ABSTRACT
Two new 10-membered lactones, namely, multiplolides A (1) and B (2), were isolated from the broth extract of the fungus Xylaria multiplex BCC 1111. Chemical structures of 1 and 2 were elucidated on the basis of their spectral data. Multiplolides A (1) and B (2) exhibited antifungal activity against Candida albicans with IC(50) values of 7 and 2 microg/mL, respectively. Both 1 and 2 were inactive in the screening systems toward the malarial parasite Plasmodium falciparum (at 20 microg/mL) and were not cytotoxic to BC-1 and KB cell lines (at 20 microg/mL).
Subject(s)
Antifungal Agents/isolation & purification , Lactones/isolation & purification , Animals , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Ascomycota/chemistry , Candida albicans/drug effects , Candida albicans/metabolism , Cells, Cultured/drug effects , Humans , KB Cells/drug effects , Lactones/chemistry , Lactones/pharmacology , Magnetic Resonance Spectroscopy , Molecular Structure , Plasmodium falciparum/drug effects , Plasmodium falciparum/metabolism , Stereoisomerism , Structure-Activity Relationship , ThailandABSTRACT
Bioassay-guided fractionation of the cell extract of the insect pathogenic fungus Aschersonia tubulata BCC 1785 led to the isolation of dustanin (1), 3 beta,15 alpha,22-trihydroxyhopane (3), 5 alpha,8 alpha-epidioxy-24(R)-methylcholesta-6,22-diene-3 beta-ol (6), together with the new 3 beta-acetoxy-15 alpha,22-dihydroxyhopane (4). Chemical structures of these compounds were elucidated by spectral analyses as well as chemical transformation. Compounds 1 and 4 exhibited antimycobacterial activity with the minimum inhibitory concentration (MIC) of 12.5 micrograms/ml.
