title: Microbial transformation of 18-hydroxy-9,13-epi-ent-pimara-7,15-diene by Gibberella fujikuroi.
abstract: The incubation of the diterpene 18-dihydroxy-9,13-epi-ent-pimara-7,15-diene (3) with the fungus Gibberella fujikuroi gave 14 metabolites, 4 and 6-18. The carbons functionalized were the C-20 methyl and all the secondaries, except C-12. The main reaction observed was the epoxidation of the 7,8-double bond, which rearranged to form 7-keto derivatives, such as 10-17, or the allylic alcohol 18. Compound 9 was the only one obtained in which the 7,8-double bond of the substrate remained unaltered. This work confirms that, in the feeding of this type of diterpene with this fungus, the oxidation at C-19, typical of the biosynthesis of gibberellins from ent-kaur-16-ene, is inhibited.
authors.affiliation: Instituto de Productos Naturales y Agrobiología, CSIC, P.O. Box 195, 38206-La Laguna, Tenerife, Canary Islands, Spain. bmfraga@ipna.csic.es
authors.forename: Braulio M
authors.initials: BM
authors.lastname: Fraga
authors.forename: Pedro
authors.initials: P
authors.lastname: González
authors.forename: Melchor G
authors.initials: MG
authors.lastname: Hernández
authors.forename: María C
authors.initials: MC
authors.lastname: Chamy
authors.forename: Juan A
authors.initials: JA
authors.lastname: Garbarino
mesh_terms: D001711:Biotransformation; D004224:Diterpenes / Q000737:chemistry / Q000378:metabolism*; D005874:Gibberella / Q000737:chemistry / Q000378:metabolism*; D005875:Gibberellins / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: C476740:18-hydroxy-9,13-epi-ent-pimara-7,15-diene; D004224:Diterpenes; D005875:Gibberellins