Antimicrobial dihydroisocoumarins from Crassocephalum biafrae.
Bioassay-guided fractionation of the CHCl (3)-soluble extract of the stem bark of Crassocephalum biafrae (Asteraceae) resulted in the isolation of three new dihydroisocoumarins, named biafraecoumarins A ( 1), B ( 2), and C ( 3); two known triterpenes ( 4 and 5); and a known ceramide ( 6). The structures of the new compounds were established as 7-but-15-enyl-6,8-dihydroxy-3( R)-penta-9,11-dienylisochroman-1-one ( 1), 7-butyl-6,8-dihydroxy-3( R)-penta-9,11-dienylisochroman-1-one ( 2), and 7-butyl-6,8-dihydroxy-3( R)-pent-10-enylisochroman-1-one ( 3) using spectroscopic data. Compounds 1- 3 exhibit low to significant antimicrobial activities against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Pseudomonas picketti, Trichphyton longifusus, Aspergillus flavus, Microsporum canis, Fusarium solani, Candida albicans, and Candida glabrata.
Tabopda
Turibio K
TK
Département de Chimie Organique, Université de Yaoundé I, Yaoundé, Cameroon. ttabopda@yahoo.fr
Fotso
Gislain W
GW
Ngoupayo
Joseph
J
Mitaine-Offer
Anne-Claire
AC
Ngadjui
Bonaventure T
BT
Lacaille-Dubois
Marie-Aleth
MA
D000890:Anti-Infective Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D019659:Asteraceae / Q000737:chemistry*; D049934:Isocoumarins / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D008826:Microbial Sensitivity Tests
D000890:Anti-Infective Agents; D049934:Isocoumarins