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Cuiwei Yan - One of the best experts on this subject based on the ideXlab platform.
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synthesis and structure of new tetracopper ii complexes with n benzoate n 3 diethylamino propyl Oxamide as a bridging ligand the influence of hydrophobicity on enhanced dna bsa binding and anticancer activity
Journal of Photochemistry and Photobiology B-biology, 2016Co-Authors: Kang Zheng, Meijiao Zhang, Cuiwei YanAbstract:Abstract Two new tetracopper(II) complexes bridged by N-benzoate-N′-[3-(diethylamino)propyl]Oxamide (H3bdpox), and ended with 4,4′-dimethyl-2,2′-bipyridine (Me2bpy) or 2,2′-bipyridine (bpy), namely [Cu4(bdpox)2(Me2bpy)2](pic)2 (1) and [Cu4(bdpox)2(bpy)2](pic)2·2H2O (2) (where pic denotes the picrate anion) have been synthesized and characterized by X-ray single-crystal diffraction and other methods. In both complexes, four copper(II) ions are bridged alternately by the cis-oxamido and the carboxylato groups of two bdpox3 − ligands to form a centrosymmetric cyclic tetranuclear cation, in which, the copper(II) ions at the endo- and exo-sites of cis-bdpox3 − ligand have square-planar and square-pyramidal coordination geometries, respectively. The reactivity towards DNA/BSA suggests that these complexes can interact with HS-DNA through the intercalation mode and the binding affinity varies as 1 > 2 depending on the hydrophobicity, and effectively quench the fluorescence of protein BSA via a static mechanism. In vitro anticancer activities showed that the two complexes are active against the selected tumor cell lines, and the anticancer activities are consistent with their DNA-binding affinity.
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synthesis and structure of a new tetracopper ii complex with n benzoate n 2 2 hydroxyethylamino ethyl Oxamide as bridging ligand in vitro anticancer activities and dna and bsa binding studies
Journal of Coordination Chemistry, 2013Co-Authors: Tingting Xing, Shuhui Zhan, Cuiwei YanAbstract:A new tetracopper(II) complex bridged by oxamido and carboxylate, [Cu4(bhyox)2(phen)2(H2O)2](pic)2, where H3bhyox, phen and Hpic denote N-benzoate-N′-[2-(2-hydroxyethylamino)ethyl]Oxamide, 1,10-phenanthroline, and 2,4,6-trinitrophenol, respectively, has been synthesized and characterized by elemental analysis, molar conductivity, IR, electronic spectra, and single-crystal X-ray diffraction. The crystal structure reveals that the cyclic tetracopper(II) cation [Cu4(bhyox)2(phen)2(H2O)2]2+ with an embedded center of inversion is assembled by a pair of cis-oxamido-bridged bicopper(II) units via carboxylate bridges, in which copper(II) ions are distorted square pyramidal. The Cu⋯Cu separations through the oxamido and the carboxylate bridges are 5.1944(6) and 5.3344(7) A, respectively. In the crystal, the supramolecular structure is composed of classical hydrogen bonding chains assembled by 2D non-classical hydrogen-bonding networks and π–π stacking interaction. In vitro cytotoxicity experiment shows that the t...
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syntheses and structures of new trimetallic complexes bridged by n 5 chloro 2 hydroxyphenyl n 3 dimethylamino propyl Oxamide cytotoxic activities and reactivities towards dna and protein
Journal of Photochemistry and Photobiology B-biology, 2013Co-Authors: Cuiwei YanAbstract:Two new μ-oxamido-bridged trinuclear complexes, namely [Cu(3)L(2)(H(2)O)(2)]{[Cu(3)L(2)]·2H(2)O}(2) (1) and [Ni(3)L(2)(H(2)O)(DMF)](H(2)O)(DMF) (2), where L(3-) is deprotonated N-(5-chloro-2-hydroxyphenyl)-N'-[3-(dimethylamino)propyl]Oxamide, have been synthesized and characterized by X-ray single-crystal diffraction. The structure of complex 1, which consists of three tricopper(II) neutral molecules, lies on an inversion centre at Cu5 atom and thus has a trans conformation. The structure of complex 2 composes of a trinickel(II) neutral molecule. In vitro cytotoxic activities, and the reactivities of the two complexes towards DNA and protein are investigated. Cytotoxicities experiments reveal that the two trinuclear complexes both exhibits cytotoxic effects against human hepatocellular carcinoma cell SMMC-7721 and human lung adenocarcinoma cell A549. The interactions of the two complexes with herring sperm DNA (HS-DNA) are investigated by using UV absorption and fluorescence spectra and viscometry. The results suggested that both of the two trinuclear complexes could interact with HS-DNA through the intercalation mode and follow the binding affinity order of 1>2. The reactivity towards protein BSA revealed that the quenching of BSA fluorescence by the two complexes are static quenching, and complex 1 exhibits a higher BSA-binding ability than that of complex 2.
