ABSTRACT
The antimicrobial substances in sunflower (Helianthus annuus) were investigated. Two antifungal benzopyran derivatives, 6-acetyl-2,2-dimethyl-1,2-benzopyran (1) and 6-acetyl-7-hydroxy-2,2-dimethyl-1,2-benzopyran (2), were isolated from the ethanol extract of sunflower receptacles. The antimicrobial activities of isolated compounds 1 and 2 and their related compounds (precocenes) were evaluated by the paper disk method, using Pyricularia oryzae as the test fungus.
Subject(s)
Anti-Infective Agents/isolation & purification , Benzopyrans/isolation & purification , Helianthus/chemistry , Anti-Infective Agents/pharmacology , Antifungal Agents/isolation & purification , Antifungal Agents/pharmacology , Benzopyrans/pharmacology , Helianthus/ultrastructure , Microbial Sensitivity TestsABSTRACT
(+)-Eucamalol (1) and (-)-1-epi-eucamalol (2) were synthesized from (S)-(-)-perillaldehyde to determine the absolute configuration of 1, the structure of natural (+)-eucamalol being determined to be (1R,6R)-(+)-3-formyl-6-isopropyl-2-cyclohexen-1-ol. (+)-Eucamolol (1) and its 1-epimer (2) exhibited significant repellent activity against Aedes albopictus, and inhibited its feeding as well as DEET.
