4348-80-5

Upstream product

• 67-56-1 methanol 
• 112693-26-2 C₃₇H₆₂O₁₇ 
• 186581-53-3 diazomethane 
• 14917-55-6 methyl 6-deoxy-α-L-mannopyranoside 

Downstream Products

• 150966-51-1 Methyl 2,3-di-O-methyl-4-O-(2-O-acetyl-4-O-benzyl-3-O-methyl-α-L-rhamnopyranosyl)-α-L-rhamnopyranoside 

Relevant academic research and scientific papers

Regioselective methylation of methyl glycopyranosides with diazomethane in the presence of transition-metal chlorides and of boric acid

Partial methylation of the methyl pyranosides of a number of pentoses, hexoses, 6-deoxyhexoses, methyl uronates and their methyl ethers with diazomethane in the presence of transition-metal chlorides and boric acid was studied. It was found for methyl glycosides of pentoses and 6-deoxyhexoses that tin(II), antimony(III), and titanium(IV) chlorides as well as boric acid promoted substitution mainly of OH-3, but with cerium(III) and zinc(II) salts mainly substitution of OH-2 was observed. Methylation of methyl β-l-rhamnopyranoside demonstrated higher reactivity of OH-2 in all cases. The methylation of methyl glycosides of hexoses in the presence of tin(II), antimony(III) and cerium(III) chlorides gave mainly 3-methyl ethers. The 3-methyl ethers, which are not involved in further complexation, accumulated up to 50-80% of the reaction mixture (95-100% of monomethyl ether fraction). Convenient preparative syntheses of methyl ethers for a number of sugars are suggested. Copyright (C) 1999 Elsevier Science Ltd.

Comparative Studies on the Constituents of a Parasitic Plant and Its Host. III. On the Constituents of Boschniakia rossica FEDTSCH, et FLEROV. (2)

Two iridoid glucosides, namely boschnaloside (2), (+)-pinoresinol-β-D-glucopyranoside (3), a new oligosaccharide (=β-D-glucopyranosyl(1->4)-α-L-rhamnopyranosyl-(1->3)-D-(4-O-caffeoyl)-glucopyranose) (4), and a new phenylpropanoid glycoside named rossicaside A (5) have been isolated from Boschniakia rossica FEDTSCH, et FLEROV (Orobanchaceae) and their structures have been determined.Keywords--Boschniakia rossica; Orobanchaceae; boschnaloside; boschnaside; (+)-pinoresinol-β-D-glucoside; acetylated oligosaccharide; rossicaside A; phenylpropanoid glycoside

REGIOSELECTIVE ENHANCEMENT OF THE NUCLEOPHILICITY OF THE HYDROXYL GROUPSIN METHYL α-L-RHAMNOPYRANOSIDE BY COMPLEXATION WITH TIN(II) CHLORIDE

A tentative mechanism for complexanation, and a possible model of a tin(II)chloride-methyl glycoside intermediate complex, have been established largely from analysis of methyl ethers formed on methylation of methyl α-L-rhamnopyranoside and its monomethyl ethers by diazomethane in the presence of a catalytic amount of tin(II) chloride in selected solvents.The complex is mainly formed through displacement of molecules of the donor solvent coordinated to a tin(II) atom by the favorably cis-disposed, hydroxyl groups of the sugar moiety.The spatiel arrangement of the hydroxyl groups plus the distribution of atomic charges at the individual oxygen atoms of hydroxyl groups of the methyl glycoside were found to be the main factors responsible for the selectivity observed.The effect of selected solvents on the stability and/or ability to participate in the formation of the foregoing intermediate complex could not be satisfactorily clarified.

GLYCOSIDES OF MARINE INVERTEBRATES. XV. A NEW TRITERPENE GLYCOSIDE - HOLOTHURIN A1 - FROM CARIBBEAN HOLOTHURIANS OF THE FAMILY HOLOTHURIIDAE

A glycoside, holothurin A1 has been isolated from the polar glycosidic fractions of the holothurians H. floridana and H. grisea.The complete structure of the glycoside has been established; it is: 3β-3)-O-β-D-glucopyranosyl-(1->4)-O-β-D-quinovopyranosyl-(1->2)-(4-sulfato-β-D-xylopyranosyl)oxy>holosta-9(11)-ene-12α,17α,22ξ-triol.Details of the IR and 1H and 13C NMR spectra of the compounds obtained are given.