Chitobiose, from chitin

This conclusion10 has been reached mainly from crystallographic studies on chitin and on acetylchitobiose obtained from chitin by acetoly-sis.107 The chitobiose was isolated in the form of its crystalline octa-acetate which could also be obtained108 by acetylation of the hydrolyzate produced by the action of fuming hydrochloric acid on chitin. A hen-decaaeetylchitotriose also was obtained by this procedure. 

An enzymic mediod for prq>aring chitobiose in hundred gram quantities from chitin has been... 

Sakamoto J, Kobayashi S. Enzymatic synthesis of 3-0-Methylated chitin oligomers from new derivatives of a chitobiose oxazoline. Chem. Lett. 2004 33 698-699. 

Tokuyasu, K., Ono, H., Hayashi, K., and Mori, Y. 1999. Reverse hydrolysis reaction of chitin deacetylase and enzymatic synthesis of P-D-GlcNAc-(l-4)-GlcN from chitobiose. Carbohydr Res 322 26-31. 

C,2H24N209 340.33 Isol. from the partial add hydrolysate of chitosan. Chitinases are of widespread occurrence, particularly in moulds and many of them e.g. Streptomyces griseus and Streptomyces albus degrade chitin or Af-acetylchitodextrins to N,N -diacetylchitobiose. This is subsequently hydrolysed by a separate chitobiase to chitobiose. 

Synthesis of fluorinated chitin derivatives using chitinase from Bacillus sp. as a catalyst was carried out by Kobayashi and co-workers [227]. 6 -fluoro-, 6-fluoro-and 6,6 -difluoro-chitobiose oxazoline derivatives were newly prepared as TSAS monomers for chitinase. Ring-opening polyaddition of these monomers proceeded effectively at pH 8.0-9.0 and 30-40 C, giving rise to alternating 6-fluorinated chitin derivatives and fully 6-fluorinated chitin derivatives, under total control of region selectivity and stereoselectivity. 

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