Chloro-benzene Rings Research Articles

(E)-3-(3-Chlorophenyl)-N-(4-hydroxy-3-methoxybenzyl)acrylamide

In the title compound, C17H16ClNO3, the 4-hy­droxy-3-meth­oxy­benzyl group is planar [maximum atomic deviation = 0.0138 (16) Å] and is nearly perpendicular to the chloro­benzene ring, making a dihedral angle of 84.67 (4)°. The chloro­benzene and amide groups are located on the opposite sides of the C=C bond, showing an E configuration. The relatively long C=O bond distance of 1.2364 (19) Å and the short C—N bond distance of 1.341 (2) Å suggest electron delocalization in the amide fragment. Inter­molecular O—H⋯O, N—H⋯O and weak C—H⋯O hydrogen bonding is present in the crystal structure.

Diethyl 1-acetyl-4′-(4-chlorophenyl)-5′-(4-nitrophenyl)-2-oxospiro[indoline-3,3′-pyrrolidine]-2′,2′-dicarboxylate

In the title compound, C31H28ClN3O8, the pyrrolidine ring exhibits an envelope conformation, with the spiro C atom located at the flap position. A spiro junction links the oxindole ring system and the pyrrolidine ring. The planar oxindole ring system is twisted with respect to the nitro­benzene and chloro­benzene rings, with dihedral angles of 62.34 (11) and 75.93 (9)°, respectively. In the crystal, a weak C—H⋯O interaction links the molecules into chains and two intramolecular C—H⋯O close contacts are seen.

2-[(E)-2-(4-Chlorophenyl)ethenyl]-1-methylpyridinium 4-bromobenzenesulfonate

In the title compound, C14H13ClN+·C6H4BrO3S−, the cation exists in an E configuration with respect to the ethenyl bond and is almost planar, the dihedral angle between the pyridinium and the benzene rings being 2.80 (7)°. The dihedral angles between the benzene ring of the anion and the pyridinium and benzene rings of the cation are 80.88 (7) and 79.05 (7)°, respectively. In the crystal, the cations are stacked into columns along the a axis as a result of π–π inter­actions between the pyridinium and chloro­benzene rings with a Cg⋯Cg distance of 3.6976 (8) Å. The anions are linked into chains along the a axis by weak C—H⋯O inter­actions. These anion chains are linked to adjacent cations by additional weak C—H⋯O and C—H⋯Br inter­actions, forming a two-dimensional network parallel to the ab plane. There are also short O⋯Br [3.2567 (11) Å] and C⋯O [2.9917 (18) Å] contacts. The crystal structure is further stabilized by C—H⋯π inter­actions involving the aromatic ring of the anion.

Ethyl 2-amino-4-(3-chlorophenyl)-5,10-dioxo-5,10-dihydro-4H-benzo[g]chromene-3-carboxylate

The title mol­ecule, C22H16ClNO5, was obtained by the reaction of (E)-ethyl 3-(3-chloro­phen­yl)-2-cyano­acrylate and 2-hydroxy­naphthalene-1,4-dione catalysed by triethylamine in ethanol. In the crystal structure, the chlorobenzene ring makes a dihedral angle of 88.63 (4)° with the fused ring system. The six-membered ring formed by an intra­molecular N—H⋯O hydrogen bond is almost planar. The crystal packing is stabilized by N—H⋯O hydrogen bonds.

N-(2-Chlorophenyl)-2-(4,6-dimethylpyrimidin-2-ylsulfanyl)acetamide

In the title compound, C14H14ClN3OS, the 4,6-dimethyl­pyrimidine ring and the chloro­benzene ring subtend a dihedral angle of 80.0 (2)°. The length of the Csp 2—S bond is significantly shorter than that of the Csp 3—S bond. The crystal structure is stabilized by inter­molecular N—H⋯O, C—H⋯O and C—H⋯N hydrogen bonding, and C—H⋯π inter­actions.

3-(2-Aminoethyl)-2-(4-chloroanilino)quinazolin-4(3H)-one methanol 0.75-solvate

In the asymmetric unit of the title compound, C16H15ClN4O·0.75CH3OH, there are two independent quinazolin-4(3H)-one mol­ecules and one and a half methanol mol­ecules. One of the methanol mol­ecules is disordered over two positions with equal occupancies. The dihedral angles between the quinazoline ring system and the chloro­benzene ring in the two quinazolin-4(3H)-one mol­ecules are essentially the same, at 39.83 (1) and 39.84 (1)°. Intra­molecular N—H⋯N and O—H⋯O, and inter­molecular N—H⋯O and N—H⋯N hydrogen bonds are observed. In addition, π–π stacking inter­actions, with centroid-to-centroid distances of 3.654 (1), 3.766 (1) and 3.767 (1) Å, and weak C—H⋯π inter­actions, are observed.

