7208-47-1Relevant articles and documents
A novel low-molecular-mass pumpkin polysaccharide: Structural characterization, antioxidant activity, and hypoglycemic potential
Huang, Linlin,Li, Fei,Li, Quanhong,Liang, Li,Wei, Yunlu,Yu, Guoyong
, (2020/10/02)
The novel natural low-molecular-mass polysaccharide (SLWPP-3) from pumpkin (Cucurbia moschata) was separated from the waste supernatant after macromolecular polysaccharide production and purified using a DEAE cellulose-52 column and gel-filtration chromatography. Chemical and instrumental studies revealed that SLWPP-3 with a molecular mass of 3.5 kDa was composed of rhamnose, glucose, arabinose, galactose and uronic acid with a weight ratio of 1: 1: 4: 6: 15, and primarily contained →3,6)-β-D-Galp-(1→, →4)-α-GalpA-(1→(OMe), →4)-α-GalpA-(1→, →2,4)-α-D-Rhap-(1→, →3)-β-D-Galp-(1→, →4)-α-D-Glcp, and →4)-β-D-Galp residues in the backbone. The branch chain passes were connected to the main chain through the O-4 atom of glucose and O-3 atom of arabinose. Physiologically, the ability of SLWPP-3 to inhibit carbohydrate-digesting enzymes and DPPH and ABTS radicals, as well as protect pancreatic β cells from oxidative damage by decreasing MDA levels and increasing SOD activities, was confirmed. The findings elucidated the structural types of pumpkin polysaccharides and revealed a potential adjuvant natural product with hypoglycemic effects.
Structural features and antioxidant activity of a new galactoglucan from edible mushroom Pleurotus djamor
Maity, Gajendra Nath,Maity, Prasenjit,Khatua, Somanjana,Acharya, Krishnendu,Dalai, Sudipta,Mondal, Soumitra
, p. 743 - 749 (2020/12/07)
A new water soluble galactoglucan with apparent molecular weight ~1.61 × 105 Da, was isolated from the edible mushroom Pleurotus djamor by hot water extraction followed by purification through dialysis tubing cellulose membrane and sepharose 6B column chromatography. The sugar analysis showed the presence of glucose and galactose in a molar ratio of nearly 3:1 respectively. The structure of the repeating unit in the polysaccharide was determined through chemical and NMR experiments as:[Formula presented] In vitro antioxidant studies showed that the PDPS exhibited hydroxyl radical scavenging activity (EC50 = 1.681 ± 0.034 mg/mL), DPPH radical scavenging activity (EC50 = 3.83 ± 0.427 mg/mL), reducing power (EC50 = 4.258 ± 0.095 mg/mL), and ABTS radical quenching activity (EC50 = 0.816 ± 0.077 mg/mL). So, PDPS should be explored as a natural antioxidant.
Isolation, purification and structural characterization of a water-soluble polysaccharide HM41 from Halenia elliptica D. Don
Liu, Chun-Lan,Li, Yang,Xu, Gui-Yun,Li, Ya-Shuang
, p. 979 - 983 (2016/06/13)
A water-soluble polysaccharide, HM41, was obtained from Halenia elliptica D. Don by acidic ethanol fractionation and gel filtration. Its homogeneity was confirmed by chromatography using multiple systems. HM41 was composed of rhamnose (Rha), arabinose (Ara), xylose (Xyl), mannose (Man), galactose (Gal), glucose (Glc) with a molar ratio of 1.0:5.5:1.8:3.0:9.4:21. The average molecular weight of HM41 was approximately 1.17 × 104. Periodate oxidation, Smith degradation, methylation and GC, IR, NMR, XRD, GC-MS analysis were used for the structural analysis of HM41. Its main chain was composed mainly of β-(1 → 4)Gal, β-(1 → 4)Glc and β-(1 → 6)Glc. β-(1 → 4)Gal were substituted at 6-O and on average there were 14 branches among 23 main chain residues; (1 → 4)Glc had no branch; (1 → 6)Glc were substituted at 3-O and on average there were 9 branches among 14 main chain residues. The side chain was composed of (1 → 3,6)-Rha, (1 → 4)/(1 → 5)-Ara, (1 → 4)/(1 → 5)-Xyl, (1 → 4,6)-Man and (1 → 2)-Glc. The terminal residue was composed of Ara, Xyl, Man, Gal, and Glc. Then, we demonstrated that HM and HM41 had strong scavenging activities in vitro hydroxyl. Overall, HM and HM41 may have potential applications in the antioxidants for medical and food industry.
