A SNAr based facile synthesis of triaryl diethers, degradation products of vancomycin and related glycopeptide antibiotics

A mild and efficient procedure has been developed for the synthesis of triaryl diethers and has been applied to the synthesis of diethers I (X1 = X2 = H; X1 = X2 = Cl; X1 = H, X2 = Cl), degrdn. products from glycopeptide antibiotics of the vancomycin family. Thus, regioselective reaction of Me gallate and Me 3-nitro-4-fluorobenzoate with added K2CO3 in DMF afforded a functionalized triaryl ether which was readily converted to diethers I (X1 = X2 = H; X1 = X2 = Cl). Alternatively, protection of Me gallate with Ph2CCl2, followed by sequential reactions with the benzoate and base via various intermediates afforded diether I (X1 = H, X2 = Cl). [on SciFinder (R)]