhan
mesh_terms: D001234:Aspergillus niger / Q000378:metabolism*; D020093:Cunninghamella / Q000378:metabolism*; D004224:Diterpenes / Q000737:chemistry / Q000378:metabolism*; D007783:Lactones / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure
chemical_list: C517886:3,6-diacetoxy-8,14-epoxyabiet-13(15)-en-16,21-olide; D004224:Diterpenes; D007783:Lactones