Syntheses of hydantocidin and C-2-thioxohydantocidin Original Research Article

Hydantocidin (12), a naturally occurring strong herbicide, was synthesized in 35.2% overall yield, with accompanying 5-epi-hydantocidin (12′) in 9.6% overall yield via isothiocyanate (13) and spiro-hydantoin (10) from 2,3-O-isopropylidene-d-ribono-1,4-lactone (1). C-2-Thioxo-hydantocidin (24) was also synthesized in 16.5% overall yield with accompanying 5-epi-C-2-thioxohydantocidin (24′, 9.2% yield) via isothiocyanate (22).