Asymmetric syntheses of the methyl glycosides of 2-deoxy-2-aminohexoses: D-allosamine, D-mannosamine, D-idosamine and D-talosamine

作者：Davies Stephen G^*; Fletcher Ai M; Foster Emma M; Lee James A; Roberts Paul M; Thomson James E; Waul Michael A

来源：Tetrahedron, 2014, 70(40): 7106-7119.

DOI：10.1016/j.tet.2014.06.019

• Aminosugars
• 2-Deoxy-2-aminohexoses
• Lithium amide
• Conjugate addition
• Asymmetric synthesis

A range of the methyl glycosides of 2-deoxy-2-aminohexoses, comprising D-allosamine, D-mannosamine, D-idosamine and D-talosamine, were prepared from the corresponding D-aldopentoses via a seven step synthetic sequence. The doubly diastereoselective conjugate addition of the requisite antipode of lithium N-benzyl-N-(alpha-methylbenzyl)amide and in situ enolate oxidation with the requisite antipode of camphorsulfonyloxaziridine (CSO) was used as the key, stereodefining step. Sequential reduction of the resultant alpha-hydroxy-beta-amino esters and oxidative cleavage of the C(1) C(2) diol unit furnished the corresponding alpha-amino aldehydes. Subsequent N- and O-deprotection gave the target compounds (as mixtures of anomers) in good yield and high diastereoisomeric purity.

• 出版日期2014-10-7