69,334 results match your criteria synthesis substituted

Vacancy-triggered and dopant-assisted NO electrocatalytic reduction over MoS.

Phys Chem Chem Phys 2021 Sep 15;23(35):19872-19883. Epub 2021 Sep 15.

Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an 710054, China.

Nitric oxide electroreduction reaction (NOER) is an efficient method for NH synthesis and NO-related pollutant treatment. However, current research on NOER catalysts mainly focuses on noble metals and single atom catalysts, while low-cost transition metal dichalcogenides (TMDCs) are rarely considered. Herein, by applying density functional theory (DFT) calculations, we study the catalytic performance of NOER over 2H-MoS monolayers with the most common S vacancies and some Mo atoms substituted by transition metal atoms (denoted as [email protected]). Read More

View Article and Full-Text PDF
September 2021

Nucleophile-nucleofuge duality of azide and arylthiolate groups in the synthesis of quinazoline and tetrazoloquinazoline derivatives.

Org Biomol Chem 2021 Sep 15;19(35):7706-7723. Epub 2021 Sep 15.

Institute of Technology of Organic Chemistry, Faculty of Materials Science and Applied Chemistry, Riga Technical University, Paula Valdena Str. 3, Riga, LV-1048, Latvia.

5-Arylthio-tetrazolo[1,5-]quinazolines (tautomers of 2-arylthio-4-azido-quinazolines) undergo facile nucleophilic aromatic substitution reactions with amines, alcohols and alkylthiols. This, combined with the recently reported arylsulfanyl group dance, provides straightforward access to 4-azido-2--, -, -substituted quinazolines and/or their tetrazolo tautomers from commercially available 2,4-dichloroquinazoline. The azidoazomethine-tetrazole tautomeric equilibrium and the electron-withdrawing character of the fused tetrazolo system plays a central role in the developed transformations. Read More

View Article and Full-Text PDF
September 2021

Visible-Light-Induced Transition-Metal-Free Nitrogen-Centered Radical Strategy for the Synthesis of 2-Acylated 9-Pyrrolo[1,2-]indoles.

J Org Chem 2021 Sep 15. Epub 2021 Sep 15.

Department of Chemistry and Chemical Engineering, Hunan Institute of Science and Technology, Yueyang 414006, China.

A convenient and efficient visible-light-induced tandem acylation/cyclization of -propargylindoles with aryl- or alkyl-substituted acyl oxime esters for the synthesis of 2-acyl-substituted 9-pyrrolo[1,2-]indoles under transition-metal-free conditions, which proceeds nitrogen-centered radical-mediated cleavage of the C-C σ-bond in acyl oxime esters, is established. The aryl or alkyl acyl radicals, which come from acyl oxime esters, attack the C-C triple bonds in -propargylindoles and then go through intramolecular cyclization/isomerization. Read More

View Article and Full-Text PDF
September 2021

Synthesis of a carborane-substituted bis(phosphanido) cobaltate(i), ligand substitution, and unusual P fragmentation.

Chem Sci 2021 Aug 7;12(33):11225-11235. Epub 2021 Jul 7.

Institute of Inorganic Chemistry, Universität Regensburg 93040 Regensburg Germany

Oxidative addition of the P-P single bond of an -carborane-derived 1,2-diphosphetane (1,2-C(PMes)BH) (Mes = 2,4,6-MeCH) to cobalt(-i) and nickel(0) sources affords the first heteroleptic complexes of a carborane-bridged bis(phosphanido) ligand. The complexes also incorporate labile ligands suitable for further functionalisation. Thus, the cobalt(i) complex [K([18]crown-6)][Co{1,2-(PMes)CBH}(cod)] (cod = 1,5-cyclooctadiene) bearing a labile cyclooctadiene ligand undergoes facile ligand exchange reactions with isonitriles and -butyl phosphaalkyne with retention of the bis(phosphanido) ligand. Read More

View Article and Full-Text PDF

Asymmetric synthesis of pharmaceutically relevant 1-aryl-2-heteroaryl- and 1,2-diheteroarylcyclopropane-1-carboxylates.

Chem Sci 2021 Aug 27;12(33):11181-11190. Epub 2021 Jul 27.

