scholarly journals Synthesis of multivalent carbohydrate mimetics with aminopolyol end groups and their evaluation as L-selectin inhibitors

2015 ◽  
Vol 11 ◽  
pp. 638-646 ◽  
Author(s):  
Joana Salta ◽  
Jens Dernedde ◽  
Hans-Ulrich Reissig
Keyword(s):  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Amide Bonds ◽  
H Nmr ◽  
End Groups ◽  
Full Conversion ◽  
Purification Protocol ◽  
Micromolar Range

In this article a series of divalent and trivalent carbohydrate mimetics on the basis of an enantiopure aminopyran and of serinol is described. These aminopolyols are connected by amide bonds to carboxylic acid derived spacer units either by Schotten–Baumann acylation or by coupling employing HATU as reagent. The O-sulfation employing the SO3·DMF complex was optimized. It was crucial to follow this process by 700 MHz 1H NMR spectroscopy to ensure full conversion and to use a refined neutralization and purification protocol. Many of the compounds could not be tested as L-selectin inhibitor by SPR due to their insolubility in water, nevertheless, a divalent and a trivalent amide showed surprisingly good activities with IC50 values in the low micromolar range.

Synthesis and properties of oxytocin analogues modified in the tripeptide side chain

1984 ◽  
Vol 49 (3) ◽  
pp. 642-652 ◽  
Author(s):  
Zdenko Procházka ◽  
Michal Lebl ◽  
Tomislav Barth ◽  
Jan Hlaváček ◽  
Antonín Trka ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Biological Activities ◽  
The Other ◽  
Side Chain ◽  
H Nmr ◽  
Fragment Condensation

Two oxytocin analogues were synthesized by fragment condensation (6 + 3) in the presence of dicyclohexylcarbodiimide and 1-hydroxybenzotriazole. In one of the analogues, proline in the position 7 and leucine in the position 8 were substituted by 2-[1-(2-oxo-3-aminopyrrolidinyl)]-4-methylpentanoic acid, in the other proline was replaced by 1-aminocyclopropane-1-carboxylic acid. Biological activities of the first analogue were strongly reduced and dissociation of the uterotonic and galoctogogic activities was observed with both the analogues. The structure of 2-(3-tert-butyloxycarbonylaminopyrrolidin-2-on-1-yl)-4-methylpentanoylglycine and its amide was confirmed by mass and 1 H NMR spectroscopy.

Liquid crystalline vinylcyclopropane derivatives bearing cholesteryl side groups: synthesis, characterization and polymerization

e-Polymers ◽  
2002 ◽  
Vol 2 (1) ◽  
Author(s):  
Valentina Alupei ◽  
Helmut Ritter
Keyword(s):  
Phase Transition ◽  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Ir Spectroscopy ◽  
Radical Polymerization ◽  
Liquid Crystalline ◽  
Optically Active ◽  
H Nmr

AbstractNew optically active 1,1-disubstituted 2-vinylcyclopropanes ,3a, b were synthesized by esterification of the corresponding 1-ethoxycarbonyl-2-vinylcyclopropane- 1-carboxylic acid 2a,b with cholesterol and characterized by 1H NMR and IR spectroscopy. The liquid crystalline properties of the obtained monomers are reported. The effect of the structure of the 2-vinylcyclopropane monomers on the phase transition of the mesogen was investigated. Radical polymerization of the asymmetrically substituted monomers 3a,b in solution and in bulk resulted in liquidcrystalline polymers with 1,5-opened units, as evidenced by 1H NMR spectroscopy.

Cycloaddition Reactions of Arylmethylenemalonaldehydes with Olefins

1992 ◽  
Vol 57 (11) ◽  
pp. 2337-2358 ◽  
Author(s):  
Dalimil Dvořák ◽  
David Šaman ◽  
Zdeněk Arnold ◽  
Ivana Císařová ◽  
Václav Petříček
Keyword(s):  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Vinyl Ether ◽  
Aromatic Nucleus ◽  
Ethyl Vinyl Ether ◽  
Cycloaddition Reactions ◽  
Ethyl Vinyl ◽  
X Ray ◽  
H Nmr ◽  
Conformational Equilibria

A series of 2,4-disubstituted 3,4-dihydro-2H-pyran-5-carboxaldehydes II-XIX was prepared by reaction of substituted arylmethylenemalonaldehydes I with 2-methylpropane, 1,1-diphenylethylene, styrene, ethyl vinyl ether, 1,1-dimethoxyethylene and 1,1-bis(methylthio)ethylene. In the case of the reaction with ethyl vinyl ether the dependence of the ratio of the arising cis- and trans- 2-ethoxy-4-aryl-3,4-dihydropyran-5-carboxaldehydes VII-XIV on the substitutent on the aromatic nucleus was studied. Information on the mechanism of this reaction was obtained and conformational equilibria of 2-ethoxy-4-aryl-3,4-dihydropyran-5-carboxaldehydes in solution were studied by 1H NMR spectroscopy. The structure of trans-2-ethoxy-4-(4-chlorophenyl)-3,4-dihydropyran-5-carboxaldehyde (trans-VIII) was confirmed by X-ray analysis of the corresponding carboxylic acid trans-XXII.