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syntheses and structures of tetracopper ii complexes with an n benzoate n 3 2 hydroxylethylammino propyl Oxamide ligand reactivity towards dna cytotoxic and antimicrobial activities
New Journal of Chemistry, 2012Co-Authors: Cuiwei YanAbstract:Two new tetracopper(II) complexes with formulae of [Cu4(bhpox)2(dabt)2](ClO4)2 (1) and [Cu4(bhpox)2(dmbt)2](ClO4)2·2H2O (2), where H3bhpox stands for N-benzoate-N′-[3-(2-hydroxyl-ethylammino)propyl]Oxamide, dabt and dmbt are 2,2′-diamino-4,4′-bithiazole and 2,2′-dimethyl-4,4′-bithiazole, respectively, have been synthesized and characterized by elemental analyses, molar conductivity measurements, IR and electronic spectral studies and single-crystal X-ray diffraction. The crystal structures reveal that both of the tetracopper(II) complexes are assembled by a pair of oxamido-bridged bicopper(II) units through carboxyl bridges, but the configuration of the μ-oxamido-bridge is cis- in complex 1 while trans- in complex 2. All the copper(II) ions in the two tetranuclear complexes are located in a square-pyramidal environment. Through hydrogen bonds, the two tetracopper(II) complexes 1 and 2 are assembled into a three-dimensional supramolecular structure and a two-dimensional network structure, respectively. The reactivity towards DNA, cytotoxic and antibacterial studies show that both the tetracopper(II) complexes can bind to HS-DNA in the mode of intercalation, and the cytotoxic and antibacterial activities are consistent with their DNA-binding abilities, following the order of 1 < 2. The influence of the substituents on terminal ligands in the two tetracopper(II) complexes on the structure, reactivity towards DNA, cytotoxic and antibacterial activities is preliminarily discussed.
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syntheses and structures of new dicopper ii complexes bridged by n 2 hydroxyphenyl n 3 aminopropyl Oxamide dna binding properties and cytotoxic activities
New Journal of Chemistry, 2012Co-Authors: Lin Tao, Cuiwei YanAbstract:Three new μ-oxamido-bridged dicopper(II) complexes with the formulae [Cu2(papo)(phen)(H2O)](ClO4)·2H2O (1), [Cu2(papo)(bpy)(H2O)](NO3)·H2O (2) and [Cu2(papo)(Me2bpy)(NO3)]·H2O (3) [H3papo = N-(2-hydroxyphenyl)-N′-(3-aminopropyl)Oxamide; phen = 1,10-phenanthroline; bpy = 2,2′-bipyridine; Me2bpy = 4,4′-dimethyl-2,2′-bipyridine], have been synthesized and characterized by elemental analyses, molar conductance measurements, IR and electronic spectra studies and X-ray single-crystal diffraction. In the three dicopper(II) complexes, the coordination environments around the copper(II) atoms are different: Cu1 and Cu2 atoms have a square-planar and a square- pyramidal geometry, respectively. The Cu⋯Cu distances through the cis-papo3−-bridge in complexes 1, 2 and 3 are 5.1936(7), 5.1967(7) and 5.1919(15) A, respectively. In the crystals of the three dicopper(II) complexes, there are abundant hydrogen bonds contributing to the complicated supramolecular structure. The reactivity towards DNA, and cytotoxic studies show that all three dicopper(II) complexes can bind to herring sperm DNA (HS-DNA) in the mode of intercalation, and the cytotoxic activities are consistent with their DNA-binding abilities, following the order of 1 > 2 > 3. The influence of structural variation of the terminal ligands in the dinuclear complexes on the DNA-binding property and cytotoxic activity is preliminarily discussed.
Rosalinda Contreras - One of the best experts on this subject based on the ideXlab platform.
