Acyl Derivatives of Disaccharides

In 1935, Zemplen applied the Wohl reaction to octa-O-acetylcello-biononitrile,40 and obtained amorphous, nitrogenated substances that he supposed to be acetamido derivatives. His aim being the demonstration of the structure of the reducing disaccharides through successive degradation of their acylated nitriles to the lower aldo-biose, he discontinued these studies. 

The first work with fully acetylated aldobioses was published in 1936 by Zechmeister and Toth,41 who dissolved octa-O-acetylcello-biose in liquid ammonia, and maintained this mixture for 48 h at 55°. From the syrupy reaction-products, they isolated an N-acetylcello-biosylamine and, by subsequent acetylation of the residue, the peracetate of l,l-bis(acetamido)-l-deoxycellobiitol. For this compound, the authors proposed41 alternative structures that were later42 rejected. 

From the reaction of octa-O-acetylcellobiose with 40% methanolic ammonia for 120 h at 50°, Micheel and coworkers43 isolated dicello-biosylamine, cellobiosylamine, and the same N-acetylcellobiosyl-amine previously described by Zechmeister and Toth.41 

In 1963, a series of systematic studies was begun on the reaction of fully acylated disaccharides (acetates and benzoates) with methanolic or aqueous solutions of ammonia at room temperature. Octa-O-acetyl-a-cellobiose in 16% methanolic ammonia afforded44 1,1-bis-(acetamido)-l-deoxycellobiitol (45) and N-acetyl-a-cellobiosylamine (46), which is the anomer of the cellobiosylamine previously described by Zechmeister and Toth41 and Micheel and coworkers.43 

Likewise, octa-0-acetyl-/3-lactose in 16% methanolic ammonia45 afforded l,l-bis(acetamido)-l-deoxylactitol (47) and N-acetyl-a-lac-tosylamine (48). The anomer of the latter compound had previously been obtained by Kuhn and Kruger,46 either by reaction of ketene with 

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