Bioactive Secolignans from Peperomia d indygulensis

• Published in: Journal of natural products (Washington, D.C.) Vol. 69; no. 5; pp. 790 - 794
• Main Authors: Wu, Jian-lin, Li, Na, Hasegawa, Toshiaki, Sakai, Jun-ichi, Mitsui, Tomokazu, Ogura, Hirotsugu, Kataoka, Takao, Oka, Seiko, Kiuchi, Miwa, Tomida, Akira, Turuo, Takashi, Li, Minjie, Tang, Wanxia, Ando, Masayoshi
• Format: Journal Article
• Language: English
• Published: American Chemical Society 26.05.2006
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np0600447

Thirteen secolignans, including eight new ones (1−8), were isolated from the EtOAc extract of Peperomia dindygulensis. The structures were mainly elucidated by 1D and 2D NMR and MS experiments, the relative configurations were determined by NOE correlations, and the absolute configurations were established by the optical rotations and CD spectra. Cytotoxicity and MDR (multidrug resistance) reversal activity of the isolated compounds were examined. Compounds 6 and 7, peperomins B (10) and E (12), showed moderate to strong growth inhibitory activity against a malignant lung tumor cell (VA-13) with IC50 values of 15.2, 13.5, 13.9, and 1.93 μM, respectively, and also inhibited the growth of a normal lung fibroblast cell (WI-38) at the same levels. Compound 7 and peperomin E (12) exhibited inhibitory activity against a liver tumor cell (HepG2) with IC50 values of 22.3 and 12.1 μM. Compounds 5 and 7 and peperomins A, B, C, and E (9−12) enhanced calcein accumulation in MDR 2780 cells at 25 μg/mL. Compounds 2, 3, 7, and peperomin E (12) showed inhibitory activity on induction of the intercellular adhesion molecule-1 (ICAM-1).