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hypervalent and binuclear silicon and germanium derivatives from bis 3 5 di tert butyl 2 phenol Oxamide
Journal of Organometallic Chemistry, 2007Co-Authors: Victor M Jimenezperez, Carlos Camachocamacho, Rosalinda Contreras, Angel Ramosorganillo, Raul Ramireztrejo, Adrian Penahueso, Angelina FloresparraAbstract:Abstract The reactions of bis-(3,5-di- tert -butyl-2-phenol)Oxamide ( 1 ) with Cl 2 SiR 2 (Me or Ph) or Cl 2 GeR 2 (Me, n Bu or Ph) in THF provided binuclear pentacoordinated silicon and germanium compounds: bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-dimethylsilane ( 2 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-diphenylsilane ( 3 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-dimethylgermane ( 4 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-di- n -butylgermane ( 5 ) and bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-diphenylgermane ( 6 ). The mono-nuclear tetracoordinated silicon compounds N -acetyl-bis-(3,5-di- tert -butyl-2-oxo-phenyl)-amide-bis-(dimethylsilane) ( 8 ) and N -acetyl-bis-(3,5-di- tert -butyl-2-oxo-phenyl)-amide-bis-(diphenylsilane) ( 9 ) were synthesized from N -( 3 , 5 - di - tert - butyl - 2 - phenol ) acetamide ( 7 ) and Cl 2 SiR 2 (R = Me and Ph). Comparison of the 29 Si NMR chemical shifts of the penta- ( 2 and 3 ) and tetracoordinated ( 8 and 9 ) silicon compounds provided information about the intramolecular coordination of the carbonyl group to the silicon atom. Compounds 3 and 6 were characterized by single-crystal X-ray analyses. They have planar hexacyclic structures where the central atoms present distorted tbp geometries with one nitrogen and two carbon atoms in equatorial positions and two oxygen atoms in apical positions.
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new hexacyclic binuclear tin complexes derived from bis 3 5 di tert butyl 2 phenol Oxamide
Journal of Organometallic Chemistry, 2000Co-Authors: Victor M Jimenezperez, Carlos Camachocamacho, Marisol Guizadorodriguez, Heinrich Noth, Rosalinda ContrerasAbstract:Abstract The syntheses of bis-(3,5-di-tert-butyl-2-phenol)Oxamide (2a) and four new hexacyclic bimetallic tin compounds derivatives are reported: bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis(dibutyltin) (3), bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(diphenyltin) (4), bis(triethylammonium) bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(dichlorobutyl-stannate) (5), and bis-[(OSn) ethanol]-bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(chlorophenyltin) (6). All tin compounds show a planar ligand skeleton in which each tin atom is linked to the phenoxy group, to the anilinic nitrogen atom and to the oxygen of the Oxamide group. Compounds 3 and 4 have two pentacoordinated diorganyl tin atoms with a distorted bpt geometry, whereas 5 contains a dianionic structure with two hexacoordinated tin atoms bonded to a n-butyl group and to two chlorine atoms and two triethyl ammonium as counterions. Compound 6 has two hexacoordinated tin atoms, each atom is bonded, in addition to the ligand, to one phenyl and one chlorine and coordinated to an ethanol molecule. Characterization of the compounds was made through usual analytical and spectroscopic methods. Structures of 4,6-di-tert-butyl-1-phenol-2-amine 1, the Oxamide 2a and the four tin compounds 3–6 were established by the X-ray diffraction analyses.