scholarly journals Electron Release and Proton Acceptance Reactions of (dpp-BIAN)Mg(THF)3

2008 ◽  
Vol 63 (2) ◽  
pp. 161-168 ◽  
Author(s):  
Igor L. Fedushkin ◽  
Valentina A. Chudakova ◽  
Markus Hummert ◽  
Herbert Schumann
Keyword(s):  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Ir Spectroscopy ◽  
The Other ◽  
X Ray ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Electron Release ◽  
Coordination Spheres ◽  
Centrosymmetric Dimers

(dpp-BIAN)Mg(THF)3 (1) (dpp-BIAN = 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) and (PhCOO)2 react with splitting of the peroxide bridge and formation of the dimeric magnesium benzoate [(dpp-BIAN)MgOCOPh(THF)]2 (2). The reaction of 1 with PhCOOH yields the dimeric magnesium benzoate [(dpp-BIAN)(H)MgOCOPh(THF)]2 (3), whereas 1 and furanyl-2-carboxylic acid react with liberation of hydrogen and formation of (dpp-BIAN)Mg[OCO(2-C4H3O)]2 Mg(dpp-BIAN)(THF) (4). Compounds 2, 3, and 4 have been characterized by elemental analysis, IR spectroscopy, and X-ray structure analysis, compound 3 also by 1H NMR spectroscopy. The eightmembered metallacycles of the centrosymmetric dimers 2 and 3 are almost completely planar. The two magnesium atoms in 4 show different coordination spheres; one is surrounded by its ligands in a trigonal bipyramidal manner, the other one in a tetrahedral fashion. The Mg···Mg separations in 2, 3 and 4 are 4.236, 4.296, and 4.030 Å, respectively

Synthesis of Poly(ethylene glycol) Derivatives

2013 ◽  
Vol 750-752 ◽  
pp. 1674-1677
Author(s):  
Hai Yun Chen ◽  
Yu Kai Shan ◽  
Yu Yue Qin ◽  
Guo Xian Zhou ◽  
Ming Long Yuan
Keyword(s):  
Nmr Spectroscopy ◽  
Ethylene Glycol ◽  
Biologically Active ◽  
Poly Ethylene Glycol ◽  
H Nmr ◽  
End Groups ◽  
Poly Ethylene ◽  
Ethylene Glycol Derivatives

To expand the extent of conjugation with biologically active molecules (biopolymers, peptides, drugs, etc.) and biomaterial substrates, we synthesized a serial of poly (ethy1ene glycol) (PEG) derivatives (PEG-2000-NH2, MPEG-1200-NH2, and APEG-1200-NH2) in three efficient steps. The end groups were characterized by 1H NMR spectroscopy.

scholarly journals Synthesis and characterization of alternating poly(amide urea)s and poly(amide urethane urethane)s from ε-caprolactam, diamines, and diphenyl carbonate or ethylene carbonate

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Luc Ubaghs ◽  
Bhaskar Sharma ◽  
Helmut Keul ◽  
Hartwig Höcker ◽  
Ton Loontjens ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Nmr Spectroscopy ◽  
Ethylene Carbonate ◽  
Building Blocks ◽  
Diphenyl Carbonate ◽  
Scanning Calorimetry ◽  
Molecular Weights ◽  
H Nmr ◽  
End Groups

Abstract Alternating poly(amide urea)s from ε-caprolactam, diamines H2N-(CH2)x- NH2 (x = 2 - 4), and diphenyl carbonate were prepared in two steps. The microstructure of the poly(amide urea)s, as determined by means of 1H NMR spectroscopy, reveals a strictly alternating sequence of the building blocks. The molecular weights and polydispersities obtained were 7500 < Mn < 10 000 and 1.48 < Mw/Mn < 1.56, respectively. Thermal properties were determined by means of differential scanning calorimetry (DSC) (163.9°C < Tm < 197.2°C; 55.5°C < Tg (2nd heating) < 72.2°C), and thermogravimetric analysis (TGA). TGA shows a three-step decomposition at 200, 350, and 450°C, which was attributed to the cleavage of O-phenyl urethane end groups, as well as urea and amide linkages. These assignments were made by comparison with model compounds. Furthermore, alternating poly- (amide urethane urethane)s from ε-caprolactam, diamines, and ethylene carbonate were prepared in three steps. The microstructure of the poly(amide urethane urethane)s, as determined by means of 1H NMR spectroscopy, reveals imperfections. The molecular weights and polydispersities obtained were 5400 < Mn < 17 000 and 2.08 < Mw/Mn < 2.99, respectively. Thermal properties were determined by means of DSC (155.9°C < Tm < 159.0°C; 35.5°C < Tg (2nd heating) < 39.0°C) and TGA. TGA shows a complex decomposition due to the formation of ethylene carbonate by cleavage of the urethane groups (at approx. 230°C) and formation of poly(amide urea)s. The newly formed poly(amide urea)s decompose in a similar way as the poly(amide urea)s.

