N-Glucosamine

Vasella has applied the concept of anomeric anion stabilization by a nitro group to the /3-D-JV-acetyl-D-glucosamine derivative 177, available in four steps from N-acetyl-n-glucosamine [52] (Scheme 39). Reaction of the tetraethylammonium nitronate derived from 177 with aldehyde 178 provides anti-179 which then undergoes stereoselectively reduction (see Sect. 2.2.1) to provide -C-glycoside 180, intermediate in a synthesis of N-acetyl-neuraminic acid. 

Hydrolyzes chitobiose and higher analogs and protein derivatives by removing Af-acetyl-n-glucosamine from the non reducing end A /S-D-glucuronide + HzO — alcohol + D-glucuronic acid... 

CfiH]7NOs 3416-24-8) see Metrizamide a-n-glucosamine hydrochloride (Cr,H 4C1N05 14131-6)2-5) see Glucametacin glucoscillaren A... 

Elementary analyses on a variety of streptobiosamine derivatives coupled with the known structure for streptidine definitely established the formula C21H39N7O12 for streptomycin. - Since streptidine was established as C8Hi8Ne04 and N-methyl-n-glucosamine was C7H15NO5, then free streptose had the molecular formula CeHioOj. 

Acid hydrolysis of tetraacetyldidesoxydihydrostreptobiosamine - yielded N-methyl-n-glucosamine and crystalline didesoxydihydrostrep-tose. The latter substance yielded a di-p-nitrobenzoate. This compound was the first derivative in which the difficultly esterifiable hydroxyl group in the streptose portion of streptomycin was acylated. A branched carbon skeleton was established therefore for streptose and streptose was shown to be a hexose containing two aldehyde groups. 

Periodate oxidations of N-acetyldidesoxydihydrostreptobiosamine indicated a pyranose ring structure for the N-methyl-n-glucosamine por-... 

The high resistance toward acetylation of the free hydroxyl group in tetraacetyldidesoxydihydrostreptobiosamine suggested that it was tertiary in nature. On this basis, N-methyl-n-glucosamine would be attached to the C2 position of streptose and didesoxydihydrostrepto-biosamine would have the structure XX. 

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