Microbial transformations of gelomulide G: a member of the rare class of diterpene lactones

M Iqbal Choudhary; Humaira Y Gondal; Ahmed Abbaskhan; Atta-ur-Rahman

doi:10.1002/cbdv.200590112

Microbial transformations of gelomulide G: a member of the rare class of diterpene lactones

Chem Biodivers. 2005 Oct;2(10):1401-8. doi: 10.1002/cbdv.200590112.

Authors

M Iqbal Choudhary¹, Humaira Y Gondal, Ahmed Abbaskhan; Atta-ur-Rahman

Affiliation

¹ H.E.J. Research Institute of Chemistry, International Center for Chemical Sciences, University of Karachi, Karachi-75270, Pakistan. hej@cyber.net.pk

PMID: 17191941
DOI: 10.1002/cbdv.200590112

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.

MeSH terms

Aspergillus niger / metabolism*
Cunninghamella / metabolism*
Diterpenes / chemistry
Diterpenes / metabolism*
Lactones / chemistry
Lactones / metabolism*
Molecular Structure

Substances

3,6-diacetoxy-8,14-epoxyabiet-13(15)-en-16,21-olide
Diterpenes
Lactones