Complexations of the hydrophilic and hydrophobic moieties of benzethonium chloride by cucurbit[7]uril in aqueous solution

2012 ◽  
Vol 90 (10) ◽  
pp. 851-857 ◽  
Author(s):  
Brendan C. MacGillivray ◽  
Donal H. Macartney
Keyword(s):  
Mass Spectrometry ◽  
Aqueous Solution ◽  
Nmr Spectroscopy ◽  
Stability Constant ◽  
Guest Molecule ◽  
Ionization Mass ◽  
H Nmr ◽  
Benzethonium Chloride ◽  
End Groups ◽  
Initial Binding

The sequential complexations of the hydrophilic and hydrophobic end groups of benzethonium chloride by cucurbit[7]uril (CB[7]) in aqueous solution have been investigated using 1H NMR spectroscopy and electrospray ionization mass spectrometry. The initial binding is to the benzyldimethylammonium group, with a stability constant of (8.7 ± 3.1) × 107 (mol/L)–1. This binding constant and the complexation-induced upfield shifts of the benzyl guest protons are similar to those values observed with other cationic guests containing benzyl moieties. This equilibrium is followed by the binding of a second equivalent of the host to the hydrophobic 2-(2,4,4-trimethylpentyl) group, with a stability constant of (4.0 ± 1.9) × 103 (mol/L)–1. The relatively strong binding of this uncharged hydrophobic end of the guest molecule is consistent with the inclusion of eight heavy (nonhydrogen) atoms within the inner cavity of CB[7], with its low polarizability. The packing coefficient for the 2-(2,4,4-trimethylpentyl) group with the inner cavity is calculated to be 61%, close to Rebek’s ideal value of 55%.

Darstellung und Reaktionen der Oxovanadin(V)-tricarboxylate / Synthesis and Reactions of Oxovanadium(V) Tricarboxylates

1980 ◽  
Vol 35 (7) ◽  
pp. 817-823 ◽  
Author(s):  
Fritz Preuss ◽  
Willi Towae ◽  
Joachim Woitschach
Keyword(s):  
Nmr Spectroscopy ◽  
Carboxylic Acid ◽  
Complex Formation ◽  
Chemical Reactions ◽  
Acid Anhydride ◽  
Carboxylate Ligands ◽  
H Nmr ◽  
Silver Carboxylate ◽  
Carboxylic Acid Anhydride

Monomeric oxovanadium(V) tricarboxylates VO(RCOO)3 are prepared by reaction of VOCl3 with an excess of silver carboxylate in CH2Cl2 or by depolymerization of (VO2RCOO)n in carboxylic acid anhydride. Their properties are studied by IR and 1H NMR spectroscopy as well as by chemical reactions such as thermolysis, solvolysis, redistribution and complex formation. The structure of 2,2′-dipyridyl and 1,10-phenanthroline complexes [VO(RCOO)3 · B] (B = C10H8N2, C12H8N2) has been found to be octahedral with meridional arrangement of the carboxylate ligands. Syntheses of Na[VO(CH3COO)4] and Ba[VO2(CH3COO)3] · 2CH3COOH are described

Conformational study on ribonucleoside O-phosphonylmethyl derivatives by 1H NMR spectroscopy

1985 ◽  
Vol 50 (8) ◽  
pp. 1899-1905 ◽  
Author(s):  
Milena Masojídková ◽  
Jaroslav Zajíček ◽  
Miloš Buděšínský ◽  
Ivan Rosenberg ◽  
Antonín Holý
Keyword(s):  
Nmr Spectroscopy ◽  
1H Nmr ◽  
1H Nmr Spectroscopy ◽  
Conformational Study ◽  
H Nmr ◽  
Conformational Properties

Conformational properties of ribonucleoside 5'-O-phosphonylmethyl derivatives have been determined by 1H NMR spectroscopy and compared with those of natural nucleosides and 5'-nucleotides.

Rotationsbarriere der Endgruppen bei Poly- methinoxonolen verschiedener Kettenlänge / Rotation Barrier of the End Groups of Polymethine Oxonols with Different Chain Lengths

1976 ◽  
Vol 31 (8) ◽  
pp. 1017-1018 ◽  
Author(s):  
H. Oehling ◽  
F. Baer
Keyword(s):  
Nmr Spectra ◽  
Rotation Barrier ◽  
Free Enthalpy ◽  
Temperature Dependent ◽  
Restricted Rotation ◽  
H Nmr ◽  
Enthalpy Of Activation ◽  
End Groups ◽  
Electron Contribution ◽  
Chain Lengths

Abstract Polymethine oxonols show temperature dependent 1H-NMR-spectra because of restricted rotation of the end groups. The dependence of the value of the corresponding free enthalpy of activation AGt on the length of the poly-methine chain can be explained by the change of the π-electron contribution to ⊿G≠.

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