A series of novel derivatives of macrolide with 4''-O-mono- or disaccharides were synthesized. The corresponding glycosyl trichloroacetimidates were used as the donors in the glycosylations. The in vitro antibacterial activities of 7a-f and 13-16 against a panel of susceptible and resistant pathogens were tested. The modification of 4''-O-mono- or disaccharides may lead to the understanding of interaction of the macrolide and the bacterial ribosome.