Regioselective one-step synthesis of hexahydroxy permethylated beta-cyclodextrin and unambiguous NMR analysis

摘要

A highly-regioselective DIBAL-promoted hexa-de-O-methylation on the secondary rim of permethylated P-cyclodextrin directly gave an one-step'access to 2~A,3~B,2~C,3~D,2~E,3~F-hexahydroxy-heptakis (2,3,6-tri-O-methyl) beta-cyclodextrin,the position of six free hydroxy groups being unambiguously determined by NMR analyses.