97-30-3Relevant articles and documents
ESIMS and NMR studies on the selective deprotection of acetylated glucosides by dibutyltin oxide
Wang, Shao-Min,Zhu, Wei-Guo,Kang, Jian-Xun,Liu, Hong-Min,Chen, Jun-Miao,Li, Cui-Ping,Zhang, Kai
, p. 203 - 209 (2011)
The reaction process for the selective deprotection of acetylated glucosides by dibutyltin oxide in methanol is investigated by using methyl 2,3,4,6-tetra-O-acetyl-α-d-glucopyranoside as a model substrate with ESIMS and NMR techniques. According to the results, it is inferred that at first, dimeric 1,3-dimethoxytetrabutyldistannoxane is formed by the reaction of dibutyltin oxide with methanol, and then the tetraorganodistannoxane reacts with the acetylated glucoside to produce glucoside-organotin complex intermediates. Finally, the complex intermediates are hydrolyzed leading to the free-OH glucoside and organotin acetate derivatives. The reaction is affected by neighboring group participation and steric hindrance, which allow for high selectivities among different acetyl groups in acetylated glucosides.
Direct Highly Regioselective Functionalization of Carbohydrates: A Three-Component Reaction Combining the Dissolving and Catalytic Efficiency of Ionic Liquids
Axelsson, Anton,Ta, Linda,Sundén, Henrik
, p. 3339 - 3343 (2016)
An unprecedented regioselective functionalization of unprotected polyols has been realized with the use of an ionic liquid NHC precatalyst. The protocol is robust, scalable, and the products can be isolated in good to excellent yields without chromatography. Moreover, the methodology enables successful recycling of the catalyst.
Biosynthesis of methyl glucoside and its antibacterial activity against Staphylococcus aureus and Escherichia coli
Kaulpiboon, Jarunee,Rudeekulthamrong, Prakarn
, (2019)
In this study, the methyl glucosides (MGn) was synthesized using β-cyclodextrin (β-CD) and methanol through the coupling reaction of recombinant cyclodextrin glycosyltransferase (CGTase) from Bacillus circulans A11. The optimal condition for the synthesis of MGn consisted of an incubation of 1.5% (w/v) β-CD and 500 U/mL of CGTase in a water/methanol solution containing 30% (v/v) methanol at pH 6.0, 50 °C for 120 h. Upon analysis by TLC, at least three MG products were observed. The molecular weight of the main transferred product was 217.08 Da; this value was in accordance with methyl monoglucoside (MG1). MG1 was produced and prepared on a large scale and subsequently purified by preparative TLC. The combined 1H- and 13C-NMR analysis confirmed that the structure of MG1 was methyl-α-D-glucopyranoside. In addition, MG1 showed emulsification activity and stability in its formation in water and n-hexadecane. The antibacterial activity of MG1 was also determined by agar disc diffusion method. The results found that the MG1 (1, 5 and 10 mg/disc) showed antibacterial activity against E. coli ATCC 25922 only, with inhibition zones of 28, 38 and 40 mm, respectively. The MIC values (mg/mL) of MG1 against S. aureus ATCC 25923 and E. coli ATCC 25922 were found to be 20.00 and 0.63, while MBC values (mg/mL) were 40.00 and 0.63, respectively.
Debenzylation of complex oligosaccharides using ferric chloride
Rodebaugh, Robert,Debenham, John S.,Fraser-Reid, Bert
, p. 5477 - 5478 (1996)
Anhydrous FeCl3 in CH2Cl2 at room temperature and 0°C has been used to debenzylate monosaccharides and oligosaccharides in yields generally greater than 70%. Notably, alkenes, acetates, benzoates, phthalimides, acyl amides, and sensitive glycosidic linkages are unaffected by the reaction conditions.
Triethylamine-methanol mediated selective removal of oxophenylacetyl ester in saccharides
Rasool, Javeed Ur,Kumar, Atul,Ali, Asif,Ahmed, Qazi Naveed
, p. 338 - 347 (2021/01/29)
A highly selective, mild, and efficient method for the cleavage of oxophenylacetyl ester protected saccharides was developed using triethylamine in methanol at room temperature. The reagent proved successful against different labile groups like acetal, ketal, and PMB and also generated good yields of the desired saccharides bearing lipid esters. Further, we also observed DBU in methanol as an alternative reagent for the deprotection of acetyl, benzoyl, and oxophenylacetyl ester groups. This journal is
SELECTIVE VALORIZATION OF BIOMASS SUGARS
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Page/Page column 47-51, (2021/06/26)
Disclosed are methods of forming an epimer or a dehydrated isomer of a pyranose monosaccharide or a pyranose saccharide residue in an oligosaccharide or a glycoside.
