High-Efficiency Synthesis of N,N ' -Diacetyl-β-Chitobiosyl Allosamizoline

The high-efficiency synthesis of N,N'-diacetyl-β-chitobiosyl allosamizoline 2 was investigated. The Nbenzyloxycarbonyl (Cbz) protected trichloroacetimidate donors 11 and 13 were synthesized by routine method. The solidphase synthesis was performed using polystyrene as support and o-nitrobenzyl ether tether as linker. The target allosamidin analogue 2 was efficiently obtained by iterative glycosylation reactions, catalytic hydrogenation, acetylation, deacetylation, and photolysis, respectively.