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THREE-CENTER INTRAMOLECULAR HYDROGEN BONDING IN Oxamide DERIVATIVES. NMR AND X-RAY DIFFRACTION STUDY
Journal of the Chemical Society Perkin Transactions 2, 1998Co-Authors: Francisco J. Martínez-martínez, Itzia I. Padilla-martínez, M. A. Brito, E. D. Geniz, R. C. Rojas, J. B. R. Saavedra, Herbert Höpfl, Margarita Tlahuextl, Rosalinda ContrerasAbstract:This contribution describes the synthesis and structural investigation of the symmetric and non-symmetric Oxamides N,N′-bis(2-hydroxyphenyl)Oxamide 1, N,N′-bis(5-tert-butyl-2-hydroxyphenyl)Oxamide 2, N,N′-bis(3,5-dimethyl-2-hydroxyphenyl)Oxamide 3, N,N′-bis(2-hydroxybenzyl)Oxamide 4, N,N′-diphenethylOxamide 5, N-(2-hydroxyphenyl)-N′-(2-methoxyphenyl)Oxamide 6, N-(2-hydroxyphenyl)-N′-phenethylOxamide 7, (1S,2R)-(–)-N-(2-hydroxyphenylcarbamoylcarbonyl)norephedrine 8, (1R,2S)-(–)-N-(2-hydroxyphenylcarbamoylcarbonyl) 9, ethyl N-(2-hydroxyphenyl)oxalamate 10 and ethyl N-(2-methoxyphenyl)oxalamate 11. The structures were established by 1H, 13C, 15N and variable temperature NMR spectroscopy. Compounds 1–4 and 6–11 are stabilized by intramolecular three-center hydrogen bonding between the amide proton and two oxygen atoms. The 1H NMR Δδ/ΔT value of the amide proton correlates with the 15N NMR chemical shift. The X-ray diffraction molecular structures of 1 and 11 showed a planar conformation with trans configuration in the solid state, corresponding to the preferred conformation found in solution.
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1 H, 13C, 15N, 2D and variable temperature NMR study of the role of hydrogen bonding in the structure and conformation of Oxamide derivatives
J. Chem. Soc. Perkin Trans. 2, 1993Co-Authors: Francisco J. Martínez-martínez, Margarita Tlahuextl, Armando Ariza-castolo, Hugo Tlahuext, Rosalinda ContrerasAbstract:The structure and conformation of N,N′-bis[(2-hydroxy)phenyl]Oxamide (1); N,N′-bis[(2-methoxy)-phenyl]Oxamide (2); N,N′-bis(phenyl)Oxamide (3); N,N′-bis[(1R,2S)-(–)-norephedrine]Oxamide (4); N,N′-bis[(1R,2R)-(–)-norpseudoephedrine]Oxamide (5); N-[(2-hydroxy)phenyl]methylamide (6); N-[(2-methoxy)phenyl]methylamide (7); N-phenylmethylamide (8); N-[(–)-norephedrine]-methylamide (9) and N-[(–)-norpseudoephedrine]methylamide (10) were unambiguously established by 1H, 13C, 15N, 2D and variable temperature NMR spectroscopy. A careful NMR investigation of the conformational behaviour in these systems was relevant. It has been found that the dicarbonylic group in compounds 1–5 has a trans geometry, stabilized by intramolecular hydrogen bonding and that they possess a C2 axis. Compounds 1 and 2 are planar and compounds 1, 2, 4 and 5 present the amidic proton coordinated by two oxygen atoms.
Victor M Jimenezperez - One of the best experts on this subject based on the ideXlab platform.
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hypervalent and binuclear silicon and germanium derivatives from bis 3 5 di tert butyl 2 phenol Oxamide
Journal of Organometallic Chemistry, 2007Co-Authors: Victor M Jimenezperez, Carlos Camachocamacho, Rosalinda Contreras, Angel Ramosorganillo, Raul Ramireztrejo, Adrian Penahueso, Angelina FloresparraAbstract:Abstract The reactions of bis-(3,5-di- tert -butyl-2-phenol)Oxamide ( 1 ) with Cl 2 SiR 2 (Me or Ph) or Cl 2 GeR 2 (Me, n Bu or Ph) in THF provided binuclear pentacoordinated silicon and germanium compounds: bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-dimethylsilane ( 2 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-diphenylsilane ( 3 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-dimethylgermane ( 4 ), bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-di- n -butylgermane ( 5 ) and bis-(3,5-di- tert -butyl-2-oxo-phenyl)-oxamido-bis-diphenylgermane ( 6 ). The mono-nuclear tetracoordinated silicon compounds N -acetyl-bis-(3,5-di- tert -butyl-2-oxo-phenyl)-amide-bis-(dimethylsilane) ( 8 ) and N -acetyl-bis-(3,5-di- tert -butyl-2-oxo-phenyl)-amide-bis-(diphenylsilane) ( 9 ) were synthesized from N -( 3 , 5 - di - tert - butyl - 2 - phenol ) acetamide ( 7 ) and Cl 2 SiR 2 (R = Me and Ph). Comparison of the 29 Si NMR chemical shifts of the penta- ( 2 and 3 ) and tetracoordinated ( 8 and 9 ) silicon compounds provided information about the intramolecular coordination of the carbonyl group to the silicon atom. Compounds 3 and 6 were characterized by single-crystal X-ray analyses. They have planar hexacyclic structures where the central atoms present distorted tbp geometries with one nitrogen and two carbon atoms in equatorial positions and two oxygen atoms in apical positions.
