L,2:5,6-di-O-isopropyliden-a-D-allofuranose

Carbohydrate triflates. Triflates of carbohydrates can be prepared in high yield by reaction with triflic anhydride. Thus the reaction of (1), l,2 5,6-di-O-isopropylidene-a-D-allofuranose, with triflic anhydride in pyridine at -15° gives the triflate (2) in 80% yield. When (1) is refluxed with triflic anhydride in... 

The fused oxazole derivative 100 was synthesized from 3-azido-3-deoxy-l,2 5,6-di-O-isopropylidene-a-D-allofuranose, the key final step being the reaction of methyl 3-amino-3-deoxy-5,6-0-isopropylidene-p-D-alloside with DMF dimethyl acetal. The annelated pyranoside 101 was obtained by cyclization of a branched chain hexosulose derivative, and the fused triazole-piperidinoses such as 102 were made by a radical cyclization of a 3-pyrazolo-6-iodo-sugar derivative. The spiro-isoxazohne 103 and related isomers have been synthesized by dipolar cycloadditions of mesitonitrile oxide to 2-deoxy-2-C-methyl-ene-pentonic acids, themselves available in five steps from D-mannitol. Intra-... 

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