We report a universal straightforward strategy for the chemical synthesis of modified oligoribonucleotides containing functional groups of different structures at the 2′ position of ribose. The on-column synthetic concept is based on the incorp...
Bipyridine ethers are commonly occurring structural motifs in supramolecular chemistry. The herein reported efforts aim to extend the synthetic platform of bipyridino-precursors with new bifunctional intermediates and to improve some previously repor...
Benzhydryl protection of primary and secondary alcohols has been reported previously via reaction with metal alcoholates. Our aim was to find generally useful and very mild conditions for the alcoholic protection and deprotection of nucleosides with...
Chemical synthesis of 3-deoxy-d-manno-2-octulosonic acid (Kdo)-containing glycans, such as bacterial lipopolysaccharides (LPSs) and capsular polysaccharides (CPSs), is in high demand for the development of vaccines against pathogenic bacteria. We hav...
A novel metal-free organobase-catalyzed regioselective benzoylation of diols and carbohydrates has been developed. Treatment of diol and carbohydrate substrates with 1.1 equiv. of 1-benzoylimidazole and 0.2 equiv. of 1,8-diazabicyclo[5.4.0]undec-7-en...
This communication reports a novel synthesis route for the preparation of monofunctionalized β-cyclodextrin in a single stage. The approach involves only the in-situ protection of secondary hydroxyl groups as an excellent alternative to the classical...
New enantiomerically pure C16-alkyl diamides derived from trihydroxy cyclohexane-1,2-dicarboxylic acid have been synthesized from (−)-shikimic acid. The hydroxyl groups in these compounds are free or, alternatively, they present full or partial...
The regioselective protection of the 4-hydroxyl group of 3,4-dihydroxy-benzaldehyde was accomplished with seven different protecting groups (benzyl, p-methoxybenzyl, o-nitrobenzyl, 2,6-dichlorobenzyl, 3,4-dichlorobenzyl, vinyl and propargyl) in yield...
In this paper, a new and efficient synthesis of 6-O-methylscutellarein (3), the major metabolite of the natural medicine scutellarin, is reported. Two hydroxyl groups at C-4′ and C-7 in 2 were selectively protected by chloromethyl methyl ether after...
The encapsulation of active components is currently used as common methodology for the insertion of additional functions like self-healing properties on a polymeric matrix. Among the different approaches, polyurea microcapsules are used in different...
An efficient nickel-catalyzed removal of alkene protection group under mild condition with high functional group tolerance through chain walking process has been established. Not only phenolic ethers, but also alcoholic ethers can be tolerated with t...
Herein, a convergent, practicable and first total synthesis of the natural product, (±)-methyl salvianolate A, is reported. The key features of the approach are the use of a Horner–Wadsworth–Emmons reaction and the protection of mu...
Our study explores the antioxidant and cytoprotective effects of baicalein and further discusses the possible mechanisms. A methyl thiazolyl tetrazolium (MTT) assay revealed that baicalein could considerably enhance the viability of hydroxyl radical-...
Styrylquinolines are heterocyclic compounds that are known for their antifungal and antimicrobial activity. Metal complexation through hydroxyl groups has been claimed to be a plausible mechanism of action for these types of compounds. A series of no...
In this study, the antioxidant activities of 15 flavonoids against lard oil oxidation were determined by using the Rancimat test. Quercetin, dihydromyricetin, luteolin and kaempferol showed the strongest antioxidant activity, with protection factor v...
The 2-[(4-fluorophenyl)sulfonyl]ethoxy carbonyl (Fsec) group for protection of hydroxyl groups has been designed, synthesized, and evaluated. Fsec-Cl was readily prepared in 91% yield over three steps and subsequently used to protect 4-fluorobenzyl a...
Complete assignments of the 1H and 13C NMR chemical shifts for the monoterpenes, borneol 1a and isoborneol 2a, as well as their derivatives (1b–1g and 2b–2g), in which the secondary hydroxy group is protected with various protecting group...