Department of Chemistry, Emory University 1515 Dickey Drive Atlanta GA 30322 USA

This study describes general methods for the enantioselective syntheses of pharmaceutically relevant 1-aryl-2-heteroaryl- and 1,2-diheteroarylcyclopropane-1-carboxylates through dirhodium tetracarboxylate-catalysed asymmetric cyclopropanation of vinyl heterocycles with aryl- or heteroaryldiazoacetates. The reactions are highly diastereoselective and high asymmetric induction could be achieved using either ()-pantolactone as a chiral auxiliary or chiral dirhodium tetracarboxylate catalysts. For - or -substituted aryl- or heteroaryldiazoacetates the optimum catalyst was Rh(-Ph-TPCP). Read More

View Article and Full-Text PDF

Design, synthesis, and bio-evaluation of new isoindoline-1,3-dione derivatives as possible inhibitors of acetylcholinesterase.

Res Pharm Sci 2021 Oct 19;16(5):482-492. Epub 2021 Aug 19.

Department of Animal Biotechnology, Cell Science Research Center, Royan Institute for Biotechnology, ACECR, Isfahan, I.R. Iran.

Background And Purpose: Alzheimer's disease is considered one of the lead causes of elderly death around the world. A significant decrease in acetylcholine level in the brain is common in most patients with Alzheimer's disease, therefore acetylcholinesterase (AChE) inhibitors such as donepezil and rivastigmine are widely used for patients with limited therapeutic results and major side effects.

Experimental Approach: A series of isoindoline-1,3-dione -N-benzyl pyridinium hybrids were designed, synthesized and evaluated as anti-Alzheimer agents with cholinesterase inhibitory activities. Read More

View Article and Full-Text PDF
October 2021

Methyl linked pyrazoles: Synthetic and Medicinal Perspective.

Mini Rev Med Chem 2021 Sep 14. Epub 2021 Sep 14.

Department of Chemistry, Central University of Haryana, Mahendergarh 123031, Haryana. India.

Pyrazoles, an important and well known class of the azole family, have been found to show a large number of applications in various fields specially of medicinal chemistry. Among pyrazole derivatives, particularly, methyl substituted pyrazoles have been reported as the potent medicinal scaffolds that exhibit a wide spectrum of biological activities. The present review is an attempt to highlight the detailed synthetic approaches for methyl substituted pyrazoles along with in depth analysis of their respective medical significances till March2021. Read More

View Article and Full-Text PDF
September 2021

Lewis Superacidic Catecholato Phosphonium Ions: Phosphorus-Ligand Cooperative C-H Bond Activation.

J Am Chem Soc 2021 Sep 15. Epub 2021 Sep 15.

Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, Heidelberg 69120, Germany.

A series of catecholato phosphonium ions, including the first stable bis(catecholato)-substituted derivatives, are isolated and fully characterized. The cations rank among the most potent literature-known Lewis acids on the Gutmann-Beckett and ion affinity scales. In contrast to halogenated or multiply charged phosphorus cations, Lewis superacidity is imparted by structural constraints, as disclosed by energy decomposition analysis. Read More

View Article and Full-Text PDF
September 2021

Halogen-bridged Methylnaphthyl Palladium Dimers as Versatile Catalyst Precursors in Coupling Reactions.

Angew Chem Int Ed Engl 2021 Sep 14. Epub 2021 Sep 14.

Umicore, PMC, Rodenbacher Chaussee 4, 63457, Hanau, GERMANY.

Halogen-bridged methylnaphthyl (MeNAP) palladium dimers are presented as multipurpose Pd-precursors, ideally suited for catalytic method development and preparative organic synthesis. By simply mixing with phosphine or carbene ligands, they are in situ converted into well-defined monoligated complexes. Their catalytic performance was benchmarked against state-of-the-art systems in challenging Buchwald-Hartwig, Heck, Suzuki and Negishi couplings, and ketone arylations. Read More

View Article and Full-Text PDF
September 2021

Chemoenzymatic Asymmetric Synthesis of Pyridine-based α-Fluorinated Secondary Alcohols.

Chembiochem 2021 Sep 14. Epub 2021 Sep 14.

University of Rostock: Universitat Rostock, Institute of Chemistry, A.-Einstein-Str. 3A, 18059, Rostock, GERMANY.

Fluoro-substituted and heteroaromatic compounds are valuable intermediates for a variety of applications in pharma- and agrochemistry and synthetic chemistry. This study investigates the chemoenzymatic preparation of chiral alcohols bearing a heteroaromatic ring with an increasing degree of fluorination in α-position. Starting from readily available picoline derivatives prochiral α-halogenated acyl moieties were introduced with excellent selectivity and 64-95% yield. Read More

View Article and Full-Text PDF
September 2021

A TEMPO-Functionalized Ordered Mesoporous Polymer as A Highly Active and Reusable Organocatalyst.

