Biotransformation of Two ent-Pimara-9(11),15-diene Derivatives by Gibberella fujikuroi

• Published in: Journal of natural products (Washington, D.C.) D.C.), 2009-01, Vol.72 (1), p.87-91
• Main Authors: Fraga, Braulio M, Guillermo, Ricardo, Hernández, Melchor G, Chamy, María C, Garbarino, Juan A
• Format: Article
• Language: English
• Subjects: acetates; Baeyer-Villiger oxidation; Bioconversions. Hemisynthesis; Biological and medical sciences; Biotechnology; Biotransformation; Calceolaria; Calceolaria polifolia; chemical structure; Diterpenes, Abietane - chemistry; Diterpenes, Abietane - isolation & purification; Diterpenes, Abietane - metabolism; epoxidation; Fundamental and applied biological sciences. Psychology; Gibberella - chemistry; Gibberella - metabolism; Gibberella fujikuroi; Methods. Procedures. Technologies; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; oxidation; Oxidation-Reduction; spectral analysis; Stereoisomerism
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np800647v

The incubation of 19-hydroxy-13-epi-ent-pimara-9(11),15-diene (4) with Gibberella fujikuroi gave 8α,19-dihydroxy-9α,11α-epoxy-13-epi-ent-pimara-15-ene (6), 7-oxo-11α,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (7), 7-oxo-11β,19-dihydroxy-13-epi-ent-pimara-8(9),15-diene (9), and 8α,19-dihydroxy-9α,11α: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-2α,9α-dihydroxy-13-epi-ent-pimara-11,15-dien-19-oic acid (13), 1-oxo-2β,9α-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-12β-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.