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new hexacyclic binuclear tin complexes derived from bis 3 5 di tert butyl 2 phenol Oxamide
Journal of Organometallic Chemistry, 2000Co-Authors: Victor M Jimenezperez, Carlos Camachocamacho, Marisol Guizadorodriguez, Heinrich Noth, Rosalinda ContrerasAbstract:Abstract The syntheses of bis-(3,5-di-tert-butyl-2-phenol)Oxamide (2a) and four new hexacyclic bimetallic tin compounds derivatives are reported: bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis(dibutyltin) (3), bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(diphenyltin) (4), bis(triethylammonium) bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(dichlorobutyl-stannate) (5), and bis-[(OSn) ethanol]-bis-(3,5-di-tert-butyl-2-oxo-phenyl)-oxamido-bis-(chlorophenyltin) (6). All tin compounds show a planar ligand skeleton in which each tin atom is linked to the phenoxy group, to the anilinic nitrogen atom and to the oxygen of the Oxamide group. Compounds 3 and 4 have two pentacoordinated diorganyl tin atoms with a distorted bpt geometry, whereas 5 contains a dianionic structure with two hexacoordinated tin atoms bonded to a n-butyl group and to two chlorine atoms and two triethyl ammonium as counterions. Compound 6 has two hexacoordinated tin atoms, each atom is bonded, in addition to the ligand, to one phenyl and one chlorine and coordinated to an ethanol molecule. Characterization of the compounds was made through usual analytical and spectroscopic methods. Structures of 4,6-di-tert-butyl-1-phenol-2-amine 1, the Oxamide 2a and the four tin compounds 3–6 were established by the X-ray diffraction analyses.
Magdalena Rowińska - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of bis-(methyl 3,4,6-tri-O-acetyl-D-glucopyranosid-2-yl)-Oxamides.
Carbohydrate Research, 2005Co-Authors: Andrzej Temeriusz, Magdalena Rowińska, Bogusława Piekarska-bartoszewiczAbstract:Abstract The synthesis of a new bis-( D -glucopyranosid-2-yl)Oxamides via the key intermediate, N -acetyl N -(methyl 3,4,6-tri- O -acetyl-α- D -glucopyranosid-2-yl) oxamic acid chloride ( 2 α) is described. Treatment of compound 2α with methyl 3,4,6-tri- O -acetyl-2-amino-2-deoxy-β- D -glucopyranoside afforded N -(methyl 3,4,6-tri- O -acetyl-α- D -glucopyranosid-2-yl)- N ′-(methyl 3,4,6-tri- O -acetyl-β- D -glucopyranosid-2-yl)-Oxamide. Reaction of 2α with 1,2-diaminoethane afforded 1,2-bis-[ N , N ′-(methyl 3′,4′,6′-tri- O -acetyl-α- D -glucopyranosid-2′-yl)]ethylOxamide as a main product, while 2- N -[ N ′-(methyl 3′,4′,6′-tri- O -acetyl-α- D -glucopyranosid-2′-yl)Oxamide]-ethyl acetamide was formed as a side product. Reaction of 2α with 1,3-diamino-2-hydroxypropane gave only 1,3-bis- N , N -[ N ′-(methyl 3′,4′,6′-tri- O -acetyl-2′-deoxy-α- D -glucopyranosid-2′-yl)-oxamido]-2-propanol.
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synthesis and solid state 13c and 1h nmr analysis of new Oxamide derivatives of methyl 2 amino 2 deoxy α d glucopyranoside and ester of amino acids or dipeptides
Carbohydrate Research, 2003Co-Authors: Andrzej Temeriusz, Magdalena Rowińska, Katarzyna Paradowska, Iwona WawerAbstract:Abstract The syntheses of new Oxamide derivatives of methyl 2-amino-2-deoxy-α- d -glucopyranoside and amino acid or peptide esters are presented. The reaction of methyl 3,4,6-tri- O -acetyl-2-acetamido-2-deoxy-α- d -glucopyranoside and oxalyl chloride gave N -(methyl 3,4,6-tri- O -acetyl-2-deoxy-α- d -glucopyranosid-2-yl) oxamic acid chloride which on reaction with the ester of Gly, l -Ala, l -Phe, GlyGly, Gly- l -Phe and Gly- l -Ala afforded N -(methyl 3,4,6-tri- O -acetyl-2-deoxy-α- d -glucopyranosid-2-yl), N ′-oxalyl-amino acid or dipeptide esters. The structure of the Oxamides was studied using 1 H, 13 C NMR in solution and solid state.