Chem Asian J 2021 Sep 14. Epub 2021 Sep 14.

Lanzhou University, College of Chemistry and Chemical Engineering, Lanzhou, CHINA.

The properties of high stability, periodic porosity, and tunable nature of ordered mesoporous polymers make these materials ideal catalytic nanoreactors. However, the application of them in organocatalysis have been rarely explored. We report herein for the first time the incorporation of a versatile organocatalyst, 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), into the pores of an FDU-type mesoporous polymer via pore surface engineering strategy. Read More

View Article and Full-Text PDF
September 2021

Cu(OTf) catalyzed Ugi-type reaction of ,-acetals with isocyanides for the synthesis of pyrrolidinyl and piperidinyl 2-carboxamides.

Chem Commun (Camb) 2021 Sep 14;57(73):9248-9251. Epub 2021 Sep 14.

Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, China.

The Cu(OTf) catalyzed Ugi-type reactions of ,-acetals with isocyanides have been described for the synthesis of pyrrolidinyl and piperidinyl 2-carboxamides. 4-Hydroxy-5-substituted-prolinamides can be obtained in high diastereoselectivities (2,4-/ > 19 : 1) and a stereoselective model was proposed for 2,4- selectivity. Moreover, 4-F-VH 032, a novel analog of the VHL ligand, was conveniently obtained by utilizing the present method. Read More

View Article and Full-Text PDF
September 2021

Green synthesis of carbamates and amides via [email protected] catalyzed C-O and C-N oxidative coupling accelerated by microwave irradiation.

Sci Rep 2021 Sep 13;11(1):18105. Epub 2021 Sep 13.

Research Laboratory of Green Organic Synthesis and Polymers, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Islamic Republic of Iran.

A new nano-scale [email protected] ([email protected]) was synthesized through a green, eco-friendly and cost-effective technique. The prepared catalyst was characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDXS), and inductively coupled plasma (ICP) analysis. The synthesized [email protected] catalyst indicated its performance in the C-O and C-N oxidative coupling using the reaction of 1,3-dicarbonyl derivatives/2- substituted phenols with amides for the preparation of carbamates, as well as in the reaction of aldehydes and various amines in the synthesis of amides. Read More

View Article and Full-Text PDF
September 2021

Synthesis and Spectroscopic Properties of 1,2,3-Triazole BOPAHY Dyes and Their Water-Soluble Triazolium Salts.

J Org Chem 2021 Sep 13. Epub 2021 Sep 13.

Molecular Design and Synthesis, Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium.

Water-soluble BOPAHY fluorophores have not yet been reported. The potential of 1,2,3-triazolium salts for the formation of water-soluble chromophores is explored. 1,2,3-Triazole-substituted pyrroles were synthesized in a metal-free pathway and alkylated to obtain water-soluble 1,2,3-triazolium BOPAHY dyes. Read More

View Article and Full-Text PDF
September 2021

Rare-Earth-Modified Titania Nanoparticles: Molecular Insight into Synthesis and Photochemical Properties.

Inorg Chem 2021 Sep 13. Epub 2021 Sep 13.

Department of Molecular Sciences, Swedish University of Agricultural Sciences, Box 7015, Uppsala SE-75007, Sweden.

A molecular precursor approach to titania (anatase) nanopowders modified with different amounts of rare-earth elements (REEs: Eu, Sm, and Y) was developed using the interaction of REE nitrates with titanium alkoxides by a two-step solvothermal-combustion method. The nature of an emerging intermetallic intermediate was revealed unexpectedly for the applied conditions via a single-crystal study of the isolated bimetallic isopropoxide nitrate complex [TiY(PrO)(NO)], a nonoxo-substituted compound. Powders of the final reaction products were characterized by powder X-ray diffraction, scanning electron microscopy-energy-dispersive spectroscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, Raman spectroscopy, and photoluminescence (PL). Read More

View Article and Full-Text PDF
September 2021

Recent Advancement in the One-Pot Synthesis of the Tri-Substituted Methanes (TRSMs) and Their Biological Applications.

Curr Org Synth 2021 Sep 9. Epub 2021 Sep 9.

Department of chemistry, University Institute of sciences, Chandigarh University, Ludhiana Highway, Mohali, Punjab . India.

