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Wei-Syun Song, Si-Xian Liu, Che-Chien Chang
The preparation of 2-deoxy-l-ribose derivatives or mirror image deoxyribonucleosides (l-deoxyribonucleosides) from d-ribose is reported. Starting from inexpensive d-ribose, an acyclic d-form carbohydrate precursor was synthesized to study a unique carbonyl translocation process. In this novel radical reaction, not only was the configuration of the sugar transformed from the d-form to the l-form, but also deoxygenation at the C(2) position of the sugar was successfully achieved. This is one of the most practical methods for converting a d-sugar to a 2-deoxy-l-sugar in a one-step reaction...
November 29, 2018: Journal of Organic Chemistry
Ya-Nan Wang, Yan-Hua Mou, Yu Dong, Yan Wu, Bing-Yu Liu, Jian Bai, Dao-Jiang Yan, Le Zhang, Dan-Qing Feng, Yue-Hu Pei, You-Cai Hu
Six new diphenyl ethers ( 1 ⁻ 6 ) along with eleven known analogs were isolated from the ethyl acetate extract of a marine-derived Aspergillus sydowii guided by LC-UV-MS. Their structures were unambiguously characterized by HRESIMS, NMR, as well as chemical derivatization. Compounds 1 and 2 are rare diphenyl ether glycosides containing d-ribose. The absolute configuration of the sugar moieties in compounds 1 ⁻ 3 was determined by a LC-MS method. All the compounds were evaluated for their cytotoxicities against eight cancer cell lines, including 4T1, U937, PC3, HL-60, HT-29, A549, NCI-H460, and K562, and compounds 1 , 5 , 6 , and 8 ⁻ 11 were found to exhibit selective cytotoxicity against different cancer cell lines...
November 16, 2018: Marine Drugs
Zeba Siddiqui, Mohammad Faisal, Abdulrahman A Alatar, Saheem Ahmad
Non-enzymatic glycation occurs rapidly which ultimately leads to the formation of advanced glycation endproducts (AGEs). These AGEs have shown to associated with the development of many diseases such as diabetes-mellitus. This study is focused on immunological characterization of glycated-Hb induced by d-ribose. Here, we analysed the immunogenicity of glycated-Hb by direct binding and competitive inhibition ELISA. Direct binding ELISA confirmed that glycated-Hb was highly immunogenic and induced high titre antibodies as compared to native-Hb...
November 13, 2018: International Journal of Biological Macromolecules
Chong Liu, Qi Chen, Steven Cardinale, Terry L Bowlin, Stewart W Schneller
A convenient stereospecific synthesis of 6'-fluoro-3-deazaneplanocin (6) has been accomplished from d-ribose in 15 steps. It is reported to possess significant activity towards Ebola (Zaire, Vero, μM: EC50  < 0.36; CC50 125; SI > 347) with moderate inhibition of the target enzyme (S-adenosylhomocysteine hydrolase), which did not correlate directly with its anti-Ebola effects. Compound 6, with limited cytotoxicity, also displayed activity against measles, H1N1 and Pichinde.
October 22, 2018: Bioorganic & Medicinal Chemistry Letters
Keisuke Hirata, Takashi Uchida, Yoshikata Nakajima, Toru Maekawa, Toru Mizuki
Rare sugars are defined as monosaccharides and their derivatives, which rarely exist in nature and have various beneficial effects on organisms, biomaterials and foods. Glycolipids are composed of sugars and lipids and have been intensively studied in various fields such as environmental engineering, nanotechnology and molecular biology. Here, we synthesise new types of glycolipids composed of rare sugars, glycerol and lipids (RSGLs), using 6 different types of rare sugars by combining the modified Fischer and lipase reverse reactions...
