Penipratynolene, a novel nematicide from penicillium bilaiae Chalabuda.

New acetylenic nematicidal compound, penipratynolene (1), methy (2'R)-4-(2'-hydroxy-3'-butynoxy)benzoate, together with two known compounds, 6-methoxycarbonylpicolinic acid (2) and 2,6-pyridinedicarboxylic acid (3), were isolated from the culture filtrate of Penicillium bilaiae Chalabuda. The structures of 1-3 were established by spectroscopic methods. The absolute configuration of 1 was confirmed by using a modified version of Mosher's method. Compounds 1-3 showed nematicidal activity of 77%, 52%, and 98%, respectively, by a bioassay at 300 mg/l with the root-lesion nematode Pratylenchus penetrans.