The history of tri-substituted methanes (TRSMs) in chemical industries is much older. Tri-substituted methanes were previously used as dyes in the chemical industries. Still, there is a significant surge in researchers' interest in them due to their wide range of bioactivities. Read More

View Article and Full-Text PDF
September 2021

Synthesis of blue light emitting heterocycles cyclization of 2-pyridine derived 4-azido-r1,2,3-triazoles.

Org Biomol Chem 2021 Sep 13. Epub 2021 Sep 13.

M.V. Lomonosov Moscow State University, Russian Federation.

An efficient synthesis of 2-pyridine derived 4-azido-1,2,3-triazoles was elaborated using the corresponding dichlorodiazadienes as precursors. The reaction of the prepared 2-azine substituted diazadienes with sodium azide permits the preparation of target triazoles isolated in up to 92% yield. Subsequent thermal cyclization was studied. Read More

View Article and Full-Text PDF
September 2021

-Diastereoselective Synthesis of Spirooxindolo-β-Lactams by Staudinger Cycloaddition with TsCl as Activating Co-reagent.

ACS Omega 2021 Sep 26;6(35):22740-22751. Epub 2021 Aug 26.

Department of Chemistry, Lomonosov Moscow State University, Leninskie gory 1/3, 119991 Moscow, Russian Federation.

A convenient and versatile one-pot method for synthesis of 1,3-bis-aryl spirooxindolo-β-lactams from isatin Schiff bases and substituted phenylacetic acids using ketene-imine cycloaddition reaction with TsCl for a ketene generation has been developed. The reaction procedure does not require absolute solvents and unstable starting reagents. The studied reactions lead to -diastereoselective β-lactam formation for all tested phenylacetic acids except 4-MeOCHCHCOOH. Read More

View Article and Full-Text PDF
September 2021

Synthesis and anti-proliferation activity evaluation of novel 2-chloroquinazoline as potential EGFR-TK inhibitors.

Chem Biodivers 2021 Sep 12. Epub 2021 Sep 12.

Zhejiang University of Technology Zhaohui Campus: Zhejiang University of Technology, College of Pharmaceutical Science, No.18, Chaowang Road, Xiacheng District, Hangzhou City, Zhejiang Province, 310014, Hang Zhou, CHINA.

A novel series of 2-chloroquinazoline derivatives had been synthesized and their anti-proliferation activities against the four EGFR high-expressing cells A549, NCI-H1975, AGS and HepG2 cell lines were evaluated. The preliminary SAR study of the scaffold of new compounds showed that the compounds with a chlorine substituent on R3 had a better anti-proliferation activity than those substituted by hydrogen atom or vinyl group. Among them, 2-chloro-N-(2-chloro-4-((3-chloro-4-fluorophenyl)amino)quinazolin-6-yl)acetamide (10b) had the best activity, and the corresponding IC50 were 3. Read More

View Article and Full-Text PDF
September 2021

Design, synthesis and antibacterial activity of chalcones against MSSA and MRSA planktonic cells and biofilms.

Bioorg Chem 2021 Aug 31;116:105279. Epub 2021 Aug 31.

Laboratory of Antibiotics and Chemotherapeutics, Department of Chemistry and Environmental Sciences, Institute of Biosciences, Humanities and Exact Sciences, São Paulo State University, São José do Rio Preto, SP, Brazil. Electronic address:

Staphylococcus aureus is the one of the most successful modern pathogens. The same bacterium that lives as a skin and mucosal commensal can be transmitted in health-care and community-settings and causes severe infections. Thus, there is a great challenge for a discovery of novel anti-Staphylococcus aureus compounds, which should act against resistant strains. Read More

View Article and Full-Text PDF

Exploration of brominated Plastoquinone analogs: Discovery and structure-activity relationships of small antimicrobial lead molecules.

Bioorg Chem 2021 Sep 2;116:105316. Epub 2021 Sep 2.

Department of Chemistry, Faculty of Science, Istanbul University, Fatih, Istanbul, Turkey. Electronic address:

In the fight with the antimicrobial resistance, our continuous effort to find quinone analogs with higher inhibitory activity has previously led us to the promising Plastoquinone analogs. The 1,4-quinone moiety substituted with alkoxy substituent(s) plays an important role in the field of antimicrobial and anticancer drug discovery and development. Thus, an extensive series of 1,4-quinones, substituted in different positions with a variety of alkoxy substituents, has been designed, synthesized, and evaluated for their antimicrobial activity. Read More

View Article and Full-Text PDF
September 2021

Synthesis and biological evaluation of selected 7H-pyrrolo[2,3-d]pyrimidine derivatives as novel CDK9/CyclinT and Haspin inhibitors.