October 2018: Heliyon
Sangmi Oh, Yumi Park, Curtis A Engelhart, Joshua B Wallach, Dirk Schnappinger, Kriti Arora, Michelle Manikkam, Brian Gac, Hongwu Wang, Nicholas Murgolo, David B Olsen, Michael Goodwin, Michelle Sutphin, Danielle M Weiner, Laura E Via, Helena I M Boshoff, Clifton E Barry
Magnesium plays an important role in infection with Mycobacterium tuberculosis ( Mtb) as a signal of the extracellular environment, as a cofactor for many enzymes, and as a structural element in important macromolecules. Raltegravir, an antiretroviral drug that inhibits HIV-1 integrase is known to derive its potency from selective sequestration of active-site magnesium ions in addition to binding to a hydrophobic pocket. In order to determine if essential Mtb-related phosphoryl transfers could be disrupted in a similar manner, a directed screen of known molecules with integrase inhibitor-like pharmacophores ( N-alkyl-5-hydroxypyrimidinone carboxamides) was performed...
November 21, 2018: Journal of Medicinal Chemistry
João Paulo Bizarro Lopes, Luana Silva, Gabriela da Costa Franarin, Marco Antonio Ceschi, Diogo Seibert Lüdtke, Rafael Ferreira Dantas, Cristiane Martins Cardoso de Salles, Floriano Paes Silva-Jr, Mario Roberto Senger, Isabella Alvim Guedes, Laurent Emmanuel Dardenne
A series of hybrids containing tacrine linked to carbohydrate-based moieties, such as d-xylose, d-ribose, and d-galactose derivatives, were synthesized by the nucleophilic substitution between 9-aminoalkylamino-1,2,3,4-tetrahydroacridines and the corresponding sugar-based tosylates. All compounds were found to be potent inhibitors of both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) in the nanomolar IC50 scale. Most of the d-xylose derivatives (6a-e) were selective for AChE and the compound 6e (IC50  = 2...
October 9, 2018: Bioorganic & Medicinal Chemistry
Joanna M Watt, Mark P Thomas, Barry V L Potter
Cyclic adenosine 5'-diphosphate ribose (cADPR) is an emerging Ca2+ -mobilising second messenger. cADPR analogues have been generated as chemical biology tools via both chemo-enzymatic and total synthetic routes. Both routes rely on the cyclisation of a linear precursor to close an 18-membered macrocyclic ring. We show here that, after cyclisation, there are two possible macrocyclic product conformers that may be formed, depending on whether cyclisation occurs to the "right" or the "left" of the adenine base (as viewed along the H-8 → C-8 base axis)...
October 15, 2018: Scientific Reports
Yi Li, Mohd Shahnawaz Khan, Firoz Akhter, Fohad Mabood Husain, Saheem Ahmad, Lihui Chen
Advanced glycation end-products (AGEs) can aggregate amid incessant inflammation, as may be available in patients with rheumatoid arthritis. d-Ribose reacts more promptly than glucose monosaccharide to the proteins and forms heterogeneous group of products known as AGEs. Obesity includes persons with provocative joint inflammation with increased lipid profile. Immunogenic evidences recommend a cross-sectional relationship between glycated LDL-Apo B100 and inflammation. The point of this examination was to look at the connection between d-ribose glycated ApoB100 (ApoB100-AGE) with obesity and rheumatoid arthritis...
October 9, 2018: International Journal of Biological Macromolecules
Vladimir E Oslovsky, Mikhail S Drenichev, Cyril S Alexeev, Pavel N Solyev, Roman S Esipov, Sergey N Mikhailov
This unit describes an effective method for the preparation of natural cytokinins and their synthetic derivatives based on enzymatic cleavage of the N-glycosidic bond of N6 -substituted adenosine or O6 -substituted inosine derivatives in the presence of purine nucleoside phosphorylase (PNP) and Na2 HAsO4 . The arsenolysis reaction is irreversible due to the hydrolysis of the resulting α-D-ribose-1-arsenate. As a result, the desired products are formed in near-quantitative yields, as indicated by high-performance liquid chromatography (HPLC) analysis, and can easily be isolated...
October 9, 2018: Current Protocols in Nucleic Acid Chemistry
Meera Haridas, Eman M M Abdelraheem, Ulf Hanefeld
2-Deoxy-D-ribose-5-phosphate aldolase (DERA) is a class I aldolase that offers access to several building blocks for organic synthesis. It catalyzes the stereoselective C-C bond formation between acetaldehyde and numerous other aldehydes. However, the practical application of DERA as a biocatalyst is limited by its poor tolerance towards industrially relevant concentrations of aldehydes, in particular acetaldehyde. Therefore, the development of proper experimental conditions, including protein engineering and/or immobilization on appropriate supports, is required...
