Marchaetoglobins A-D: Four Cytochalasans with Proangiogenic Activity from the Marine-Sponge-Associated Fungus Chaetomium globosum 162105.

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.