Synthesis of octopus glycosides: core molecules for the construction of glycoclusters and carbohydrate-centered dendrimers

Allyl α-d-glucopyranoside was perallylated to allyl 2,3,4,6-tetra-O-allyl-α-d-glucopyranoside and this was converted into an array of uniformly functionalized spacer glycosides of an “octopus” type, taking advantage of the rich chemistry of the allyl ether function. Thus, carbohydrate-derived pentaaldehydes, pentaalcohols and pentaamines with different spacer lengths were obtained by ozonolysis, reductive amination, hydroboration or photoaddition of cysteamine hydrochloride, respectively. The new octopus glycosides are useful core molecules for the synthesis of glycoclusters and for the construction of carbohydrate-centered dendrimers.