Structural revisions of the reported A-ring phosphine oxide synthon for ED-71 (Eldecalcitol) and a new synthesis

The reported structures and synthesis of the A-ring phosphine oxide synthon and the drug ED-71 (eldecalcitol) in J. Am. Chem. Soc. (2001, 123, 3716-3722) are not correct. We made revisions of their structures and developed a new synthetic route to the A-ring phosphine oxide and ED-71.