title: Biotransformation of two ent-Pimara-9(11),15-diene derivatives by Gibberella fujikuroi.
abstract: The incubation of 19-hydroxy-13-epi-ent-pimara-9(11),15-diene (4) with Gibberella fujikuroi gave 8 alpha,19-dihydroxy-9 alpha,11alpha-epoxy-13-epi-ent-pimara-15-ene (6), 7-oxo-11 alpha,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (7), 7-oxo-11beta,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (9), and 8 alpha,19-dihydroxy-9 alpha,11 alpha:15,16-diepoxy-13-epi-ent-pimarane (11), while the feeding of 13-epi-ent-pimara-9(11),15-diene-19-oic acid (5) with this fungus afforded 1-oxo-2 alpha,9 alpha-dihydroxy-13-epi-ent-pimara-11,15-dien-19-oic acid (13), 1-oxo-2 beta,9 alpha-dihydroxy-13-epi-ent-pimara-11,15-dien-19-oic acid (14), 13-epi-ent-pimara-9(11),15-dien-1,19-dioic acid 1,2-lactone (15), and 1-oxo-12 beta-hydroxy-13-epi-ent-pimara-9(11),15-dien-19-oic acid (16). In both biotransformations, the main reaction was the epoxidation of the 9(11)-double bond, followed by rearrangement to afford allylic alcohols. The formation of lactone 15 represents the first time that a Baeyer-Villiger oxidation has been observed in a microbiological transformation with this fungus.
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: Ricardo
authors.initials: R
authors.lastname: Guillermo
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: D045784:Abietanes / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D001711:Biotransformation; D005874:Gibberella / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010084:Oxidation-Reduction; D013237:Stereoisomerism
chemical_list: D045784:Abietanes