Nematicidal alkaloids and related compounds produced by the fungus Penicillium cf. simplicissimum

A new nematicidal alkaloid, peniprequinolone (1), together with the known a lkaloids penigequinolones A and B (2a,2b), 3-methoxy-4-hydroxy-4-(4'-methox yphenyl)quinolinone (3), and 3-methoxy-4,6-dihydroxy-4-(4'-methoxyphenyl)qu inolinone (4), were isolated from Penicillium cf. simplicissimum (Oudemans) Them. Cyclopenin (5) and a compound (6a/6b) structurally related to cyclop enin also were isolated from the fungus, and their structures were establis hed by spectroscopic analysis. The biological activities of 1, 2, 3, 4, and 5 were examined by a bioassay with root-lesion nematodes.