Screening of Yucatecan plant extracts to control Colletotrichum gloeosporioides and isolation of a New Pimarene from Acacia pennatula.

Screening of seven Yucatecan plant extracts to look for fungicidal activity for the control of Colletotrichum gloeosporioides was carried out. Bioassay-directed purification of the root extract of one of the most active plants, Acacia pennatula, resulted in the isolation of the new compound 15,16-dihydroxypimar-8(14)-en-3-one (1), which in the in vitro bioassay "agar dilution" was shown to have growth, sporulation, and germination inhibition activity. Nuclear magnetic resonance spectroscopic techniques were used to elucidate its structure.