3-Amino-3,6-dideoxy galactose

Deoxy-L-galactose 19, 3-amino-2,3-dideoxy-L-xylo-hexose 20 and L-diginose 21 are synthesized conveniently from the aldehyde 18 (35). 

An analogous reaction of UDP-2-acetamido-2,6-dideoxy-D-xy/o-hexos-4-ulose (7d) results in formation of the derivatives of 2-acetamido-2,6-dideoxy-D-glucose and -D-galactose.166 These amino sugars were identified as components of several O-specific polysaccharides (for reviews, see Refs. 95 and 167). 

Uridine diphosphate galactose (109) was prepared using seven enzymes involved in three biosynthetic pathways, immobilised on super-bead columns. This method, which converted 50% of uracyl monophosphate into UDP-galactose (109), was superior to the solution approach as enzyme stability was improved. To study the biosynthesis of the pseudosaccaharide acarbose, thymidine 5 -diphospho-4-amino-4,6-dideoxy-a-D-glucopyranose(110) was synthesised from galactose in sixteen steps. 

The presented review describes total syntheses directed towards 6-amino-6,8-dideoxy-D-eryt/iro-D-galacto-octose, commonly named lincosamine - the sugar component of the antibiotic lincomycin. In the first part we present total syntheses of lincosamine that start from carbohydrate precursors. The D-galactose-derived aldehyde is the most frequently used synthon. In the second part, total syntheses of lincosamine from non-carbohydrate precursors are presented. This part of the review is divided into two subsections. The first one groups syntheses based on the application of furan compounds. In the second one we present a hetero-Diels-Alder approach to the synthesis of lincosamine. 

Amino-2-deoxy-P-D-mannopyranurono-syl-(1 4)-2-amino-2,6-dideoxy-a-L-galac-topyranosyl-(1 ->3 )-2-amino-2,6-dideoxy-L-galactose, 9CI... 

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