Chem Biol Interact 2021 Sep 8:109643. Epub 2021 Sep 8.

Centre of Excellence for Pharmaceutical Sciences, North-West University, Private Bag X6001, Potchefstroom, 2520, South Africa. Electronic address:

Protein kinases, including CDK9/CyclinT and Haspin, are regarded as potential drug targets in cancer therapy. Findings from a previous study suggested 7-azaindole as a privileged scaffold for producing inhibitors of CDK9/CyclinT and Haspin. Inspired by these findings, the current study synthesised and evaluated thirteen (13) C6-substituted 7-azaindole and twenty (20) C4-substituted structurally related 7H-pyrrolo[2,3-d]pyrimidine derivatives against a panel of protein kinases, including CDK9/CyclinT and Haspin. Read More

View Article and Full-Text PDF
September 2021

Design, Synthesis, biological Evaluation, and molecular docking studies of novel Pyrazolo[3,4-d]Pyrimidine derivative scaffolds as potent EGFR inhibitors and cell apoptosis inducers.

Bioorg Chem 2021 Sep 4;116:105325. Epub 2021 Sep 4.

Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy (Boys), Al-Azhar University, Cairo 11884, Egypt.

A series of novel hybrid pyrazolo[3,4-d]pyramidine derivatives was designed and chemically synthesized in useful yields. The synthesized compounds were structurally characterized by the usual techniques. All the new synthesized compounds were biologically screened in vitro for their antiproliferative activities against a panel of four cancer cell lines, namely HepG-2, MCF-7, HCT-116, and Hela. Read More

View Article and Full-Text PDF
September 2021

Synthesis, Physicochemical, Computational and Biological Evaluation of Phenylurea Derivatives as CNS agents.

Cent Nerv Syst Agents Med Chem 2021 Sep 8. Epub 2021 Sep 8.

Faculty of Pharmacy, IFTM University, Lodhipur, Moradabad (UP) 244001. India.

Background: A series of phenylurea derivatives were designed and synthesized, The target compounds were subjected to pharmacological studies. Various other parameters such as physicochemical properties, computational studies, and % similarity were also calculated.

Materials And Methods: The synthesis of the target compounds has been carried out by reaction of Phenylurea with chloroacetyl chloride to afford 1-(2-chloroacetyl)-3-phenylurea, which further reacted with substituted anilines. Read More

View Article and Full-Text PDF
September 2021

A Review on Synthesis, Structural, Flame Retardancy and Dielectric Properties of Hexasubstituted Cyclotriphosphazene.

Polymers (Basel) 2021 Aug 30;13(17). Epub 2021 Aug 30.

Sustainable Materials and Renewable Energy (SMRE) Research Group, Faculty of Science and Natural Resources, Universiti Malaysia Sabah (UMS), Kota Kinabalu 88400, Sabah, Malaysia.

Hexachlorocyclotriphosphazene is a ring compound consisting of an alternating phosphorus and nitrogen atom with two chlorine substituents attached to the phosphorus atom. The six chlorine atoms attached to this cyclo compound can be substituted with any different nucleophile that leads to changes in different chemical and physical properties. The major topics that were investigated in this research are the flame retardancy and dielectric properties of cyclotriphosphazene compounds. Read More

View Article and Full-Text PDF

Novel Sulfonamide-Based Carbamates as Selective Inhibitors of BChE.

Int J Mol Sci 2021 Aug 31;22(17). Epub 2021 Aug 31.

Institute of Organic Chemistry and Technology, Faculty of Chemical Technology, University of Pardubice, Studentska 573, 532 10 Pardubice, Czech Republic.

A series of 14 target benzyl [2-(arylsulfamoyl)-1-substituted-ethyl]carbamates was prepared by multi-step synthesis and characterized. All the final compounds were tested for their ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) in vitro, and the selectivity index (SI) was determined. Except for three compounds, all compounds showed strong preferential inhibition of BChE, and nine compounds were even more active than the clinically used rivastigmine. Read More

View Article and Full-Text PDF

Physicochemical Characterization and Drug Release Properties of Methyl-Substituted Silica Xerogels Made Using Sol-Gel Process.

Int J Mol Sci 2021 Aug 25;22(17). Epub 2021 Aug 25.

