Lignans, an amide and anti-platelet activities from Piper philippinum

Investigation of the stem extract of Piper philippinum led to isolation of eight compounds, piperphilippinins I-VI (1-6), philippinamide (7) and (+)-bornyl caffeate (8) together with 26 known compounds. Among the isolates, (−)-3′,4′-O,O-demethylenehinokinin (10) and 3,4-methylenedioxycinnamaldehyde (23) showed anti-platelet activities in vitro.