Phototransformation of the drug trazodone in aqueous solution

Irradiation of trazodone at 310 nm in water has been investigated. In addition to the OH-substitution in the chlorobenzene ring a peculiar dimerization of the dihydropyridine moiety leading to a cage-like product was involved in the photo-induced modification of the drug. The photoproducts, isolated by chromatographic techniques, have been identified by spectroscopic means. Further support of the structure of the cage-like product was sought by a comparison between the experimental chemical shifts and the values computed at the DFT level.

2,3-Bis(2-chloro-benz-yl)naphthalene-1,4-dione.

The title disubstituted naphthalene-1,4-dione, C24H16Cl2O2, has the two chloro­benzyl substituents related by a non-crystallographic twofold rotation axis, generating a chiral conformation; both enantiomers are present. The two chlorobenzene rings are nearly perpendicular to the fused ring system, making angles of 88.8 (1) and 77.5 (1)° with it.

Ethyl 2-benzylsulfanyl-7-(2-chlorophenyl)-5-methyl-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine-6-carboxylate

In the title compound, C22H21ClN4O2S, the bicyclic triazolopyrimidine ring system is nearly planar, and oriented at dihedral angles of 89.45 (3)° with respect to the chlorobenzene ring and 87.03 (3)° with respect to the terminal phenyl ring. In the crystal structure, mol­ecules are linked by π–π stacking inter­actions between the triazolopyrimidine rings [centroid–centroid distances of 3.88 (1) and 3.63 (1) Å].

4-(4-Chlorobenzyloxy)-3-methoxybenzaldehyde

In the title compound, C15H13ClO3, the vanillin group makes a dihedral angle of 72.79 (9)° with the chlorobenzene ring. The crystal structure is stabilized by weak non-classical intermolecular C—H...O hydrogen bonds that form centrosymmetric dimers.

1-(4-tert-Butylbenzyl)-3-(4-chlorophenyl)-1H-pyrazole-5-carboxylic acid

In the title compound, C21H21ClN2O2, the pyrazole and chlorobenzene rings are coplanar and make a dihedral angle of 79.7 (2)° with the tert-butyl­benzene ring. The crystal structure displays inter­molecular O—H⋯O hydrogen bonding.

Crystal Structure of Anti-Configuration of Indomethacin and Leukotriene B4 12-Hydroxydehydrogenase/15-Oxo-Prostaglandin 13-Reductase Complex Reveals the Structural Basis of Broad Spectrum Indomethacin Efficacy

The crystal structure of the ternary complex of leukotriene B4 12-hydroxydehydrogenase/15-oxo-prostaglandin (15-oxo-PG) 13-reductase (LTB4 12HD/PGR), an essential enzyme for eicosanoid inactivation pathways, with indomethacin and NADP+ has been solved. An indomethacin molecule bound in the anti-configuration at one of the two active site clefts of the homo-dimer interface in the LTB4 12HD/PGR and was confirmed by a binding calorimetry. The chlorobenzene ring is buried in the hydrophobic pore used as a binding site by the omega-chain of 15-oxo-PGE2. The carboxyl group interacts with the guanidino group of Arg56 and the phenolic hydroxyl group of Tyr262. Indomethacin shows a broad spectrum of efficacy against lipid-mediator related proteins including cyclooxygenase-2, phospholipase A2, PGF synthase and PGE synthase-2 but in the syn-configuration as well as LTB4 12HD/PGR in the anti-configuration. Indomethacin does not necessarily mimic the binding mode of the lipid-mediator substrates in the active sites of these complex structures. Thus, the broad spectrum of indomethacin efficacy can be attributed to its ability to adopt a range of different stable conformations. This allows the indomethacin to adapt to the distinct binding site features of each protein whilst maintaining favorable interactions between the carboxyl group and a counter charged functional group.

(E)-4-[4-(4-Chlorobenzyloxy)-3-methoxybenzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

The title compound, C26H24ClN3O3, was prepared by the reaction of 4-amino-1,5-dimethyl-2-phenylpyrazol-3-one and 4-(4-chlorobenzyloxy)-3-methoxybenzaldehyde. The vanillin group makes dihedral angles of 6.21 (10) and 48.05 (6)°, respectively, with the pyrazolone and chlorobenzene rings. The crystal packing is governed by C—H...O hydrogen bonds and C—H...π and π–π interactions.

(E)-4-[3-(4-Chlorobenzyloxy)-4-methoxybenzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

In the title compound, C26H24ClN3O3, the vanillin group makes dihedral angles of 8.09 (9), 74.91 (8) and 44.66 (9)° with the pyrazolone ring, the terminal chlorobenzene ring and the terminal phenyl ring, respectively. The crystal packing is stabilized by intermolecular C—H...O hydrogen bonds.