Acyl transfer reactions of carbohydrates, alcohols, phenols, thiols and thiophenols under green reaction conditions
Giri, Santosh Kumar,Kartha, K. P. Ravindranathan
, p. 11687 - 11696 (2015/02/19)
Acyl transfer reactions of various carbohydrates, alcohols, phenols, thiols and thiophenols were achieved at room temperature in high yields and catalytic efficiency in the presence of methane sulfonic acid, a green organic acid, under solvent-free conditions over short time periods. The method is mild enough to allow acid labile substituents such as isopropylidene acetals and trityl ethers on the reacting substrates to be left completely unaffected. Esterification of free mono- and dicarboxylic acids such as acetic acid, cinnamic acid, sialic acid and tartaric acid with alcohols such as menthol, ethanol, methanol or propylene glycol has also been achieved efficiently at room temperature. A comparative study of the method with the silica-sulfuric acid is also reported.
Cu(ClO4)2·6H2O catalyzed solvent free per-O-acetylation and sequential one-pot conversions of sugars to thioglycosides
Chatterjee, Debnath,Paul, Abhijit,Rajkamal,Yadav, Somnath
, p. 29669 - 29674 (2015/05/20)
The solvent free per-O-acetylation of various reducing and non-reducing sugars has been carried out using stoichiometric amounts of acetic anhydride and copper(ii) perchlorate hexahydrate as the catalyst. The reactions with various reducing monosaccharides have also been followed by a one-pot sequential conversion to the corresponding thioglycosides in high yields. This journal is
I2/ionic liquid as a highly efficient catalyst for per-O-acetylation of sugar under microwave irradiation
Xiong, Xingquan,Yi, Chao,Han, Qian,Shi, Lin,Li, Sizhong
, p. 237 - 243 (2015/09/28)
A practical and highly efficient approach was developed to synthesize peracetylated sugar derivatives using a recyclable iodine/PEG400-based ionic liquid catalyst (I2/IL). The peracetylated sugars were readily obtained in a few minutes in excellent yields (90%-99%, 13 examples) on a multi-gram scale (50.0 mmol) by the reaction of sugar and acetic anhydride under microwave irradiation in the absence of a volatile organic solvent. The desired product was easily obtained by simple extraction with toluene from the reaction mixture, and I2/ILs can be readily recovered and reused at least six times without obvious loss in the yield. When the scale of the per-O-acetylation reaction was increased to 50.0 mmol, the desired product was still obtained in 90% yield after five recycles.
Isolation and characterization of a hyperbranched proteoglycan from Ganoderma Lucidum for anti-diabetes
Pan, Deng,Wang, Linqiang,Chen, Congheng,Hu, Bingwen,Zhou, Ping
supporting information, p. 106 - 114 (2015/02/19)
Presently, an efficient protein tyrosine phosphatase 1B (PTP1B) inhibitor, named FYGL-n, was isolatedfrom Ganoderma Lucidum and characterized for its structure and bioactivity. Structure and chain con-formation of FYGL-n based on both chemical and spectroscopic analysis showed that FYGL-n was ahyperbranched heteropolysaccharide bonded with protein via both serine and threonine residues by O-type glycoside, and showed a sphere observed by AFM. Specifically, monosaccharide compositionindicated that FYGL-n consisted of D-arabinose, D-galactose, L-rhamnose and D-glucose in a mole ratio of 0.08:0.21:0.24:0.47, with a molecular mass of 72.9 kDa. The analysis of amino acids in FYGL-n indicatedthat there were 16 common amino acids, among which aspartic acid, glycine, serine, alanine, glutamicacid and threonine were the dominant components. Also it was demonstrated that FYGL-n could inhibitthe PTP1B activity on a competitive mechanism in vitro.
