Chemical constituents from Piper wallichii.

Fifteen known compounds including four triterpenoids (1-4), one sterol (5), one diketopiperazine alkaloid (6) and nine phenolics (7-15) were isolated from the stems of Piper wallichii. Their structures were elucidated by means of spectroscopic analysis, and acidic hydrolysis in case of the 2-oxo-3β,19α,23-trihydroxyurs-12-en-28-oic acid β-D-glucopyranosyl ester (1). The structure of compound 1 was fully assigned by 1D and 2D NMR experiments for the first time. All isolates were tested for their antibacterial, antifungal, anti-inflammatory and antiplatelet aggregation bioactivities.