Reaction of Aldonolactones with Ammonia and Related Nucleophiles

Reaction of Aldonolactones with Ammonia and Related Nucleophiles 

Reaction of the Lactone Group with Ammonia and Amines 

Aldonamides are readily prepared by reaction of lactones with liquid ammonia (86,99,100), with ammonium hydroxide (101,102), or by bubbling ammonia gas into alcoholic solutions of the sugar lactones (103-104). Aldonamides of the tetronic adds are stable in aqueous solution (105), but penton- or hexon-amides are hydrolyzed, as shown by the change of the optical rotation of the amide solutions (106). The hydrolysis is catalyzed by acids and bases, and the product was the ammonium salt of the aldonic acid. 

Lactonic disaccharides (such as lactobiono-1,5-lactone) reacted with long-chain primary amines to yield model glycolipids of a new type (111,112). For the formation of JV-substituted aldonamides from aldonic acids and amines, A-V -dicylohexylcarbodiimide was employed as the condensing agent. However, no catalyst was needed in the case of the lactones. 

The synthetic glycolipids (for example 99) were obtained crystalline from ethanol. 

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VII. Reaction of Aldonolactones with Ammonia and Related Nucleophiles... 

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