P-D-Methyl glucoside

L. M. J. Kroon-Batenburg and J. Kroon, Biopolymers, 29,1243 (1990). Solvent Effect on the Conformation of the Hydroxymethyl Group Established by Molecular Dynamics Simulations of Methyl-p-D-Glucoside in VChter. 

Thus, refluxing methyl P-D-glucoside two equivalents of tributyltin oxide, [(C4Hg)3Sn]20 and molecular sieves (3 A) in chloroform for 2-3 h followed by treatment with two equivalents of bromine at 0 °C furnishes methyl p-D-3-dehydro-3-ketoglucoside in more than 90% yield. Similarly, methyl p-D-xyloside gives the 3-oxo compound, whereas methyl a-D-glu-coside, a-D-galactoside, a-D-xyloside, and p-L-arabinoside yield 70-80% of the corresponding 4-keto derivatives [734],... 

COf shows the expected selectivity for the anomeric hydrogens of methyl p-D-glucoside and cellobioside, reacting with the latter at a rate of 7 X 10 M s at 20 °C i.e. about five orders of magnitude slower than OH). However, when cellulose (as cotton linters ) was used as a substrate, hydrogen abstraction was indiscriminate, possibly because intrinsic chemical reactivities were counterbalanced by relative accessibility. ... 

Methylenedioxy-6-methoxyaiistolactam (91) was prepared from the methyl ester of aristolochic acid Ilia (4) by Zn-AcOH reduction, and it was also obtained by treatment of the methyl ether of tuberosinone (33) with sodium hydroxide (46,85). Similarly, 3,4-methylenedioxy-6-methoxyaristolactam-Al-P-D-glucoside (92) can be obtained from tuberosinone-iV-p-D-glucoside (86). 

Pinoresinol, 1-acetoxy, 4"-methyl ether-4 -O-P-D-glucoside (+) Bk 55°E02i Pinoresinol, l-acetoxy-4"-0-methyl ether (+) Bk 46.4° l ... 

Depending on the alkoxide concentration, either the methyl jS-D-glucoside (12) or the anhydride (13) arises from 2-deoxy-2-p-toluenesulfonamido-i8-D-glucopyranosyl fluoride (10). - The presumed intermediate imine [(H)] has not been isolated. 

The sirupy oxidation product from methyl 4,6-di-O-methyl-a-D-glucoside formed a crystalline ethanolate, which could be recrystallized from methanol, and which formed a mono-p-nitrobenzoate treatment of the etha-nolate with water gave the original, sirupy hemialdal. 

When methyl jS-D-glucoside is treated with methyl sulfate and sodium hydroxide, and the product is hydrolyzed by dilute hydrochloric acid, there is obtained a tetra-O-methyl-D-glucose. This compound is a cyclic hemiacetal which, in solution, exists in equilibrium with a little of the open-chain form (Fig. 34.13, p. 1102). 

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