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crystal structure and solid state 13c nmr analysis of n methyl 3 4 6 tri o acetyl α and β d glucopyranosid 2 yl Oxamide derivative of p chloroaniline n n diethylamine n methylaniline and n ethylaniline
Carbohydrate Research, 2001Co-Authors: Andrzej Temeriusz, Iwona Wawer, Romana Anulewicz, Tadeusz M Krygowski, Boguslawa Piekarskabartoszewicz, Magdalena RowińskaAbstract:The X-ray diffraction analysis of N-(methyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranosid-2-yl)-N'-p-chlorophenylOxamide (1), N-(methyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranosid-2-yl)-N',N'-diethylOxamide (2), N-acetyl, N-(methyl 3,4,6-tri-O-acetyl-beta-D-glucopyranosid-2-yl), N'-methyl, N'-phenylOxamide (3), N-acetyl, N-(methyl 3,4,6-tri-O-acetyl-beta-D-glucopyranosid-2-yl), N'-ethyl, N'-phenylOxamide (4) was performed. It was found that the Oxamide group in compounds 1-4 can be characterized as two structurally independent amides because there is no pi conjugation across the oxalyl OC-CO bond. Only the Oxamide group of 1 is planar and adopts trans conformation stabilized as two intramolecular N-H...O hydrogen bonds.
Iwona Wawer - One of the best experts on this subject based on the ideXlab platform.
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synthesis and solid state 13c and 1h nmr analysis of new Oxamide derivatives of methyl 2 amino 2 deoxy α d glucopyranoside and ester of amino acids or dipeptides
Carbohydrate Research, 2003Co-Authors: Andrzej Temeriusz, Magdalena Rowińska, Katarzyna Paradowska, Iwona WawerAbstract:Abstract The syntheses of new Oxamide derivatives of methyl 2-amino-2-deoxy-α- d -glucopyranoside and amino acid or peptide esters are presented. The reaction of methyl 3,4,6-tri- O -acetyl-2-acetamido-2-deoxy-α- d -glucopyranoside and oxalyl chloride gave N -(methyl 3,4,6-tri- O -acetyl-2-deoxy-α- d -glucopyranosid-2-yl) oxamic acid chloride which on reaction with the ester of Gly, l -Ala, l -Phe, GlyGly, Gly- l -Phe and Gly- l -Ala afforded N -(methyl 3,4,6-tri- O -acetyl-2-deoxy-α- d -glucopyranosid-2-yl), N ′-oxalyl-amino acid or dipeptide esters. The structure of the Oxamides was studied using 1 H, 13 C NMR in solution and solid state.
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crystal structure and solid state 13c nmr analysis of n methyl 3 4 6 tri o acetyl α and β d glucopyranosid 2 yl Oxamide derivative of p chloroaniline n n diethylamine n methylaniline and n ethylaniline
Carbohydrate Research, 2001Co-Authors: Andrzej Temeriusz, Iwona Wawer, Romana Anulewicz, Tadeusz M Krygowski, Boguslawa Piekarskabartoszewicz, Magdalena RowińskaAbstract:The X-ray diffraction analysis of N-(methyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranosid-2-yl)-N'-p-chlorophenylOxamide (1), N-(methyl 3,4,6-tri-O-acetyl-alpha-D-glucopyranosid-2-yl)-N',N'-diethylOxamide (2), N-acetyl, N-(methyl 3,4,6-tri-O-acetyl-beta-D-glucopyranosid-2-yl), N'-methyl, N'-phenylOxamide (3), N-acetyl, N-(methyl 3,4,6-tri-O-acetyl-beta-D-glucopyranosid-2-yl), N'-ethyl, N'-phenylOxamide (4) was performed. It was found that the Oxamide group in compounds 1-4 can be characterized as two structurally independent amides because there is no pi conjugation across the oxalyl OC-CO bond. Only the Oxamide group of 1 is planar and adopts trans conformation stabilized as two intramolecular N-H...O hydrogen bonds.
