Secondary metabolites from leaves of Knema pachycarpa possessing cytotoxic and acetylcholinesterase inhibitory activities

Abstract Phytochemical study of Knema pachycarpa leaves led to the isolation of ten compounds. Their chemical structures were determined as (7” R , 8” R )‐hydnocarpin D ( 1 ), (7” R , 8” R )‐hydnocarpin ( 2 ), sinaicitin ( 3 ), (‐)‐globulol ( 4 ), β ‐caryolanol ( 5 ), phytol ( 6 ), biochanin A ( 7 ), chrysoeriol ( 8 ), tanoside II ( 9 ) and astragalin ( 10 ) using NMR and MS spectral data. Among the isolates, (7” R , 8” R )‐hydnocarpin ( 2 ) showed good cytotoxic activity against KB, HepG‐2, Lu and MCF‐7 cancer cell lines with IC 50 values from 13.99±0.62 μg/mL to 30.65±1.44 μg/mL. Compound 4 showed selective cytotoxicity against LU cancer cell line and significant acetylcholinesterase (AChE) inhibition with IC 50 values of 12.31±0.51 μg/mL and 5.12±0.22 μg/mL, respectively.