A series of novel functional polycarbonates, specifically poly(solketal glycidyl ether carbonate-co-propylene carbonate)s with varying compositions, were synthesized through the ring-opening copolymerization of solketal glycidyl ether, propylene oxid...
The article presents the results of the synthesis and characteristics of the amphiphilic block terpolymers, built of a hydrophilic polyesteramine block, and hydrophobic blocks made of lactidyl and glycolidyl units. These terpolymers were obtained dur...
Soil organic matter (SOM), along with the rock weathering, originating from the residues of animals, plants and microorganisms involved in soil formation and evolution. The stability of SOM could directly produce an effect on carbon sequestration. To...
This review summarizes studies of protection against singlet oxygen and radical damage by carotenoids. The main focus is on how substitutions of the carotenoid molecules determine high antioxidant activities such as singlet oxygen quenching and radic...
Widely used in biomedical and bioanalytical applications, the detonation nanodiamonds (NDs) are generally considered to be biocompatible and non-toxic to a wide range of eukaryotic cells. Due to their high susceptibility to chemical modifications, su...
Wood fiber and its products are modified to increase fire and bio-resistance. The best results are achieved by using modifiers that enter into chemical interaction with the hydroxylated substrate, forming the organic matrix of the materials. The purp...
A feasibility and chemical study of the coupling conditions of L-ascorbic acidwith ferulic acid derivatives are described on the basis of the known synergistic effects ofmixtures of various antioxidants. Novel L-ascorbic ferulic hybrids linked at the...
A general scheme for the synthesis of C8-arylpurine phosphoramidites has been developed. C8-Arylation of C8-bromo-2′-deoxyguanosine is the key step and has been achieved through the use of a Suzuki coupling. Since the coupling reaction is conducted u...
It is of great significance to develop sustainable processes of catalytic reaction. We report a selective procedure for the synthesis of acetylated bioactive compounds in water. The use of 1-acetylimidazole combined with Er(OTf)3 as a Lewis acid cata...
In this study, we report on an orthogonal strategy for the precise synthesis of 3,3′-, 3,4′-, and 3,6′-phenylpropanoid sucrose esters (PSEs). The strategy relies on carefully selected protecting groups and deprotecting agents, takin...
The beneficial effects of polyphenols, predominantly in the context of oxidative stress-related diseases such as cancer, cardiovascular diseases and neurological conditions including Alzheimer’s and Parkinson’s diseases, have been documen...
In natural product synthesis, the procurement of easily accessible starting materials is crucial. Chromenones and their subclass, coumarins, are a wide family of small, oxygen-containing aromatic heterocycles. Phenylcoumarins offer a particularly exc...
Recently, considerable attention has been devoted to heterogeneous catalysts. Generally, heterogeneous catalysts offer several advantages, such as mild reaction conditions, high throughput, and ease of work-up procedures. Among the heterogeneous cata...
Given the recent research on the application of eco-sustainable methods in organic chemistry, we have focused our attention on the derivatization processes for fundamental functional groups in organic chemistry, such as amino, hydroxyl and carbonyl g...
Methylglyoxal-induced oxidative stress and cytotoxicity are the main factors causing neuronal death-related, diabetically induced memory impairment. Antioxidant and anti-apoptotic therapy are potential intervention strategies. In this study, 25 flavo...
Sulfur-containing monosaccharide derivatives can be highly valuable for obtaining compounds with biological activities. In this work, a synthetic route starting from D-mannose has been designed. After a convenient hydroxyl protection and anomeric car...
Poly(ether ether ketone) dendrimers and hyperbranched polymers were prepared from 3,5-dimethoxy-4′-(4-fluorobenzoyl)diphenyl ether and 3,5-dihydroxy-4′-(4-fluorobenzoyl)diphenyl ether through aromatic nucleophilic substitution reactions. 1-(tert-Buty...
