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5-Amino-1-phenyl-1H-pyrazole-4-carboxylic acid  [cached]
Muhammad Zia-ur-Rehman,Mark R. J. Elsegood,Nosheen Akbar,Rahman Shah Zaib Saleem
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808018394
Abstract: In the molecule of the title compound, C10H9N3O2, the pyrazole ring is approximately coplanar with the amino and carboxyl groups. The phenyl group is twisted by 48.13 (3)° relative to this plane. An intramolecular N—H...O hydrogen bond stabilizes the planar conformation of the molecule. The molecules are linked into two-dimensional sheets by two strong intermolecular N—H...N and O—H...O hydrogen bonds. The latter forms the classic carboxylic acid dimer motif.
Design; Synthesis and Antihypertensive activity of 4'-(2-{2-[(2-chloro-benzylidene)-amino]-phenyl}-5-nitro-benzoimidazol-1-ylmethyl)] biphenyl-2-carboxylic acid
M. C. Sharma,D.V. Kohli,Smita Sharma
International Journal of Advances in Pharmaceutical Sciences , 2011, DOI: 10.5138/174
Abstract: In the present study, a series of 4`-(2-{2-[(2-chloro-benzylidene)-amino]-phenyl}-5-nitro-benzoimidazol-1-ylmethyl)] biphenyl-2-carboxylic acid derivatives are synthesized by A one-step coupling of substituted benzimidazoles with biphenyl carboxylic moiety mediated by potassium carbonate is described. The biphenyl carboxylic moiety was prepared from 9-H-fluorenone and substituted benzimidazoles were synthesized from o-phenylenediamine with anthranilic acid. Keywords: Benzimidazoles, biphenyl-2-carboxylic acid, angiotensin II, hypertension
Isolation and Characterization of Bis (2 – Methoxyethyl) Phthalate and Hexashydro-1 3 – Dimethyl – 4 – Phenyl – 1h – Azepine 4 – Carboxylic Acid from the Root of Cissampelos Owariensis (P. Beauv)
OO Efiom
Nigerian Journal of Basic and Applied Sciences , 2010,
Abstract: The root of Cissampelos owariensis yielded two new additional compounds. These compounds were identified on the basis of spectroscopic analysis , here reported for the first time from the plant as bis (2-methoxy ethyl) phthalate and hexa hydro-1,3-dimethyl -4-phenyl-IH-azepine-4-carboxylic acid
6-Bromo-3-hydroxy-4-oxo-2-phenyl-4H-chromene-8-carboxylic acid dimethylformamide disolvate  [cached]
Hui-Liang Wen,Dan-Dan Chen,Chong-Bo Liu
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808019454
Abstract: In the title compound, C16H9BrO5·2C3H7NO, the chromene ring system is essentially planar. The two dimethylformamide solvent molecules are linked by intermolecular O—H...O hydrogen bonds to the 6-bromo-3-hydroxy-4-oxo-2-phenyl-4H-chromene-8-carboxylic acid molecules.
Synthetic Studies on Potent Marine Drugs: Synthesis and the Crystal Structure of 6-tert-butyl-4-phenyl-4H-chromene-2-carboxylic Acid  [PDF]
Hui-Jing Li,Jun-Li Wang,Rui Wang,Dong-Hui Luo,Yan-Chao Wu
Journal of Chemistry , 2013, DOI: 10.1155/2013/106908
Abstract: 4H-Chromene-2-carboxylic acid ester derivatives of renieramycin M might be of use for the structural-activity relationship studies of antitumor antibiotic tetrahydroisoquinoline natural products. Accordingly, 6-tert-butyl-4-phenyl-4H-chromene-2-carboxylic acid, one key intermediate, was synthesized via the condensation of (3E)-2-oxo-4-phenylbut-3-enoate methyl ester with 4-tert-butylphenol in the presence of AuCl3/3AgOTf (5?mol%), followed by cyclodehydration and aqueous hydrolysis. The product was unambiguously shown to the 4H-chromene-2-carboxylic acid by spectroscopy and X-ray crystallographic analysis. A packing diagram of the crystal structure shows that aromatic -stacking interactions and O–H?O hydrogen bond stabilize the structure in the solid. 1. Introduction Antitumor antibiotic renieramycin M (5, Figure 1) has been isolated from the marine sponge Xestospongia sp. in 2003 [1–3], which belongs to a family of tetrahydroisoquinoline natural products including ecteinascidin 743 (1, Et-743, yondelis, trabectedin), saframycin A (3), quinocarcin, and so forth [4–20]. These natural products show potent antitumor antibiotic activities, and Et-743 has received European approval for the treatment of soft tissue sarcoma and ovarian carcinoma [21]. The remarkable clinical results of Et-743 have stimulated the discovery of zalypsis (2) that is currently in advanced human clinical trials for treating Ewing’s sarcoma [22, 23]. It is noteworthy that quinoline-2-carboxylic acid amide derivative of saframycin A (QAD, 4) was shown to possess single-digit picomolar potency against three human sarcoma cell lines 100 times more potent than Et-743 [24]. On the other hand, the ester side chain structure of renieramycin M was also found to have a critical impact on its antitumor activities [25]. We envisioned that 4H-chromene-2-carboxylic acid ester derivatives of renieramycin M (6) might be of some use for the structural-activity relationship studies of this antitumor antibiotic marine natural product. Compound 6 was thought to be prepared from pentacyclic alcohol 7 by the selective acylation of the primary alcohol with 4H-chromene-2-carboxylic acids (8, Scheme 1). We have already reported the synthesis of compound 7 in our asymmetric total synthesis of renieramycin M and jorumycin [9]. Herein, we would like to report our endeavors on the synthesis of 4-phenyl-4H-chromene-2-carboxylic acid 8a. As the structure of this product might be possible 4-phenyl-2H-chromene-2-carboxylic acid 9a or 2-phenyl-2H-chromene-4-carboxylic acid 10a, X-ray crystallographic analysis was