Neutron Spectroscopy Department, Centre for Energy Research, Konkoly-Thege 29-33, 1121 Budapest, Hungary.

In this work, a multi-analytical approach involving nitrogen porosimetry, small angle neutron and X-ray scattering, Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopies, X-ray diffraction, thermal analysis and electron microscopy was applied to organically modified silica-based xerogels obtained through the sol-gel process. Starting from a tetraethoxysilane (TEOS) precursor, methyltriethoxysilane (MTES) was added to the reaction mixture at two different pH values (2.0 and 4. Read More

View Article and Full-Text PDF

Design, Synthesis and SAR in 2,4,7-Trisubstituted Pyrido[3,2-]Pyrimidine Series as Novel PI3K/mTOR Inhibitors.

Molecules 2021 Sep 2;26(17). Epub 2021 Sep 2.

Institut de Chimie Organique et Analytique, Université d'Orléans, UMR CNRS 7311, rue de Chartres, BP 6759, 45067 Orléans, France.

This work describes the synthesis, enzymatic activities on PI3K and mTOR, in silico docking and cellular activities of various uncommon 2,4,7 trisubstituted pyrido[3,2-]pyrimidines. The series synthesized offers a chemical diversity in C-7 whereas C-2 (3-hydroxyphenyl) and C-4 groups (morpholine) remain unchanged, in order to provide a better understanding of the molecular determinants of PI3K selectivity or dual activity on PI3K and mTOR. Some C-7 substituents were shown to improve the efficiency on kinases compared to the 2,4-di-substituted pyrimidopyrimidine derivatives used as references. Read More

View Article and Full-Text PDF
September 2021

Synthesis of New Highly Functionalized 1-Indole-2-carbonitriles via Cross-Coupling Reactions.

Molecules 2021 Aug 31;26(17). Epub 2021 Aug 31.

Laboratoire Synthèse et Isolement de Molécules BioActives EA 7502 SIMBA, Department of Chemistry, Faculté des Sciences et Techniques de Tours, Université de Tours, Parc de Grandmont, 37200 Tours, France.

An approach for the preparation of polysubstituted indole-2-carbonitriles through a cross-coupling reaction of compounds 1-(but-2-ynyl)-1-indole-2-carbonitriles and 1-benzyl-3-iodo-1-indole-2-carbonitriles is described. The reactivity of indole derivatives with iodine at position 3 was studied using cross-coupling reactions. The Sonogashira, Suzuki-Miyaura, Stille and Heck cross-couplings afforded a variety of di-, tri- and tetra-substituted indole-2-carbonitriles. Read More

View Article and Full-Text PDF

Single Isomer -Heterocyclic Cyclodextrin Derivatives as Chiral Selectors in Capillary Electrophoresis.

Molecules 2021 Aug 30;26(17). Epub 2021 Aug 30.

Department of Pharmacognosy, Semmelweis University, Üllői út 26, H-1085 Budapest, Hungary.

In order to better understand the chiral recognition mechanisms of positively charged cyclodextrin (CD) derivatives, the synthesis, the p determination by H nuclear magnetic resonance (NMR)-pH titration and a comparative chiral capillary electrophoretic (CE) study were performed with two series of mono-substituted cationic single isomer CDs. The first series of selectors were mono-(6--pyrrolidine-6-deoxy)-β-CD (PYR-β-CD), mono-(6--piperidine-6-deoxy)-β-CD (PIP-β-CD), mono-(6--morpholine-6-deoxy)-β-CD (MO-β-CD) and mono-(6--piperazine-6-deoxy)-β-CD (PIPA-β-CD), carrying a pH-adjustable moiety at the narrower rim of the cavity, while the second set represented by their quaternarized, permanently cationic counterparts: mono-(6--(-methyl-pyrrolidine)-6-deoxy)-β-CD (MePYR-β-CD), mono-(6--(-methyl-piperidine)-6-deoxy)-β-CD (MePIP-β-CD), mono-(6--(-methyl-morpholine)-6-deoxy)-β-CD (MeMO-β-CD) and mono-(6--(4,4--dimethyl-piperazine)-β-CD (diMePIPA-β-CD). Based on pH-dependent and selector concentration-dependent comparative studies of these single isomer -heterocyclic CDs presented herein, it can be concluded that all CDs could successfully be applied as chiral selectors for the enantiodiscrimination of several negatively charged and zwitterionic model racemates. Read More

View Article and Full-Text PDF