An expedient route for semisynthetic para-modified 3'-phenyl docetaxel
analogs is described using the initial regioselective iodination of t
he oxazolidinecarboxylate 3. Palladium catalyzed coupling reactions of
the iodo intermediate 4 with alkenyl and aryl boronic acids and alkyn
es led after alkaline hydrolysis to a series of N,O-protected para-sub
stituted phenylisoserines 6. Coupling with 10-deacetyl-7,10-O-diTroc-b
accatin III followed by standard deprotections and acylation afforded
the title analogs.