Novel spiciferone derivatives from the fungus Drechslera hawaiiensis isolated from the marine sponge Callyspongia aerizusa

From the marine sponge Callyspongia aerizusa collected from the Sea of Bali, Indonesia, fungal isolates of Drechslera hawaiiensis were obtained. Culture filtrates of the fungus yielded four spiciferone derivatives which include spiciferone A (1) and B (2), and two other novel derivatives including spiciferol A (3) which is an alcohol congener of spiciferone A (1) and compound 4 which is an monocyclic spiciferone congener featuring a butoxyl side chain. The structures of the novel compounds were established on the basis of NMR spectroscopic (1H, 13C, COSY) and mass spectrometric (EIMS) data.