New cyclopeptide alkaloid and lignan glycoside from Justicia procumbens.

This study reported a new cyclopeptide alkaloid, justicianene A (1), and a new lignan glycoside, procumbenoside H (2), isolated from Justicia procumbens. The structures of the new compounds were elucidated by means of spectroscopic analysis, including extensive 2D NMR studies and mass spectrometry. Cyclopeptide alkaloids were first observed from the genus Justicia. Compound 2 was cytotoxic against human LoVo colon carcinoma cells with an IC50 value of 17.908 ± 1.949 μM.