14168-65-1Relevant articles and documents
Selective synthesis of 1,6-anhydro-β-D-mannopyranose and -mannofuranose using microwave-assisted heating
Hoai, Nguyen To,Sasaki, Akiyoshi,Sasaki, Masahide,Kaga, Harumi,Kakuchi, Toyoji,Satoh, Toshifumi
, p. 1747 - 1751 (2011)
The dehydration of D-mannose and the demethanolization of methyl-α-D-mannopyranoside (MαMP) or methyl-α-D- mannofuranoside (MαMF) were examined using microwave-assisted heating for a 3-min irradiation at temperature from 120 to 280 °C in ordinary or dry sulfolane without any catalyst. The microwave-assisted heating of MαMP and MαMF smoothly proceeded to selectively afford the anhydromannoses, 1,6-anhydro-β-D-mannopyranose (AMP) and 1,6-anhydro-β-D-mannofuranose (AMF), respectively, in high yields. For MαMP in ordinary sulfolane at 240 °C, AMP was selectively obtained in the AMF:AMP ratio of 4:96, whereas AMF was the major product at the AMF:AMP ratio of 97:3 from MαMF in dry sulfolane at 220 °C.
Regioselective acylation of 1,6-anhydro-β-D-manno and galactopyranose catalysed by lipases
Junot, N.,Meslin, J.C.,Rabiller, C.
, p. 1387 - 1392 (1995)
Pseudomonas fluorescens lipase (Amano) was found to be highly regioselective in the transesterification of 1,6-anhydro-β-D-manno and galactopyranose (mannosane and galactosane respectively) using vinyl acetate as an acyl donor.As in the case of 1,6-anhydro-β-D-glucopyranose (glucosane, the 4-OH axial group of mannosane is preferred, while the titled lipase catalysed the regioselective transesterification at the 2-axial OH of galactosane.The enzymatic acylation affords monoesters of the 1,6-anhydropyranoses which are difficult to obtain using conventional methods.
A Unified Strategy to Access 2- And 4-Deoxygenated Sugars Enabled by Manganese-Promoted 1,2-Radical Migration
Carder, Hayden M.,Suh, Carolyn E.,Wendlandt, Alison E.
supporting information, p. 13798 - 13805 (2021/09/07)
The selective manipulation of carbohydrate scaffolds is challenging due to the presence of multiple, nearly chemically indistinguishable O-H and C-H bonds. As a result, protecting-group-based synthetic strategies are typically necessary for carbohydrate modification. Here we report a concise semisynthetic strategy to access diverse 2- and 4-deoxygenated carbohydrates without relying on the exhaustive use of protecting groups to achieve site-selective reaction outcomes. Our approach leverages a Mn2+-promoted redox isomerization step, which proceeds via sugar radical intermediates accessed by neutral hydrogen atom abstraction under visible light-mediated photoredox conditions. The resulting deoxyketopyranosides feature chemically distinguishable functional groups and are readily transformed into diverse carbohydrate structures. To showcase the versatility of this method, we report expedient syntheses of the rare sugars l-ristosamine, l-olivose, l-mycarose, and l-digitoxose from commercial l-rhamnose. The findings presented here validate the potential for radical intermediates to facilitate the selective transformation of carbohydrates and showcase the step and efficiency advantages attendant to synthetic strategies that minimize a reliance upon protecting groups.
Catalytic Highly Regioselective C-H Oxygenation Using Water as the Oxygen Source: Preparation of 17O/18O-Isotope-Labeled Compounds
Doiuchi, Daiki,Uchida, Tatsuya
supporting information, p. 7301 - 7305 (2021/10/01)
We found that the oxygen atom of water is activated to iodosylbenzene derivatives via reversible hydrolysis of PhI(OOCR)2 and can be used to the oxygen source for ruthenium(bpga)-catalyzed site-selective C-H oxygenation. Ru(bpga)/PhI(OOCR)2/H2O system, sterically less bulky methinic and methylenic C-H bonds in various compounds can be converted to desired oxygen functional groups in a site-selective manner. Using this method, oxygen-isotope labeled compounds such as d-[3-17O/18O]-mannose can be prepared in a multigram scale.
Synthesis of unstable 4-benzoyl-1,6-anhydro-3-keto-β-D-mannopyranose via stereoselective photobromination of 2,3-isopropylidene-4-benzoyl-1,6-anhydro-β-D-mannopyranose
Mahdi, Jassem G.,Dawoud, Hanaa M.,Manning, Abigail J.,Lieberman, Harvey F.,Kelly, David R.
, p. 24 - 35 (2019/11/03)
Stereoselective photobromination of 1,6-anhydro-β-D-glucopyranose derivatives occurs at exo-H6. However, photobromination of 4-benzoyl-2,3-isopropylidene-1,6-anhydro-β-D-mannopyranose 6 produced unstable 4-benzoyl-1,6-anhydro-3-keto-β-D-mannopyranose 7. The mechanism of stereoselective oxidation at C-3 could be attributed to the facile radical proton abstraction at C-3, followed by the subsequent bromination of the isopropylidene group, which was subsequently eliminated during the aqueous workup. Thus, the aim of this article is to identify the molecular structure of the unstable compound 7.
