ABSTRACT
Two undescribed steroids, named (15 R)-2,15-dihydroxypregna-1,4-dien-3,16-dione (1) and 2,15-dihydroxypregna-1,4,14-trien-3,16-dione (2), were isolated from the aerial parts of Munronia pinnata (Wall.) W. Theob. The structure elucidation of two compounds was performed by using spectroscopic methods and comparing the literature. Compound 2 exhibited inhibitory effect against PTP-1B with an IC50 value of 152.07 ± 3.33 µM, and compound 1 was inactive.
ABSTRACT
Three new cassane-type diterpenoids, namely, (4S)-6ß,12α,19-trihydroxy-cass-13(15)-en-16,12-olide (1), cass-13(15)-en-â16,12-olide (2), and 12α-hydroxy-cass-13(15)-en-16,12-olide (3), were isolated from the seeds of Caesalpinia sinensis. The structures of 1-3 were established by extensive spectroscopic analysis, and their absolute configurations were assigned by electronic circular dichroism (ECD) calculations. The inhibitory activities against PTP1B of the isolated compounds were evaluated. The results showed that compound 2 possessed PTP1B inhibitory activity with an IC50 value of 217.45 ± 36.4 µM.
