Double reductive amination of l-arabino-hexos-5-uloses: A diastereoselective approach to 1-deoxy-d-galactostatin derivatives

✍ Scribed by Pier Luigi Barili; Giancarlo Berti; Giorgio Catelani; Felicia D'andrea; Francesco De Rensis; Leonardo Puccioni

• Book ID: 104207633
• Publisher: Elsevier Science
• Year: 1997
• Tongue: French
• Weight: 639 KB
• Volume: 53
• Category: Article
• ISSN: 0040-4020
• DOI: 10.1016/s0040-4020(97)00063-x

✦ Synopsis

The double reductive amination of L-arabino-hexos-5-ulose with benzhydrylamine and NaBH3CN takes place in a diastereospecific manner giving in moderate chemical yield (36 %) the galactosidase inhibitor 1-deoxy-D-galactostatin. The aminocyclization of 2,6-di-O-benzyl-L-arabino-hexos-5-ulose is more complicated giving results dependent from the type of amine: with ammonia or methylamine a mixture of C-5 epimeric l-deoxyazapyranoses (D-galacto/L-ahro ratio --4:1) is obtained in 45-65 % combined yield, while with benzhydrylamine substantial amounts of an acyclic 1-deoxy-1-benzydrylamino-hexitol (10 % yield) is isolated together with the expected 1-deoxyazasugars of the D-galacto and L-ahro series.