| isolation, structural analyses and biological activity assays against chronic lymphocytic leukemia of two novel cytochalasins - sclerotionigrin a and b. | two new cytochalasins, sclerotionigrin a (1) and b (2) were isolated together with the known proxiphomin (3) from the filamentous fungus aspergillus sclerotioniger. the structures and relative stereochemistry of 1 and 2 were determined based on comparison with 3, and from extensive 1d and 2d nmr spectroscopic analysis, supported by high resolution mass spectrometry (hrms). compounds 2 and 3 displayed cytotoxic activity towards chronic lymphocytic leukemia cells in vitro, with 3 being the most ac ... | 2014 | 25006786 |