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INTRAMOLECULAR HYDROGEN BOND

Accuracy enhancement in the estimation of molecular hydration free energies by implementing the intramolecular hydrogen bond effects

Accuracy enhancement in the estimation of molecular hydration free energies by implementing the intramolecular hydrogen bond effects

... The hydration free energy function was optimized and validated using the two data sets. One contains 639 FSD molecules that were divided into 439 and 200 to consti- tute the training and test sets, respectively, and the ...

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1 [4 (3,5 Di­meth­oxy 2 methyl­phen­oxy) 2,6 di­hy­droxy 3 methyl­phenyl]­ethanone

1 [4 (3,5 Di­meth­oxy 2 methyl­phen­oxy) 2,6 di­hy­droxy 3 methyl­phenyl]­ethanone

... The bond lengths and angles observed in the structure are normal and agree reasonably with the reported values (Elix et ...in hydrogen bonding: one hydroxyl group, O4—H4A, involved as a donor in an ...

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2 (Meth­oxy­carbon­yl) 4 methyl­thio­phen 3 aminium chloride monohydrate: the first crystal structure of a 3 amino­thio­phene 2 carboxylic acid ester

2 (Meth­oxy­carbon­yl) 4 methyl­thio­phen 3 aminium chloride monohydrate: the first crystal structure of a 3 amino­thio­phene 2 carboxylic acid ester

... weak intramolecular hydrogen bond. With this hydrogen bond, the six atoms O7, C6, C2, C3, N10 and H10A form a six-membered pseudo- ...the hydrogen bond closing the ring is ...

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β Alaninium maleate

β Alaninium maleate

... Fig. 1 shows the molecular structure of (I) with the atom-numbering scheme. The β-alanine molecule exists in the cationic form with a positively charged amino group and an uncharged carboxylic acid group. The maleic acid ...

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1 (4 Methyl­piperdinemeth­yl) 2 (4 bromo­phen­yl) 6 meth­yl 8 tri­fluoro­methyl­imidazo[1,2 a][1,8]naph­thyridinium picrate

1 (4 Methyl­piperdinemeth­yl) 2 (4 bromo­phen­yl) 6 meth­yl 8 tri­fluoro­methyl­imidazo[1,2 a][1,8]naph­thyridinium picrate

... N intramolecular hydrogen bond between atoms N7 and N5, forming an intramolecular S(7) ring (Bernstein et ...O hydrogen bonds between ...strong hydrogen bond with O1A, ...

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Crystal structure of 1 (3 chloro­phen­yl)piperazin 1 ium picrate–picric acid (2/1)

Crystal structure of 1 (3 chloro­phen­yl)piperazin 1 ium picrate–picric acid (2/1)

... centre hydrogen bond involving a O3E—H3E···O4E intramolecular hydrogen bond and a weak C—H···O interaction with that of picrate ...in hydrogen bonding have been removed for ...

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DL Valinium maleate at 150 K

DL Valinium maleate at 150 K

... hydrogen bond. An asymmetric intramolecular hydrogen bond is observed in the crystal structures of maleic acid (James & Williams, 1974), glycinium maleate and l-alaninium maleate; ...

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β Alaninium perchlorate

β Alaninium perchlorate

... three-centered hydrogen bond with acceptor O atoms (O2 and O3) of the perchlorate ...three-centered hydrogen bond, with (i) the carboxyl atom O1A (intramolecular hydrogen ...

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N,N Di­methyl­biguanidium nitrate

N,N Di­methyl­biguanidium nitrate

... H···N3 hydrogen bonds, forming an elongated hexagon. The hydrogen bonding information is given in Table 2 and a packing diagram is shown in ...N—H···N intramolecular hydrogen bond ...

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A macrocyclic binuclear copper(II) complex of the ligand N,N′ bis­­(pyridin 2 yl­methyl)­pyrazine 2,3 dicarbox­amide

A macrocyclic binuclear copper(II) complex of the ligand N,N′ bis­­(pyridin 2 yl­methyl)­pyrazine 2,3 dicarbox­amide

... no intramolecular hydrogen bond involving the carbonyl O atom, O1, of the coordinated (pyridin-2-ylmethyl)amide moiety, and the NH H atom of the protonated N6-pyridine ring ...

