Allosamidin disaccharides

In 1986 the novel chitinase inhibitor (—)-allosamidin was discovered in fermentation broths of Streptomyces sp. 1713 by Sakuda and coworkers.1 (—)-Allosamidin is unusual inasmuch as it contains two N-acetyl-D-allosamine residues glycosidically linked P-1,4 to one another. In turn, this disaccharide is connected to a cyclopentanoid known as (—)-allosamizoline in the manner shown in Figure 11.1. 

The chitinase inhibitor allosamidine is a trisaccharide analogue with two N-acetylallosamine units bonded to a highly functionalized cyclopentano-oxazoline unit - allosamizoline. Analogues have now been described with one JV-acetylallo-samine unit, with the disaccharide bonded to an alternative hydroxyl of the cyclopentane, and thirdly with the oxazoline ring inverted. ... 

The synthesis of caitNidisacchaTide 121 wUdi is related to the D-allobiose disaccharide of allosamidine and hence to carbocyclic analogues of the insecticide, have been described. The aminoqnJitol unit was constructed using a Farrier reaction. ... 

A total synthesis of ( )-allosamizoline from a symmetrical trisubstituted cyclopentene has been reported, and a synthesis of allosamidin and its (1- 3) linked isomer includes a review of the preparation of the starting aminocyclitol and disaccharide moieties. The synthesis of allosamizoline and allosamidin and isomers is also mentioned in Chapters 3 and 18. 

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