Cytotoxic Long-chain Alkene and Terpene Isolated from the Methanol Extract of the Air-dried Leaves of Pipturus arborescens C.B. Rob

A long-chain alkene (1-hexacosene) and a terpene were obtained from the bioactive methanol extract of the air-dried leaves of Pipturus arborescens (Link) C.B. Rob (“Handalamay”) collected from Poblacion, Kapatagan, Lanao del Norte. The compounds were isolated through extraction with ethanol, sequential partitioning with water-chloroform and hexane-90% methanol followed by fractionation and purification with repeated gravity column chromatography using gradient mixtures of hexane: ethyl acetate (1:1 ratio). The structures of the isolates were elucidated on the basis of spectroscopic data: ¹H-and ¹³C-NMR, ¹H-¹³C Heteronuclear Multiquantum Correlation (HMQC), ¹H-¹³C Heteronuclear Multibond Correlation (HMBC), ¹H-¹H Homonuclear Correlation Spectroscopy (COSY), Infra-Red Spectroscopy (IR), Ultraviolet-Visible Spectroscopy (UV-VIS) and Mass Spectrometry (MS). The isolated compounds were shown to possess moderate cytotoxic activity against the brine shrimp Artemia salina (Leach).