Oligosaccharide compound and its manufacture and its intermediate
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Paragraph 0242; 0243; 0244, (2018/04/14)
The purpose of the present invention is to provide an oligosaccharide with high versatility that can produce a protected sulfate oligosaccharide that can become a manufacturing intermediate of polysulfated hyaluronic acid, and to provide a manufacturing method therefor and an intermediate thereof. Position 2 amino groups in glucosamine, galactosamine, and the like can react with saccharide receptors having an electron attracting group such as glucuronic acid and protected sulfate groups, by using a saccharide donor protected by a specific protective group.
From D-Glucose to Biologically Potent L-Hexose Derivatives: Synthesis of α-L-Iduronidase Fluorogenic Detector and the Disaccharide Moieties of Bleomycin A2 and Heparan Sulfate
Lee, Jinq-Chyi,Chang, Shu-Wen,Liao, Chih-Cheng,Chi, Fa-Chen,Chen, Chien-Sheng,Wen, Yuh-Sheng,Wang, Cheng-Chung,Kulkarni, Suvarn S.,Puranik, Ramachandra,Liu, Yi-Hung,Hung, Shang-Cheng
, p. 399 - 415 (2007/10/03)
A novel and convenient route for the synthesis of biologically potent and rare L-hexose derivatives from D-glucose is described. Conversion of diacetone-α-D-glucose (14) into 1,2:3,5-di-O-isopropylidene-β -L-idofuranose (19) was efficiently carried out in two steps. Orthogonal isopropylidene rearrangement of compound 19 led to 1,2:5,6-di-O-isopropylidene-β-L-idofuranose (27), which underwent regioselective epimerization at the C3 position to give the L-talo- and 3-functionalized L-idofuranosyl derivatives. Hydrolysis of compound 19 under acidic conditions furnished 1,6-anhydro-β-L-idopyranose (35) in excellent yield, which was successfully transformed into the corresponding L-allo, L-altro, L-gulo, and L-ido derivatives via regioselective benzylation, benzoylation, triflation and nucleophilic substitution as the key steps. Applications of these 1,6-anhydro-β-L-hexopyranoses as valuable building blocks to the syntheses of 4-methylcoumarin-7-yl-α-L-iduronic acid and the disaccharide moieties of bleomycin A2 as well as heparan sulfate are highlighted.
A carbohydrate synthesis employing a photochemical decarbonylation
Kadota, Kohei,Ogasawara, Kunio
, p. 8661 - 8664 (2007/10/03)
A new route to the aldopentoses, ribose and lyxose, and the aldohexoses, talose and gulose, has been developed using chiral building blocks containing a bicyclo[3.2.1]octane framework by employing a photochemical decarbonylation reaction as the key step.
5-exo Radical Cyclization onto 3-Alkoxyketimino-1,6-anhydromannopyranoses. Efficient Preparation of Synthetic Intermediates for (-)-Tetrodotoxin
Noya,Paredes,Ozores,Alonso
, p. 5960 - 5968 (2007/10/03)
Ketoxime ethers at C3 of 1,6-anhydro-β-D-mannopyranose derivatives were found to be useful 5-exo radical traps of alkyl and vinyl radicals generated at a chain tethered to the C2 hydroxyl group, allowing advanced synthetic intermediates for (-)-tetrodotoxin to be prepared from D-mannose in good overall yield.
On the regioselective acylation of 1,6-anhydro-β-D- and L-hexopyranoses catalysed by lipases: Structural bass and synthetic applications
Boissière-Junot, Nathalie,Tellier, Charles,Rabiller, Claude
, p. 99 - 115 (2007/10/03)
With the aim of providing new methods for the regioselective protection at the 2,3 and 4 positions of monosaccharides, we have studied the acetylation of a class of rigid sugars: the 1,6-anhydro-β-D- and L-hexopyranoses (hexopyranosanes D-1 to D-5 and L-1 to L-5), using vinyl acetate as an acyl donor and two common lipases,Candida rugosa and Pseudomonas cepacia, as catalysts. Our results indicate that the relative orientation of the hydroxyls governs the regioselectivity of acetylation. In the D-series, when the 3-OH is in the axial position, acetylation occurs mainly at the 4-axial OH, while the 2-axial OH is preferred when the 4-OH is equatorial. Conversely, when the 3-OH is equatorial, a strong selectivity affects the equatorial 2-OH. Compounds of the L-series were shown to be poor substrates for the lipase Pseudomonas cepacia except for L-galactosane for which the 2-monoacetyl ester was obtained in good yield. An attempt to rationalize the results by means of molecular modelling is also made to account for the catalytic activity of the Candida rugosa lipase on hexopyranosanes 1-3.
