A new alkaloid, speradine B (1), together with griseofulvin (2), epigriseofulvin (3), and isogriseofulvin (4), was purified from the extracts of Penicillium dipodomyicola isolated from Clerodendrum inerme, a tree from the intertidal zone of Nanhai. Their structures were elucidated on basis of extensive spectroscopic analysis.