5- amino-, 4,5-dideoxy

Nucleophilic Displacement Reactions in Carbohydrates. Part XI. Reaction of Methyl 6-Deoxy-2,3-O-isopropylidene-4-O-methyl-sulphonyl-a-L-talopyranoside with Sodium Azide A Synthesis of L-Perosamine (4-Amino-4,6-dideoxy-L-mannose) Derivatives, J. S. Brimacombe, O. A. Ching, and M. Stacey, J. Chem. Soc. C, (1969) 1270-1274. 

Several mono-carba-oligosaccharidic alpha amylase inhibitors, such as acarbose and its homologs, amylostatins, trestatins, oligostatins, adipo-sins, and so on, have been isolated from cultures of micro-organisms, and considerable interest in the biochemistry and chemistry of this class of inhibitors has been stimulated. The characteristic core-structure for inhibitory action is composed of a trihydroxy(hydroxymethyl)cyclohexene moiety and a 4-amino-4,6-dideoxy-D-glucopyranose moiety, bonded by way of an imino linkage at the allylic position. A similar structural unit has been found in the antibiotic validamycins. 

The multi-enzyme system was recently utilized for the synthesis of dTDP-4-keto-6-deoxy-a-D-glucose 3 and dTDP-P-L-rhamnose 5 generating dlTP from dTMP by dTMP kinase and acetate kinase [66, 71]. Further combination with GerB, a dTDP-4-keto-6-deoxy-D-glucose aminotransferase, gave dTDP-4-amino-4,6-dideoxy-D-glucose [72]. 

Participation of the ring-oxygen atom has also been postulated,124 to account for the stereospecific formation of L-mannopyranoside (40) and D-allofuranoside (41) products in the deamination, by way of 39b, of methyl 4-amino-4,6-dideoxy-2,3-0-isopropylidene-a-L-man-nopyranoside (39a). Ring contraction to give furanoside products pre-... 

The protonated amino group, however, has no nucleophilic activity, and does not form a hemiacetal an amino sugar can, therefore, be obtained, as a salt, in an otherwise unfavorable form. For example, 6-amino-6-deoxy-L-sorbose can be isolated as the hydrochloride of a furanose form (22) (presumably a). In alkaline solution, immediate ring-expansion to the pyranose form (23) occurs127 this reaction can be reversed under strongly acidic conditions. 4-Amino-4,6-dideoxy-D-glucose hydrochloride forms a 35 65 mixture of the a- and / -pyranose forms in solution.128... 

Amino-4,6-dideoxy-D-mannose hydrochloride (perosamine) forms an — 45 55 mixture of the a- and / -pyranose forms in solution.52 For 2-amino-2,6-dideoxy-D-glucose 6-sulfonic acid, the a / pyranose ratio is 68 32 at 20°, indicating [p. 47] that, in solution, the sugar is zwitterionic.53... 

Amino-4,6-dideoxy-D-glucose, as well as its N-methyl homologs, has been isolated from various bacterial strains. 4-Amino-4,6-dideoxy-D-glucose has been synthesized in two ways. Methyl... 

Methyl 4-amino-4,6-dideoxy-D-galactoside (119) was prepared by the reaction of 116 with azide, followed by reduction. The tetraacetate of 119 gives, on hydrolysis with 3 M hydrochloric acid,... 

Perosamine was obtained as an amorphous hydrochloride on hydrolysis of perimycine, and possesses the structure of a 4-amino-4,6-dideoxy-D-mannopyranose hydrochloride. Methyl 4,6-dideoxy-4-(dimethylamino)-a-L-mannopyranoside is formed by the ring opening of methyl 3,4-anhydro-6-deoxy-a-L-talopyranoside with dimethyl-amine. Other naturally occurring 4-amino sugars are a 2,4-diamino-... 

Glucopyranose, 4-acetamido-1,2,3,6-tetra-O-acetyI-4-deoxy-D-, 187 —, 5-amino-5-deoxy-D-, 116,132,133 —, 4-amino-4,6-dideoxy-/3-D-, 153 —, 1,4-anhydro-a-D-, from cellulose on heating, 441,442 —, 1,6-anhydro-jS-D-effect of flame retardants on pyrolysis of, 471... 

---