SEARCH Articles Figures Tables 7a-Hydroxy-l-methylene-8a-pyrrolizidine Chloro-8-hydroxy-1,2-methylene-3[ -7-from Hydroxy coumarins 812 -methylene compounds Hydroxy methylene group Hydroxy methylenes Hydroxy methylenes L-Hydroxy-8-methylene-4-phenylperhydropyrido oxazine, oxidation Methylenation of a-hydroxy ketone