Acetalization and deacetalation are a pair of routine manipulations to protect and deprotect the 4- and 6-hydroxyl groups of glycosides in the synthesis of glycosyl building blocks. In this study, we found that treatment of SnCl4 with various carbohy...
An electroactive polytriphenylamine (PTPA-C6) is blended with poly(styrene-co-hydroxystyrene) (PS-co-PHS) as coating layers to enhance protection efficiency of PTPA-C6 on iron substrate in 3.5% sodium chloride (NaCl) solution. Experimental results sh...
Accumulative evidence indicated that the pathologically accumulated metal ions (iron species and Mn3+) and abnormally up-regulated monoamine oxidase B (MAOB) activity induced oxidation of endogenous dopamine (DA) can lead to mitochondria impairment,...
Synthesis of 5''-phosphate 2'-O-ribosylribonucleosides [Nr(p)] of four common ribonucleosides, and 3'-phosphoramidites of 5''-phosphate 2'-O-ribosyladenosine and 2'-O-ribosylguanosine using the H-phosphonate chemistry is described. An additional rin...
In order to prepare functional materials for antioxidant and ultraviolet (UV)-protective green food packaging, condensed tannin, previously extracted from larch bark, was mixed with polyvinyl alcohol (PVA), and then the mixture was used to cast compo...
Disaccharide nucleosides are an important class of natural compounds that have a variety of biological activities. In this study, we report on the synthesis of disaccharide nucleosides utilizing the temporary protection of the 2′,3′-cis-diol of ribon...
Herein, silicon-protected, ortho-methylated hydroxy-pyridines were reported as initiators in 2-aminoalkoxy-bis(phenolate)yttrium complexes for rare earth metal-mediated group-transfer polymerization (REM-GTP) of Michael-type monomers. To introduce th...
High-performance coating could be used to protect steels in engineering. The GPTMS-TEOS hybrid coatings were successfully prepared using (3-glycidoxypropyl) trimethoxysilane (GPTMS) and tetraethylorthosilicate (TEOS) as reaction raw materials and die...
25 September 2013
The aim of this study was to evaluate the in cellulo inhibition of hydrogen-peroxide-induced oxidative stress in skin fibroblasts using different low-molecular-weight polysaccharides (LMPS) prepared from agar (LMAG), chitosan (LMCH) and starch (LMS...
A series of lipoamino acids were synthesized and their neuroprotective effect against brain ischemia induced by oxygen-glucose deprivation (OGD) on rat cerebral slices was evaluated. Among these compounds, N-stearoyl-L-tyrosine (4), N-stearoyl-L-seri...
Synthesis of the title compound,1-(2'-deoxy-b-D-ribofuranosyl)-1H-imidazo[4,5-d]pyridazine-4,7(5H,6H)-dione (1), is reported. It was synthesized in five steps, commencing with methyl 1-(b-D-ribofuranosyl)imidazo-4,5-dicarboxylate (2). The 3',5'-hydro...
In this work, we present the fabrication of highly luminescent carbon dots (CDs) by a double passivation method with the assistance of Ca(OH)2. In the reaction process, Ca2+ protects the active functional groups from overconsumption during dehydratio...
Silicone resins are widely applied as coating materials due to their unique properties, especially those related to very good heat resistance. The most important effect on the long-term heat resistance of the coating is connected with the type of res...
By exploiting the regioselective protection of the hydroxyl groups of silibinin along with the well-known phosphoramidite chemistry, we have developed an efficient strategy for the synthesis of new silibinin-modified species, which we have named Phos...
Chronic neurodegenerative diseases are typically associated with oxidative stress conditions leading to neuronal cell death. We aimed to investigate the neuroprotective effect of three pyranocoumarins (decursin, decursinol angelate, and decursinol) t...
As a small-molecule reductant substance, hydrogen gas has an obvious antioxidant function. It can selectively neutralize hydroxyl radicals (•OH) and peroxynitrite (ONOO•) in cells, reducing oxidative stress damage. The purpose of this study...
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