| Abstract: | Five new compounds, including a novel lactone, machilactone (=rel‐(2R,3aR,6E,6aS)‐2‐heptadecyl‐3a‐methyl‐6‐octadecylidene‐6,6a‐dihydrofuro2,3‐d]1,3]dioxol‐5(3aH)‐one; 1 ), a new sesquiterpene, 3,4‐dihydroxy‐β‐bisabolol (=rel‐(1R,2S,4R)‐1‐(1R)‐1,5‐dimethylhex‐4‐enyl]‐1‐methylcyclohexane‐1,2,4‐triol; 2 ), a new secobutyrolactone, methyl (2E)‐2‐(1‐hydroxy‐2‐oxopropyl)eicos‐2‐enoate ( 3 ), two new butyrolactones, machicolide A ( 4 ) and machicolide B ( 5 ) (=3E,4R,5R)‐ and (3Z,4R,5R)‐4,5‐dihydro‐4‐hydroxy‐5‐methoxy‐5‐methyl‐3‐octadecylidenefuran‐2(3H)‐one, resp.) as a mixture, together with known caryophyllene oxide (=4,12,12‐trimethyl‐9‐methylene‐5‐oxatricyclo8.2.0.04,6]dodecane), hexacosane, tetracosanoic acid, isomahubanolide‐23 (=(3E,4R)‐4,5‐dihydro‐4‐hydroxy‐5‐methylidene‐3‐octadecylidenefuran‐2(3H)‐one), and β‐bisabolol (=(1S)‐1‐(1S)‐1,5‐dimethylhex‐4‐enyl]‐4‐methylcyclohex‐3‐en‐1‐ol) were isolated from the stem wood of Machilus zuihoensis. The structures of these compounds were established by spectroscopic studies. The eicos‐2‐enoate ( 3 ) and β‐bisabolol exhibited marginal cytotoxicity against NUGC and HONE‐1 cancer cell lines in vitro. |
