Cyclization, of hexose derivatives

It is not known whether the cyclization of hexose derivatives takes place with the C4- or the C5-hydroxyl group work on model compounds suggests that both the furanoid and the pyranoid rings are possible. Imino-lactone formation is theoretically possible for any 4- or 5-hydroxy nitrile,... 

Crystallography, of melezitose, II, 14 Cuto-cellulose, III, 187 Cyanohydrins, in synthesis of higher-C sugars, I, 1-36, 37, 38 Cyclization, of hexose derivatives, III, 53 Cycloamyloses, III, 254 305 V, 266 Cyclohexane, 1,3-diamino-2,4,5,6-tetra-hydroxy-. See Streptamine. 

However, despite many attempts,it is only within the last few years that progress has been made toward the successful cyclization of hexose derivatives to inositol derivatives. Ferndndez, Izquierdo and Martinez " have reported the presence of a cyclase in the leaves of Lactuca virosa L. which converts D-glucose to a material giving the Scherer test for inositol. Since this color test is general for the inositols a definite statement regarding the nature of the product will have to await its isolation and identification. 

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