Glucose selective methylation

Over the years, different methods have been developed for selective methyl protonation. An early trial used protonated pyruvate as the sole carbon source [18] and produced samples highly protonated at the methyl sites of Ala, Val, Leu and He (y2 only), while most other sites were highly deuterated. Recently, it has been reported that using protonated glucose as the sole carbon source [19] resulted in 50% of all the methyl groups labelled as CHD2, which could be selectively detected with a modified constant-time HSQC. These methods can be use-... 

MeSSiMe3 or PhSSiMe3, Znl2, Bu4N I. In this case the 6-O-methyl ether was cleaved selectively from permethylated glucose. 

A study of the reductive cleavage of a series of alkoxymethyl ethers using the glucose backbone shows that, depending on the reagent, excellent selectivity can be obtained for deprotection vs. methyl ether formation for most of the common protective groups. ... 

Turanose is readily purified by recrystallization from hot methyl alcohol, in which it is moderately, though slowly, soluble. In preparing the sugar, the first stage of the hydrolysis of melezitose by an acid solution is carried out under well controlled conditions, and is followed by the removal of the D-glucose from its mixture with turanose. This is usually accomplished by a selective fermentation with yeast, but an... 

HC104-Si02 selectively cleaves terminal isopropylidene groups of the diisopropyl-idene derivatives of D-glucose, D-allose, and methyl D-gluconate in high yield. 

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