Cleavage, glucosidic linkage

Using a similar reaction sequence P-(l—>4)-glucosidic linkages were very effectively installed on the support using 4-O-TBS-protected glucosyl phosphate donor 59. Thus, repetitive glycosylation and deprotection furnished trisaccharide 62 in 53% overall yield from 54 after cleavage from the resin (Scheme 6.11). 

To account for the fact that Ci apparently has a much greater affinity for crystalline cellulose than Cx, we suggest that while Cx action causes the first cleavage of the glucosidic linkage, Ci is actually already in position awaiting the approach of Cx. In other words, Ci is an affinity factor, but it is different from that envisaged by Leatherwood in that it is also involved in the hydrolytic process. 

In our previous works (1 -3) the possibility of the generation of macro- and polyradicals on the cellulosic support, under the cold plasma conditions, by the dehydrogenation of OH groups or the cleavage of 1,5 glucoside linkages was evidenced. 

Scott G (1994) Environmental biodegradation of hydrocarbon polymers. In Doi Y, Fukuda K (eds) Biodegradable plastics and polymers. Elsevier Science BV, Amsterdam Lai YJ (1981) Kinetics of base catalyzed cleavage of glucosidic linkages. In The Ekman Days 1981, vol 2 Int. Symp. Wood Pulp Chem, Stockholm, p 26... 

Bacillus subtilis a-amylase immobilized on a phenol-formaldehyde resin displayed exo-activity, which might result from steric hindrance between the immobilized enzyme and substrates of high molecular weight (e.g. amylopectin). Thus, cleavage of the peripheral D-glucosidic linkages produced small oligosaccharides only. 

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