Dimeric γ-lactone derivatives from the soil-derived fungus Lasiodiplodia theobromae NSTRU-PN1.4.

Investigation of the soil-derived fungus Lasiodiplodia theobromae NSTRU-PN1.4 resulted in the isolation of five dimeric γ-lactones including two new botryosphaerilactones D and E (4 and 5) and three known structurally related analogoues (1-3) along with seven known compounds. Their structures were elucidated by extensive spectroscopic analysis. The absolute configuration of 1-5 was determined by comparison of the ECD data with those of the structurally related monomeric γ-lactones. For biological evaluation, this is the first report on antifungal activity of the known (3 R,4R)-4-acetyl-3-methyl-2(3H)-dihydrofuranone which displayed weak antifungal activity against Cryptococcus neoformans with an MIC value of 200 µg/mL.