(R)-goniothalamin:: total syntheses and cytotoxic activity against cancer cell lines

The total syntheses of (R)-goniothalamin (1), a styryl lactone isolated from several Goniothalamus species, via catalytic asymmetric allylation of alpha-benzyloxyacetaldehyde (2), followed by ring-closing metathesis and Wittig olefination and via catalytic asymmetric allylation of trans-cinnamaldehyde (12), followed by ring-closing metathesis are reported. The anti proliferative activities of (R)-1 and its Z-isomer 10 as well as of the synthetic dihydropyranone intermediates 7 and 8 against eight different cancer cell lines are also described. (c) 2005 Elsevier Ltd. All rights reserved.