Alkaloids from Heimia salicifolia

Two alkaloids, 9β,2′-dihydroxy-4′′,5′′-dimethoxy-lythran-12-one ( 1) and (2 S, 4 S, 10 R)-4-(3-hydroxy-4-methoxyphenyl)-quinolizidin-2-acetate ( 2) were isolated from Heimia salicifolia. Two alkaloids, 9β,2′-dihydroxy-4′′,5′′-dimethoxy-lythran-12-one or 9β-hydroxyvertine ( 1) and (2 S,4 S,10 R)-4-(3-hydroxy-4-methoxyphenyl)-quinolizidin-2-acetate ( 2), as well as seven known alkaloids, lythrine ( 3), dehydrodecodine ( 4), lythridine ( 5), vertine ( 6), heimidine ( 7), lyfoline ( 8) and epi-lyfoline ( 9), were isolated from Heimia salicifolia. The structures of these compounds were elucidated by extensive spectroscopic techniques. Furthermore, the structures of 2, 3, and 6 were confirmed by X-ray crystallography, including absolute configuration determination of 2 and 6. Compounds 6 and 9 showed moderate antimalarial activity.