Carbon glycoside glycosylated tetravalent platinum compound as well as synthesis method and application thereof
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Paragraph 0064-0067, (2021/07/08)
The invention provides a carbon glycoside glycosylated tetravalent platinum compound, a synthesis method and application thereof. R1 and R2 are independently C1-C4 lower alkanes, R3 is glucose, galactose, mannose and ribose, different sugars are used as raw materials, and a series of carbon glycoside glycosylated tetravalent platinum compounds are synthesized through protection and deprotection reaction and metallization reaction of the sugars. The synthesis method is simple, the used raw materials are cheap and easy to obtain, the glycosylated tetravalent platinum compound has the capacity of targeting glucose transporter protein and has potential application value in the field of cancer treatment, introduction of a C-glucosidic bond enables the series of compounds to have the capacity of resisting hydrolysis of beta-glucosidase, and the compound is expected to be applied to the field of oral antitumor drugs.
Calixanthomycin A: Asymmetric Total Synthesis and Structural Determination
Chen, Kuanwei,Xie, Tao,Shen, Yanfang,He, Haibing,Zhao, Xiaoli,Gao, Shuanhu
supporting information, p. 1769 - 1774 (2021/03/08)
We report the first asymmetric total synthesis and structural determination of calixanthomycin A. Taking advantage of a modular strategy, a concise approach was developed to assemble the hexacyclic skeleton with both enantiomers of the lactone A ring. Stereoselective glycosylation coupled the angular hexacyclic framework with a monosaccharide fragment to produce calixanthomycin A and its stereoisomers. This enable us to determine and assign the absolute configuration of C-25 (25S) and monosaccharide (derivative of l-glucose).
Acceleration and deceleration factors on the hydrolysis reaction of 4,6-O-benzylidene acetal group
Maki, Yuta,Kajihara, Yasuhiro,Nomura, Kota,Okamoto, Ryo,Izumi, Masayuki,Mizutani, Yasuhisa
supporting information, p. 15849 - 15856 (2021/01/18)
The benzylidene acetal group is one of the most important protecting groups not only in carbohydrate chemistry but also in general organic chemistry. In the case of 4,6-O-benzylidene glycosides, we previously found that the stereochemistry at 4-position altered the reaction rate constant for hydrolysis of benzylidene acetal group. However, a detail of the acceleration or deceleration factor was still unclear. In this work, the hydrolysis reaction of benzylidene acetal group was analyzed using the Arrhenius and Eyring plot to obtain individual parameters for glucosides (Glc), mannosides (Man), and galactosides (Gal). The Arrhenius and Eyring plot indicated that the pre-exponential factor (A) and ΔS? were critical for the smallest reaction rate constant of Gal among nonacetylated substrates. On the other hand, both Ea/ΔH? and A/ΔS? were influential for the smallest reaction rate constant of Gal among diacetylated substrates. All parameters obtained suggested that the rate constant for hydrolysis reaction was regulated by protonation and hydration steps along with solvation. The obtained parameters support wide use of benzylidene acetal group as orthogonal protection of cis- and trans-fused bicyclic systems through the fast hydrolysis of the trans-fused benzylidene acetal group.
Both d - And l -Glucose Polyphosphates Mimic d - myo-Inositol 1,4,5-Trisphosphate: New Synthetic Agonists and Partial Agonists at the Ins(1,4,5)P3Receptor
Shipton, Megan L.,Riley, Andrew M.,Rossi, Ana M.,Brearley, Charles A.,Taylor, Colin W.,Potter, Barry V. L.
, p. 5442 - 5457 (2020/07/21)
Chiral sugar derivatives are potential cyclitol surrogates of the Ca2+-mobilizing intracellular messenger d-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P3]. Six novel polyphosphorylated analogues derived from both d- and l-glucose were synthesized. Binding to Ins(1,4,5)P3 receptors [Ins(1,4,5)P3R] and the ability to release Ca2+ from intracellular stores via type 1 Ins(1,4,5)P3Rs were investigated. β-d-Glucopyranosyl 1,3,4-tris-phosphate, with similar phosphate regiochemistry and stereochemistry to Ins(1,4,5)P3, and α-d-glucopyranosyl 1,3,4-tris-phosphate are full agonists, being equipotent and 23-fold less potent than Ins(1,4,5)P3, respectively, in Ca2+-release assays and similar to Ins(1,4,5)P3 and 15-fold weaker in binding assays. They can be viewed as truncated analogues of adenophostin A and refine understanding of structure-activity relationships for this Ins(1,4,5)P3R agonist. l-Glucose-derived ligands, methyl α-l-glucopyranoside 2,3,6-trisphosphate and methyl α-l-glucopyranoside 2,4,6-trisphosphate, are also active, while their corresponding d-enantiomers, methyl α-d-glucopyranoside 2,3,6-trisphosphate and methyl α-d-glucopyranoside 2,4,6-trisphosphate, are inactive. Interestingly, both l-glucose-derived ligands are partial agonists: they are among the least efficacious agonists of Ins(1,4,5)P3R yet identified, providing new leads for antagonist development.
