4.5- deoxy-5-hydrazino

Only relatively few displacements of chloro groups in carbohydrate derivatives have been reported. Treatment of 6-chloro-6-deoxy-l,2 3,5-di-O-isopropylidene-a-D-glucofuranose (22) with anhydrous hydrazine for 2 days at reflux temperature yielded the corresponding 6-deoxy-6-hydrazino derivative.47 The chloro group in methyl 6-chloro-6-deoxy-a-D-glucopyranoside could be displaced by a benzoate group to afford methyl 6-O-benzoyl-a-D-glucopyranoside, in 74% yield, by... 

The synthesis of the nucleoside 594 was performed by the reaction of the hydrazino derivatives 593 with acetic anhydride at room temperature. Deacetylation of 594 gave (2-deoxy-/3-D-ribofuranosyl)triazolopyrimidine (595). Reaction of 593 with acetic formic anhydride in dry pyridine followed by treatment with ammonia/MeOH gave the triazolo[4,3-c]pyrimi-dine nucleoside 596 (91MI4) (Scheme 118). 

II) From Vinylic Ethers.—The base-catalyzed elimination of certain tosyloxy functions in carbohydrates was demonstrated as early as 1922 by Freudenberg and Brauns.118 From the reaction of 1,2 3,6-dHO-isopropyl-idene-3-O-p-tolylsulfonyl-D-glucofuranose (16) with anhydrous hydrazine, they obtained, in addition to the 3-hydrazino derivative, 3-deoxy-l, 2 5,6-di-0-isopropylidene-D-erj/(Aro-hex-3-enofuranose (17). Hydrogenation of... 

Reductive cleavage of hydrazino sugars leads to their amino analogs. Thus, methyl 3,4-0-isopropylidene-2-0-p-tolylsulfonyl- 8-L-arabinopyran-oside was converted through the hydrazino derivative, with Walden inversion,38 38b to 2-amino-2-deoxy-a-i.-ribose hydrochloride.38 The d and... 

When 3-deoxy-3-hydrazino-1,2 5,6-di-O-isopropylidene-a-D-gIuco-furanose (13) is oxidized47 in alkaline deuterium oxide, the corresponding deuterated 3-deoxy compound (14) is formed with 94%... 

A similar aromatization is observed widi 3-deoxy-3-hydrazino-D-allose. 3-Deoxy-3-hydrazino-l,2 5,6-di-0-isopropylidene-a-D-allo-furanose (147), obtained by the reaction of hydrazine with l,2 5,6-di-O-isopropylidene-3-O-p-tolylsulfonyl-a-D-glucofuranose, is quantitatively transformed into 3-(D-en/thfo-l,2,3-trihydrox)q)ropyl)pyrazole... 

Nucleophilic displacements of sulfonyloxy groups by reagents other than halide ions had also been observed in sugar chemistry. As early as 1922, a 3-deoxy-3-hydrazino derivative had been obtained by the action of hydrazine on l,2 5,6-di-0-isopropylidene-3-0-p-tolylsul-fonyl-a-D-glucofiiranose, and this derivative was later characterized " as 3-deoxy-3-hydrazino-l,2 5,6-di-0-isopropylidene-a-D-allofuranose. 

Aldotetroses, 4-acetamido-4-deoxy-, 178 Alkyl halides, carbonylation of, 61 Allofuranose, 3-deoxy-3-hydrazino-l,2 5,6 - di - O - isopropylidene - a - D -, 162, 234... 

The conversion of 3-deoxy-3-hydrazino-l,2 5,6-di-0-isopropylidene-n-allofuranose into the corresponding 3-deoxy-3-halo-D-glucose derivative by A-iodo-, A-bromo-, or A-chloro-succinimide may proceed by way of a diazonium intermediate formed by initial oxidation of the hydrazino derivative. The reaction is, however, probably more complex, as the oxidation by iodine in aqueous potassium iodide gave the gem di-iodo derivative. ... 

Amino-6-deoxy-D-glucose derivatives have been obtained both by direct interaction of methyl tri-0-acetyl-6-bromo-6-deoxy-/J-n-glucopyrano-side with ammonia, or by Raney nickel reduction of the hydrazino derivative formed from 6-chloro-6-deoxy-l,2 3,5-di-0-isopropylidene-a -D-glucofuranose. ... 

Hydrazino-Derivate von Furanosen konnen untcr aciden Bedingungen lH-PyrazoIe bilden. So wird aus 3-Deoxy-3-hydrazino-l,2 5,6-di-0-isopropyliden-a-D-glucofuranosc odcr dcr stereoisomeren Allofuranose mit konz. Salzsaure 3(5)-(1,2,3-Trihydroxy-propyl)-1 H-pyrazol erhalten1180. 

Kanamycin derivatives with a changed configuration in C-2"-position such as 2"-manno-kanamycin A, 6"-amlno-6-deoxy-2"-manno-kanamycin (161) and 6"-deoxy-6"-hydrazino-2"-maimo-kanamycin A (162) have a decreased activity compared with the parent compounds. 

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