Novel bioactive breviane spiroditerpenoids from Penicillium brevicompactum Dierckx.
The structures of four new, naturally occurring bioactive spiroditerpenoids, (+)-breviones B, C, D, and E, potential allelopathic agents, have been determined from extracts of semisolid fermented Penicillium brevicompactum Dierckx. The structures display the novel breviane spiroditerpenoid skeleton. Structure elucidation was performed by chemical transformations and by homo- and heteronuclear 2D-NMR spectral data. On the basis of combined studies of the theoretical conformations and NOEDIFF data, their relative stereochemistry is proposed. A mixed biogenesis for this novel family of spiroditerpenoids is tendered. The levels of activity shown by breviones B, C, and E in the etiolated wheat coleoptiles bioassay, especially breviones E (100% inhibition) and C (80% inhibition) both at 10(-4) M, suggest them as lead compounds for new agrochemicals.
Macías
F A
FA
Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Cádiz, Apdo. 40, 11510-Puerto Real, Cádiz, Spain. famacias@uca.es
Varela
R M
RM
Simonet
A M
AM
Cutler
H G
HG
Cutler
S J
SJ
Dugan
F M
FM
Hill
R A
RA
D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification*; D005285:Fermentation; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008958:Models, Molecular; D010407:Penicillium / Q000737:chemistry* / Q000378:metabolism; D010937:Plant Growth Regulators / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013055:Spectrophotometry, Infrared; D013141:Spiro Compounds / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D013237:Stereoisomerism; D014908:Triticum / Q000187:drug effects / Q000254:growth & development
D004224:Diterpenes; D010937:Plant Growth Regulators; D013141:Spiro Compounds