Glucose with sodium methoxide

Deoxy-D-jcylo hexose 6-(dihydrogen phosphate) (21) has also been synthesized (2) the reaction sequence makes use of 3-deoxy l 2,5 6-di-O-isopropylidene D-galactofuranose (16), a compound that can be easily prepared from D-glucose (2, 60). The mono-isopropylidene derivative (17) formed by partial hydrolysis of the di-ketal is converted into the 6-tosylate (18) by reaction with one molar equivalent of p-toluenesulfonyl chloride. From this the epoxide (19) is formed by reaction with sodium methoxide. Treatment of the anhydro sugar with an aqueous solution of disodium hydrogen phosphate (26) leads to the 6-phosphate (20)... 

Some examples will illustrate the applicability of this generalization in so far as it concerns alkaline scission. 5,6-Anhydro-l,2-isopropylidene-D-glucofuranose with alcoholic sodium hydroxide gives a mixture of isopropylidene-D-glucose and isopropylidene-L-idose. The latter results from inversion on C5, the former presumably by inversion on the non-asymmetric C6.7 3,4-Anhydro-l,2-isopropylidene-D-psicose (or allu-lose17) (XX) when treated with sodium hydroxide yields a mixture of products among which 1,2-isopropylidene-D-fructose (XIX) was detected (in the representations inversions are denoted by circles above the arrows and the carbons inverted are noted below the arrows). With sodium methoxide, however, l,2-isopropylidene-4-methyl-D-sorbose (XXI) is the chief product and results from inversion on C4.1S... 

Another method of synthesis of derivatives of 3-methyl-D-glucose lies in the scission of the anhydro-ring of 2,3-anhydro-D-allose derivatives with sodium methoxide, when the entry of the methoxyl group is accompanied by a Walden inversion on C3.82... 

Degradation of the nitrile with sodium methoxide was effected by Zempl n and Kiss, and the yield of the pentose was 40.6% of the initial n-glucose. Removal of the acetyl groups with sulfuric acid and of the nitrile group with silver carbonate lowered the yield of n-arabinose to 34%. 

There have been few investigations of the reactions of polyhydroxy compounds with alkali metal alkoxides in nonaqueous media at room temperature.. Percival" reported the preparation of D-glucose-NaOEt and D-glucose NaOMe by treating d-glucose with sodium ethoxide, and penta-O-acetyl-D-glucopyranose with sodium methoxide, respectively. The adducts were dried under vacuum at 60° for 24 hours, a treatment which would make the presence of any significant proportion of alcohol of solvation unlikely. Any traces of moisture in the preparative medium preclude the formation of an aJkoxide adduct. 

Deoxy-2-ureido derivatives of D-glucose have been known for many years,189,190 but only recently have their properties been studied in detail. The acetate esters show a marked resistance to catalytic de-O-acetylation with sodium methoxide, only the 1-O-acetyl group being removed.164 This behavior resembles that of 1,3,4,6-tetra-0-acetyl-2-deoxy-2- iV,iV-bis[2-... 

Blattellastanoside B (172) was also synthesized as shown in Figure 7.14.15 Reduction of the chloro epoxide A with diisobutylaluminum hydride was followed by acetylation to give B selectively, although the yield was only 29% with 68% of the recovered A. Treatment of B with sodium methoxide in methanol at 0°C yielded C, which afforded epoxy alcohol D by further treatment with sodium methoxide at 60 °C. Glucosylation of C with acetobromo-D-glucose was followed by deacetylation to give blattellastanoside B (172) as microcrystalline powder, mp 158-160°C. A comparison of the H- and 13C-NMR spectra of the synthetic 172 with those of blattellastanoside B proved the identity. 

Colchicoside was isolated in 0.25% yield from the seeds of C. autum-nale by Bellet (297). In a capillary the substance melted at 192-195°, but on a block the melting point was raised to 216-218°. It possesses the molecular formula CggHgjNOii and contains one acetyl and three methoxyl groups. Acid hydrolysis afforded glucose and a demethyl-colchicine which was found to be identical with Substance C (378). With sodium methoxide, colchicoside was converted to a demethyl-allocolchiceine which afforded allocolchicine on methylation (297). The demethylallocolchiceine was found to be identical with that derived from Substance C under similar conditions. The partial synthesis of... 

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