Synthesis of new derivatives of 1-(3-aminophenyl)-4-benzoyl-5-phenyl-1H-pyrazole-3-carboxylic acid  [PDF]
RAHMI KASIMOGULLAR,BELMA ZENGIN,MAKBULE MADEN,SAMET MERT
Journal of the Serbian Chemical Society , 2010,
Abstract: 1-(3-Aminophenyl)-4-benzoyl-5-phenyl-1H-pyrazole-3-carboxylic acid (1) was synthesized according to the literature. 2-(3-Aminophenyl)-2,6-dihydro-3,4-diphenyl-7H-pyrazolo[3,4-d]pyridazin-7-one (5) was obtained by the cyclocondensation reaction of 1 with hydrazine hydrate. New pyrazole derivatives of compounds 1 and 5 were synthesized by their reaction with β-diketones, β-ketoesters, β-naphthol, phenol and various other reagents. The structures of the synthesized compounds were characterized by 1H-NMR, 13C-NMR, IR and mass spectroscopy, as well as elemental analysis.
Synthesis and biological evaluation of some new benzimidazoles derivatives 4'-{5-amino-2-[2-substituted-phenylamino)-phenyl-methyl]-benzimidazol-1 ylmethyl}-biphenyl-2-carboxylic acid: Nonpeptide angiotensin II receptor antagonists  [cached]
Mukesh C Sharma,Dharm V. Kohli,Smita Sharma
International Journal of Drug Delivery , 2011,
Abstract: A new series of non peptide angiotensin (A-II) receptor antagonist has been prepared. This N-(biphenyl methyl) imidazoles e.g. Some new 4'-{5-amino-2-[2-substituted-phenylamino)-phenyl-methyl]-benzimidazol-1-ylmethyl}-biphenyl-2-carboxylic acid derivatives were synthesized by 2-( α -hydroxy benzyl) benzimidazole was converted to 2-(α-bromo benzyl) benzimidazole by reacting with HBr and Anhydrous ZnCl2 Schiff bases react with biphenyl carboxylic acid with different substituents amino group cyclocondensation with appropriate reagents. Differ from the previously reported and related compounds in that they produce a potent hypertensive effect. The compounds synthesized were identified by 1H NMR, 13C NMR, FAB Mass and FT-IR spectroscopic techniques. All compounds studied in this work were screened for their antihypertensive activity by tail cuff method and direct method measurement of blood pressure. Keywords: Benzimidazoles; Biphenyl Carboxylic acid; Angiotension-II.
1-(4-tert-Butylbenzyl)-3-phenyl-1H-pyrazole-5-carboxylic acid  [cached]
Zheng Tang,Xiao-Ling Ding,Yong-Sheng Xie,Bao-Xiang Zhao
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809017000
Abstract: In the title compound, C21H22N2O2, the mean plane of the pyrazole ring makes dihedral angles of 18.80 (12) and 77.13 (5)°, respectively, with the mean planes of the phenyl and tert-butylbenzyl rings. The carboxylate group is inclined at 8.51 (14)° with respect to the pyrazole ring. The crystal structure displays intermolecular O—H...O hydrogen bonding, generating centrosymmetric dimers.
2-[3-Cyano-4-(2-methylpropoxy)phenyl]-4-methylthiazole-5-carboxylic acid pyridine solvate
Xiong Zhu,Yue Wang,Tao Lu
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809039002
Abstract: In the title compound, C16H16N2O3S·C5H5N, the benzene and thiazole rings of the Febuxostat [2-(3-cyano-4-isobutyloxy)phenyl-4-methyl-5-thiazolecarboxylic acid] molecule are almost coplanar [dihedral angle = 2.4 (1)°]. The carboxyl group is coplanar with the thiazole ring [O—C—C—C and O—C—C—S torsion angles of 0.7 (4) and 0.6 (3)°, respectively]. The pyridine molecule of crystallization is linked to the Febuxostat molecule through an O—H...N hydrogen bond. A weak π–π stacking interaction is observed between the benzene ring of the Febuxostat molecule and pyridine molecule, with a centroid–centroid distance of 3.7530 (18) .
3-Methyl-4-oxo-2-phenyl-4H-chromene-8-carboxylic acid  [cached]
Zhi Hong,Hua-Jiang Jiang,Yu-Guo Zhuang,Hai-Chang Guo
Acta Crystallographica Section E , 2008, DOI: 10.1107/s1600536808009732
Abstract: In the title compound, C17H12O4, the chromene unit is approximately planar, the maximum deviation from the mean plane being 0.0166 . The attached phenyl ring makes a dihedral angle of 53.2 (1)° with the fused ring system. The packing of the molecules in the crystal structure is governed by C—H...O and O—H...O hydrogen-bonding interactions.
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