October 3, 2018: Applied Microbiology and Biotechnology
Dan Zeng, Can Hu, Ru-Liu Li, Chuan-Quan Lin, Jia-Zhong Cai, Ting-Ting Wu, Jing-Jing Sui, Wen-Biao Lu, Wei-Wen Chen
Astragalus membranaceus (Radix Astragali, RA) and Atractylodes macrocephala (Rhizoma Atractylodis Macrocephalae, RAM) are often used to treat gastrointestinal diseases. In the present study, we determined the effects of polysaccharides extracts from these two herbs on IEC-6 cell migration and explored the potential underlying mechanisms. A migration model with IEC-6 cells was induced using a single-edged razor blade along the diameter of cell layers in six-well polystyrene plates. The cells were grown in control media or media containing spermidine (5 μmol·L-1 , SPD), alpha-difluoromethylornithine (2...
September 2018: Chinese Journal of Natural Medicines
Heithem Ben Amara, Hyun Y Song, Eunju Ryu, Ji S Park, Frank Schwarz, Byeong M Kim, Bong-Kyu Choi, Ki-Tae Koo
This study aimed to verify, in in vivo settings, whether quorum-sensing inhibition molecules could attenuate alveolar bone loss induced by Porphyromonas gingivalis/Fusobacterium nucleatum co-infection and reduce the bacterial colonization of periodontal tissues. In BALB/c mice, periodontitis was induced through oral inoculation with P. gingivalis and F. nucleatum six times during a 42-d period. Quorum sensing inhibitors (a furanone compound and D-ribose) were administered simultaneously with bacterial infection...
September 19, 2018: European Journal of Oral Sciences
Adrian Richter, Ines Rudolph, Ute Möllmann, Kerstin Voigt, Chun-Wa Chung, Onkar M P Singh, Michael Rees, Alfonso Mendoza-Losana, Robert Bates, Lluís Ballell, Sarah Batt, Natacha Veerapen, Klaus Fütterer, Gurdyal Besra, Peter Imming, Argyrides Argyrou
Nitro-substituted 1,3-benzothiazinones (nitro-BTZs) are mechanism-based covalent inhibitors of Mycobacterium tuberculosis decaprenylphosphoryl-β-D-ribose-2'-oxidase (DprE1) with strong antimycobacterial properties. We prepared a number of oxidized and reduced forms of nitro-BTZs to probe the mechanism of inactivation of the enzyme and to identify opportunities for further chemistry. The kinetics of inactivation of DprE1 was examined using an enzymatic assay that monitored reaction progress up to 100 min, permitting compound ranking according to kinact /Ki values...
September 7, 2018: Scientific Reports
Sang Eun Jeong, Byung Hee Chun, Kyung Hyun Kim, Dongbin Park, Seong Woon Roh, Se Hee Lee, Che Ok Jeon
The genomic and metabolic features of Weissella koreensis, one of the major lactic acid bacteria in kimchi, were investigated through genomic, metabolic, and transcriptomic analyses for the genomes of strains KCTC 3621T , KACC 15510, and WiKim0080. W. koreensis strains were intrinsically vancomycin-resistant and harbored potential hemolysin genes that were actively transcribed although no hemolysin activity was detected. KEGG and reconstructed fermentative metabolic pathways displayed that W. koreensis strains commonly employ the heterolactic pathway to produce d-lactate, ethanol, acetate, CO2 , d-sorbitol, thiamine, and folate from various carbohydrates including d-glucose, d-mannose, d-lactose, l-malate, d-xylose, l-arabinose, d-ribose, N-acetyl-glucosamine, and gluconate, and strains KCTC 3621T and WiKim0080 additionally have metabolic pathways of d-galacturonate and d-glucoronate...
