Dimethyl sulfate, glucose reaction

Trehalose is a nonreducing disaccharide (C12H22O11) isolated from the poisonous mushroom Amanita muscaria. Treatment with an a-glucosidase converts trehalose to two molecules of glucose, but no reaction occurs when trehalose is treated with a j3-glucosidase. When trehalose is methylated by dimethyl sulfate in mild base and then hydrolyzed, the only product is 2,3,4,6-tetra-O-methylglucose. Propose a complete structure and systematic name for trehalose. 

O-MethykUioH. Quinacetophenone is converted into the dimethyl ether by alternate addition of dimethyl sulfate and aqueous sodium hydroxide to a solution of the substance In 95% ethanol. Anhydrous D-glucose on reaction in aqueous... 

The 3-methyl ethers of the 4,6-0-benzylidene and 4,6-0-ethylidene derivatives of methyl 2-(A-benzyloxycarbonyl)amino-2-deoxy-a-n-gluco-pyranoside have been prepared by a sequence of reactions paralleling Neuberger s synthesis. The d anomer of the latter compound was obtained directly by methylation of 2-(A-benzyloxycarbonyl)amino-2-deoxy-4,6-0-ethylidene-D-glucose with dimethyl sulfate and alkali. Both anomers were transformed into the free amines by catalytic hydrogenolysis. ... 

Methylation is no longer carried out with dimethyl sulfate, which was previously used. The resulting sodium chloride is rinsed away with water. The product is then spin-dried to a water content of 55-60% and subsequently homogenized and compacted in a screw extender. Ethyl cellulose is prepared in a manner analogous to that used for ethyl chloride and the reaction is taken to 2.1-2.6 ethoxy groups per glucose unit. The products serve as finishing materials in the textile industry as well as for paint bases and injection-molded articles. 

In certain of their reactions, the substances behave as Schiff bases. However, since methylation by the use of methyl iodide and silver oxide and subsequent hydrolysis of the glucosylaniline (glucose anilide) (I) lead to tetra-O-methylglucopyranose (III) 16) the compound probably has a pyranose ring 16). The identical tetra-O-methyl pyranose ether (II) was obtained by methylation of Ar-phenyl-D-glucosylamine (I) by the use of dimethyl sulfate and sodium hydroxide, though only in 25% yield 17a, b). 

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