Marchaetoglobins A-D: Four Cytochalasans with Proangiogenic Activity from the Marine-Sponge-Associated Fungus...

Four new cytochalasans, marchaetoglobins A-D (1-4), along with five known compounds (5-9), were isolated from the marine-sponge-associated fungus Chaetomium globosum 162105. Compounds 1-4 represent examples of 19,20-seco-chaetoglobosins, of which compound 1 is the first furan-containing cytochalasan. Their structures and absolute configurations were elucidated by extensive spectroscopic analyses and electronic circular dichroism calculations. Compounds 5, 8, and 9 displayed weak to moderate antibacterial activities against Bacillus thuringiensis, Edwardsiella piscicida, Vibrio alginolyticus, and Pseudomonas syringae pv. actinidiae with minimum inhibitory concentration values ranging from 5 to 25 μg/mL. In addition, compounds 2, 3, and 5 showed potent in vivo proangiogenic activity in transgenic zebrafish, comparable to the positive control.