ABSTRACT Three previously undescribed compounds ( 1 – 3 ), including an unusual pyridazine derivative, one sesquiterpenoid, and a polyketide with novel stereochemistry, together with 24 known compounds ( 4 – 27 ), were isolated from the deep‐sea‐derived Penicillium limosum ZEN48. The structures of the new compounds were elucidated by comprehensive analyses of one‐ and two‐dimensional nuclear magnetic resonance, high‐resolution electrospray ionization mass spectrometry, and optical rotation calculation. Compounds 13 , 18 , and 19 exhibited considerable inhibitory effect in osteoclast formation at 20 µM in bone marrow‐derived monocytes, indicating their potential application in anti‐osteoporotic therapy.
Zhang et al. (Sun,) studied this question.