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5 Nitro­salicylaldehyde benzoyl­hydrazone

5 Nitro­salicylaldehyde benzoyl­hydrazone

... an intramolecular hydrogen bond between the donor OH group of the salicylaldehyde moiety and the acceptor ═N–NH— group of the benzhydrazidyl moiety (Lyubchova et ...short hydrogen bond ...

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4 [(4 Methyl­phenyl)­diazenyl] 6 meth­oxy 2 {[tris­­(hy­droxy­methyl)­methyl]­amino­methyl­ene}cyclo­hexa 3,5 dien 1(2H) one

4 [(4 Methyl­phenyl)­diazenyl] 6 meth­oxy 2 {[tris­­(hy­droxy­methyl)­methyl]­amino­methyl­ene}cyclo­hexa 3,5 dien 1(2H) one

... no intramolecular hydrogen ...special bond lengths are C10ÐO1 = ...corresponding bond lengths in N-(2-¯uoro-3- methoxy)salicylaldimine, which exists in the phenol±imine tautomeric form, are ...

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L Phenyl­alaninium maleate

L Phenyl­alaninium maleate

... symmetric intramolecular hydrogen bond, with a proton shared between the O3 and O5 atoms, is observed as in the crystal structures of complexes of maleic acid with dl- and l-arginine (Ravishankar et ...

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Bis­(pyridin 2 yl­methano­lato κ2N,O)­bis­­(tri­fluoro­acetato)­nickel(II)

Bis­(pyridin 2 yl­methano­lato κ2N,O)­bis­­(tri­fluoro­acetato)­nickel(II)

... strong intramolecular hydrogen bond, but in these cases either the carbonyl O or N atoms of the saccharinate or salicylate anions are the accep- ...

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4 Iso­propyl­amino 3 nitro­benzo­nitrile

4 Iso­propyl­amino 3 nitro­benzo­nitrile

... angles (Allen et al., 1987) are within normal ranges. The nitro group is essentially coplanar with the aromatic ring forming a dihedral angle of 3.4 (3)° with the ring. The amine H atom forms an intramolecular ...

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(anti Chlorido­thio­semicabazide κS)bis­­(tri­phenyl­phosphane κP)copper(I) 0 48 hydrate

(anti Chlorido­thio­semicabazide κS)bis­­(tri­phenyl­phosphane κP)copper(I) 0 48 hydrate

... an intramolecular N—H···N hydrogen bond between N1—H1A and N3 (graph set designator as S(5) (Bernstein et ...Another intramolecular hydrogen bond, between the hydrazine N2 —H2 ...

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Quinoline 2 sulfonamide

Quinoline 2 sulfonamide

... for intramolecular hydrogen-bond five-membered ring formation (H1···N1 = ...intermolecular hydrogen bond is more difficult to break than comparable intramolecular hydrogen ...

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1 [(4 Acetyl­phenyl­amino)­methyl­ene]­naphthalen 2(1H) one

1 [(4 Acetyl­phenyl­amino)­methyl­ene]­naphthalen 2(1H) one

... The title compound, (I), adopts the keto±imine tautomeric form, with a strong intramolecular N1ÐH1 O1 hydrogen bond (Fig. 1). The rather short C1ÐO1, C18ÐO2 and C2Ð C3, C5ÐC6, C7ÐC8 bonds can be ...

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Crystal structures of two 6 (2 hy­dr­oxy­benzo­yl) 5H thia­zolo[3,2 a]pyrimidin 5 ones

Crystal structures of two 6 (2 hy­dr­oxy­benzo­yl) 5H thia­zolo[3,2 a]pyrimidin 5 ones

... Compounds (1) and (2) were synthesized in moderate/high yields by a one-pot reaction using 4-oxo-4H-chromene-3- carboxylic acid as the starting material. Chromone-3-carb- oxylic acid was initially activated with ...

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1 (5 Hydr­­oxy 3 methyl 1 phenyl 1H pyrazol 4 yl)ethanone: a new monoclinic polymorph

1 (5 Hydr­­oxy 3 methyl 1 phenyl 1H pyrazol 4 yl)ethanone: a new monoclinic polymorph

... In both molecules, there is an intramolecular O—H O hydrogen bond involving the hydroxyl substituent and the carbonyl O atom of the adjacent acetyl group. In the crystal structure, molecules A and B ...

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