Characterization of the chemical diversity of glycosylated mycosporine-like amino acids in the terrestrial cyanobacterium Nostoc commune
Nazifi, Ehsan,Wada, Naoki,Asano, Tomoya,Nishiuchi, Takumi,Iwamuro, Yoshiaki,Chinaka, Satoshi,Matsugo, Seiichi,Sakamoto, Toshio
, p. 154 - 168 (2015/02/18)
Mycosporine-like amino acids (MAAs) are UV-absorbing pigments, and structurally unique glycosylated MAAs are found in the terrestrial cyanobacterium Nostoc commune. In this study, we examined two genotypes of N. commune colonies with different water extract UV-absorption spectra. We found structurally distinct MAAs in each genotype. The water extract from genotype A showed a UV-absorbing spectrum with an absorption maximum at 335 nm. The extract contained the following compounds: 7-O-(β-arabinopyranosyl)-porphyra-334 (478 Da), pentose-bound shinorine (464 Da), hexose-bound porphyra-334 (508 Da) and porphyra-334 (346 Da). The water extract from genotype B showed a characteristic UV-absorbing spectrum with double absorption maxima at 312 and 340 nm. The extract contained hybrid MAAs (1050 Da and 880 Da) with two distinct chromophores of 3-aminocyclohexen-1-one and 1,3-diaminocyclohexen linked to 2-O-(β-xylopyranosyl)-β-galactopyranoside. A novel 273-Da MAA with an absorption maximum at 310 nm was also identified in genotype B. The MAA consisted of a 3-aminocyclohexen-1-one linked to a γ-aminobutyric acid chain. These MAAs had potent radical scavenging activities in vitro and the results confirmed that the MAAs have multiple roles as a UV protectant and an antioxidant relevant to anhydrobiosis in N. commune. The two genotypes of N. commune exclusively produced their own characteristic glycosylated MAAs, which supports that MAA composition could be a chemotaxonomic marker for the classification of N. commune.
Tris(pentafluorophenyl)borane catalyzed acylation of alcohols, phenols, amines, and thiophenols under solvent-free condition
Prajapti, Santosh Kumar,Nagarsenkar, Atulya,Babu, Bathini Nagendra
, p. 1784 - 1787 (2014/03/21)
The acylation of alcohols, phenols, amines, and thiophenols was accomplished with 0.5 mol % of tris(pentafluorophenyl)borane [B(C 6F5)3] at ambient temperature under solvent-free condition. Major advantages of this method include high yield, short reaction time, simple procedure, compatibility with sensitive protecting groups as well as other functional groups, absence of racemization of optical active compounds, and epimerization of sugars.
Silica-supported boric acid catalyzed synthesis of dihydropyrimidin-2-ones, bis(indolyl)methanes, esters and amides
Kumar, Vishal,Singh, Chitra,Sharma, Upendra,Verma, Praveen K.,Singh, Bikram,Kumar, Neeraj
, p. 83 - 89 (2014/02/14)
Silica-supported boric acid (H3BO3-SiO2) has been established as a green, efficient and recyclable catalyst for the synthesis of dihydropyrimidin-2-ones, bis(indolyl)methanes, and acetylation of alcohols, phenols, amines and thiols under solvent free conditions. The main features of the present method include clean reaction, mild conditions, low loading of environment friendly catalyst and easy workup procedure. The catalyst can be recycled at least five times without any significant loss in activity.