(E)-4-[4-(4-Chlorobenzyloxy)-3-ethoxybenzylideneamino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

The title compound, C27H26ClN3O3, was prepared by reacting 4-amino-1,5-dimethyl-2-phenylpyrazol-3-one and 4-(4-chlorobenzyloxy)-3-ethoxybenzaldehyde. The central ethylvanillin group makes dihedral angles of 63.00 (11), 31.83 (7) and 74.47 (8)° with the chlorobenzene ring, the pyrazolone ring and the terminal phenyl ring, respectively. Packing is stabilized by intermolecular C—H...O hydrogen bonds that form centrosymmetric dimers.

The Biodegradation of 1,3-Dichlorobenzene by an Adapted Strain Bacillus cereus PF-11 Derived from Town-Gas Industrial Effluent

In the present study, an adapted bacterium PF-11 with high 1,3-dichlorobenzene degradation capability was isolated from town-gas industrial effluent through continuous introducing of N-methyl-N ′-nitro-N-nitrosoquanidine (NTG). In suitable condition, a degradation rate of 32 mg L−1d−1 of 1,3-dichlorobenzene was obtained by strain PF-11 with effective chlorion release. Strain PF-11 was tentatively identified as gram-positive Bacillus cereus. The substrate specificity of the strain PF-11 was relatively low, and the degradation rate for different chlorobenzenes was in the order of monochlorobenzene > 1,3-dichlorobenzene >1,2-dichlorobenzene. Initial oxidation step was molecular oxygen attacking chlorobenzene ring catalyzed by dioxygenase.

Synthesis and anticonvulsant activity of 3‐[3‐[(dimethylamino)‐methyl]‐5‐methyl‐4H‐1,2,4‐triazol‐4‐yl]‐4‐(o‐chlorobenzoyl)pyridine

AbstractWolff‐Kishner reduction of 3‐amino‐4‐(o‐chlorobenzoyl)pyridine (3) afforded 3‐amino‐4‐(o‐chlorobenzyl)pyridine (5), which on subsequent reaction with triethyl orthoformate and then acetyl hydrazide yielded 1‐acetyl‐2‐[N‐[4‐(o‐chlorobenzyl)pyridin‐3‐yl]formimidoyl]hydrazone (7). Cyclization of hydrazone 7 gave 3‐(3‐methyl‐4H‐1,2,4‐triazol‐4‐yl)‐4‐(o‐chlorobenzyl)pyridine (8), which on Jones oxidation yielded 3‐(3‐methyl‐4H‐1,2,4‐triazol‐4‐yl)‐4‐(o‐chlorobenzyl)pyridine (9). The Mannick reaction of 3‐(3‐methyl‐4H‐l,2,4‐triazol‐4‐yl)‐4‐(o‐chlorobenzyl)pyridine (9) with aqueous formalin and dimethylamine hydrochloride afforded 3‐[3‐[(dimethylamino)methyl]‐5‐methyl‐4H‐1,2,4‐triazol‐4‐yl]‐4‐(o‐chlorobenzoyl)‐pyridine (10). 3‐[3‐[(Dimethylamino)methyl]‐5‐methyl‐4H‐1,2,4‐triazol‐4‐yl]‐4‐(o‐chlorobenzoyl)pyridine (10) exhibited good anticonvulsant activity in the subcutaneous pentylenetetrazole anticonvulsant screen indi cating that an appropriately substituted‐pyridine ring moiety can serve as a bioisostere of a chlorobenzene ring with respect to anticonvulsant activity.

Structure of 2,10 dichloro 6-(2,3 dimethylphenoxy) dibenzo [d,g] [1,3,6,2]dioxathiaphosphocin 6-sulphide

Abstract 2,10 Dichloro 6-(2,3 dimethylphenoxy) dibenzo [d. g] [1,3.6,2] dioxathiaphosphocin 6-sulphide (C20H15Cl2O3PS) crystallizes in the triclinic system, P[unk] with a = 7.845(3) Å, b = 11.720(2) Å, c = 11.871(2) Å, a = 88.5(2)°, β = 73.6(2)°, γ = 89.1(2)°, V = 1046.7(4) Å3, Z = 2, D c = 1.489M gm−3, (MoKα ) = 0.71069 Å, F(000) = 480 and T = 293 K. The crystal structure was solved by direct methods and refined by full matrix least-squares method to a final R = 0.0345 for 2701 unique observed reflections [I ≥ 2σ(I)]. The chlorobenzene rings A & B which are at 68.8° to each other, are oriented respectively at 19.9° and 61.6° to the phenyl ring and both are at 36.5° to the best plane of the heterocyclic ring. The heterocyclic ring adopts a distorted boat chair conformation.