Glucose, 2-acetamido-4-0- chloride

Acetamido-2-deoxy-D-glucose, reaction with acetyl chloride, 46,1... 

In order to construct the L-asparagine derivative of per-O-acetylated 0-(2-acetamido-2-deoxy-/ -D-glucopyranosyl( 1 — 4)-2-acetamido-2-deoxy-D-glucose (7), Spinola and Jeanloz (13) used (the sensitive) silver azide for conversion of the a-chloro anomer of the chitobiose derivative 8 into the / -azido derivative 9. Kunz and associates (14,15) have accomplished the conversion of the a-chloro anomer of 8 into 9 using sodium azide in the presence of tri-n-octyl-methylammonium chloride as a phase-transfer catalyst in chloroform water. 

The formation of these products from the dialkyl dithioacetals falls into two categories. The first group comprises compounds readily formed (or isolated), and is confined to derivatives of D-glucose, D-glucuronic acid, 2-acetamido-2-deoxy-D-glucose, and D-ribose. The products are obtained in high yield the formation is generally accomplished in aqueous solution, with one mole of mercuric chloride per mole of dithioacetal, and the solution is kept neutral. 

Suitable material is available from Pfanstiehl Laboratories, Waukegan, Illinois. It may also be prepared from the hydrochloride of 2-amino-2-deoxy-D-glucose (D-glucosamine) in 95% yield by the facile procedure of Inouye and co-workers.2 The 2-acetamido-2-deoxy-D-glucose should be dried at 25° (1 mm.) for at least 12 hours before use. If this material is in the form of a powder rather than compact crystals, more acetyl chloride... 

The direct one-step preparation of 2-acetamido-3,4,6-tri-0-acetyl-2 -deoxy-a-D-glu copyranosyl chloride was reported by Micheel and co-workers,3 and the described procedure is essentially the method of Horton and Wolfrom.4 The product was first prepared through a two-step route from 2-amino-2-deoxy-D-glucose hydrochloride by Baker and co-workers,5 and a number of adaptations of this method have been described6-8... 

Amino groups in dithioacetals undergo normal substitution reactions. Conventional reactions have been reported to occur with acetic anhydride,88,90,91 benzoyl chloride,46,92 l-fluoro-2,4-dinitrobenzene,250 p-toluenesulfonyl chloride,247 and benzyloxycarbonyl chloride92 the reported92 application of sodium chloride and methyl iodide to the conversion of 2-amino-2-deoxy-D-glucose diethyl dithioacetal hydrochloride into a pentamethyl derivative is presumed to be an error. Although crude 2-acetamido-2-deoxy-D-glucose diethyl dithioacetal was in one instance converted in low yield into a poorly... 

Amino-3-deoxy-a-D-glucopyranosyl)-2-deoxystreptamine (88) was synthesized by Umezawa and coworkers and by Nakajima and coworkers. In both of the syntheses, the isopropylidene derivative (85) of l,3-di-IV-(benzyloxycarbonyl)-2-deoxystreptamine was prepared as a key intermediate. (It is noteworthy that protection of the trans hydroxyl groups was achieved by an acetal-exchange reaction. - ) Also, the tri-0-benzylglycosyl chloride (86) of 3-acetamido-3-deoxy-D-glucose ... 

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