December 2018: Food Microbiology
Abraham A A Osinubi, Leke Jacob Medubi, Edidiong N Akang, Lawal K Sodiq, Titilola A Samuel, Taiwo Kusemiju, James Osolu, Danladi Madu, Olufemi Fasanmade
Over 18% of pregnant women are affected by diabetes mellitus (DM) and Insulin has been the commonest drug used in its treatment. There are reports of noncompliance to insulin due to trypanophobia, with suggestions for the use of oral hypoglycaemic agents (OHAs). However, the opposing views about the benefits and risk of oral hypoglycaemic agents (OHAs) warrant a continuous search for an alternative regimen. Therefore, this study is aimed at comparing the antidiabetic effects of d-ribose-l-cysteine (riboceine) with vildagliptin, glibenclamide, metformin, glipizide and insulin in diabetes in pregnancy...
2018: Toxicology Reports
Yunfeng Cheng, Jinghang Xie, Kyung-Hyun Lee, Rajiv L Gaur, Aiguo Song, Tingting Dai, Hongjun Ren, Jiannan Wu, Zhaogang Sun, Niaz Banaei, Demir Akin, Jianghong Rao
Tuberculosis (TB) remains a public health crisis and a leading cause of infection-related death globally. Although in high demand, imaging technologies that enable rapid, specific, and nongenetic labeling of live Mycobacterium tuberculosis (Mtb) remain underdeveloped. We report a dual-targeting strategy to develop a small molecular probe (CDG-DNB3) that can fluorescently label single bacilli within 1 hour. CDG-DNB3 fluoresces upon activation of the β-lactamase BlaC, a hydrolase naturally expressed in Mtb, and the fluorescent product is retained through covalent modification of the Mtb essential enzyme decaprenylphosphoryl-β-d-ribose 2'-epimerase (DprE1)...
August 15, 2018: Science Translational Medicine
Julien A Delbrouck, Abdellatif Tikad, Stéphane P Vincent
An efficient and regioselective approach for the construction of synthetically important γ-lactone glycosides is reported from unprotected aldoses through a new debenzylative lactonization (DBL) reaction. The scope and limitations of this DBL reaction are described starting from a series of commercially available hexoses (l-fucose, d-galactose, d-glucose) and pentoses (d-arabinose, d-ribose, d-lyxose, d-xylose) to afford the corresponding γ-lactones in good yields and without concomitant δ-lactone formation...
August 28, 2018: Chemical Communications: Chem Comm
Andrea Pérez-Villa, A Marco Saitta, Thomas Georgelin, Jean-François Lambert, François Guyot, Marie-Christine Maurel, Fabio Pietrucci
Understanding the mechanism of spontaneous formation of ribonucleotides under realistic prebiotic conditions is a key open issue of origins-of-life research. In cells, de novo and salvage nucleotide enzymatic synthesis combines 5-phospho-α-d-ribose-1-diphosphate (α-PRPP) and nucleobases. Interestingly, these reactants are also known as prebiotically plausible compounds. Combining ab initio molecular dynamics simulations with recently developed reaction exploration and enhanced sampling methods, we show that nucleobases and α-PRPP should spontaneously combine, under mild hydrothermal conditions, with an exothermic reaction and a facile mechanism, forming both purine and pyrimidine ribonucleotides...
September 6, 2018: Journal of Physical Chemistry Letters
Renaud Zelli, Waël Zeinyeh, Jean-Luc Décout
A one-pot glycosylation and cyclization procedure is described for the synthesis of 6-chloropurine ribonucleosides from chloropyrimidines. From such a procedure and modification of the obtained chloropurine ribonucleosides, many drug candidates or molecular tools for biological study designed from their similarity to naturally occurring nucleosides could be obtained. The synthesis begins by preparation of several amidinoaminochloropyrimidines as precursors for the one-pot procedure. Then, by adding trimethylsilyl trifluoromethanesulfonate (TMSOTf) to a mixture of a pyrimidine and 1-O-acetyl-2,3,5-tri-O-benzoyl-β-D-ribose, different 6-chloropurine ribonucleosides are obtained...
September 2018: Current Protocols in Nucleic Acid Chemistry
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