Synthesis of iminopolyols via Henry reaction: a short route to the α-manno- sidase inhibitor 1,4-dideoxy-1,4-imino-D-mannitol and to amino analogues†,1
A chiral nitronate dianion from (=d)-glyceraldehyde. Enantiospecific syntheses of 2,3-dideoxy-3-nitro furanosides and pyranosides
作者:Theresa M. Williams、Harry S. Mosher
DOI:10.1016/s0040-4039(01)84574-3
日期:——
A new enantiospecific protocol for the synthesis of 2,3-dideoxy-3- nitro and 3-amino sugars is reported. Chiral nitronate dianion 3, derived from (+)-(=d)-glyceraldehyde, is allylated and the resulting adduct 7 is transformed to either the methyl furanoside 9 or the methyl pyranoside 10 depending on the reaction sequence.
Reaction of urea-hydrogen peroxide complex with trifluoroaceticanhydride in acetonitrile at 0°C affords in a safe and easy fashion anhydrous solutions of peroxytrifluoroacetic acid. These can be used to oxidize aldoximes to nitroalkanes in good yields. Ketoximes fail to react in these conditions and are cleaved to the parent carbonyl compounds.
Synthesis of iminopolyols via Henry reaction: a short route to the α-manno- sidase inhibitor 1,4-dideoxy-1,4-imino-D-mannitol and to amino analogues†,1
The α-mannosidase inhibitor 1,4-dideoxy-1,4-imino-D-mannitol (DIM) as well as amino analogues of DIM and of deoxy-manno-nojirimycin, respectively, have been prepared using a diastereoselective nitroaldol addition as the key step.