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.
Département de Chimie Organique, Université de Yaoundé I, Yaoundé, Cameroon. ttabopda@yahoo.fr
Turibio K
TK
Tabopda
Gislain W
GW
Fotso
Joseph
J
Ngoupayo
Anne-Claire
AC
Mitaine-Offer
Bonaventure T
BT
Ngadjui
Marie-Aleth
MA
Lacaille-Dubois
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