Alkylation of clarithromycin diacetate (I) with allyl t-butyl carbonate (II) in the presence of palladium catalyst affords the 11-O-allyl ether (III). Subsequent metathesis reaction between ally ether (III) and 1-butenyl-4-phenylimidazole (IV) employing Grubb's catalyst provides adduct (V). Finally, methanolysis of the 2'-acetate ester of (V) gives rise to the target compound.