In the title compound, C22H17ClFN3O 2S, the pyrazole ring is approximately planar with a maximum deviation of 0.001 (4) Å and makes dihedral angles of 4.95 (19), 35.78 (18) and 54.73 (18)° with the thia-zole, fluoro-benzene and chloro-benzene rings, respectively. In the crystal, inter-molecular C - H⋯O hydrogen bonds link the mol-ecules into chains along the a axis.

Sarveswari S

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Vijayakumar V

Loh W.-S

Fun H.-K

Ragavan R.V

Fulltext

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Ethyl 2-[5-(4-chloro-phen-yl)-1-(4-fluoro-phen-yl)-1H-pyrazol-3-yl]-4-methyl-thia-zole-5-carboxyl-ate.

Acta Crystallographica Section E Structure Reports Online

The asymmetric unit of the title compound, C11H 12N2O, consists of two crystallographically independent molecules (A and B) with similar geometries. Both molecules exist in a keto form, the C=O bond length being 1.286 (2) Å in A and 1.283 (2) Å in B. The dihedral angles between the pyrazole ring and the attached phenyl ring are 43.28 (12) and 46.88 (11)°, respectively, for A and B. The ethyl unit in molecule B is disordered over two positions with a siteoccupancy ratio of 0.508 (5):0.492 (5). In the crystal, each of the independent molecules forms a centrosymmetric dimer with an R 2 2(8) ring motif through a pair of N -H⋯O hydrogen bonds. These dimers are further connected into a threedimensional network by intermolecular N -H⋯O and C -H⋯O hydrogen bonds. Intermolecular C -H⋯π interactions are also present.

5-Ethyl-4-phenyl-1H-pyrazol-3(2H)-one

The asymmetric unit of the title compound, C10H 10N2O, contains two crystallographically independent molecules with similar geometries, which exist in the keto form. The C=O bond lengths are 1.2878 (12) Åin molecule A and 1.2890 (12) Åin molecule B, indicating that the compound undergoes enol-to-keto tautomerism during the crystallization process. In molecule A, the pyrazole ring is approximately planar [maximum deviation = 0.007 (1) Å] and forms a dihedral angle of 36.67 (6)° with the attached phenyl ring. In molecule B, the dihedral angle formed between the pyrazole ring [maximum deviation = 0.017 (1) Å] and the phenyl ring is 41.19 (6)°. In the crystal, intermolecular N - H⋯O hydrogen bonds link neighbouring molecules into dimers generating R 22(8) ring motifs. These dimers are linked into ribbons along [101] via intermolecular N - H⋯O hydrogen bonds, forming R 42(10) ring motifs.

4-Methyl-5-phenyl-1H-pyrazol-3(2H)-one

The title compound, C13H16N2O 3S, consists of two crystallographically independent molecules with similar geometries and exists in a keto form, the C=O bond lengths being 1.267 (2) and 1.254 (2) Å. In both molecules, the pyrazole rings are approximately planar, with maximum deviations of 0.017 (2) and 0.010 (2) Å, and the dihedral angles between the pyrazole and phenyl rings are 83.63 (11) and 70.07 (12)°. In one molecule, an intra-molecular C - H⋯O hydrogen bond with an S(6) ring motif is observed. In the crystal, inter-molecular N - H⋯O and C - H⋯O hydrogen bonds link the molecules into two-dimensional networks parallel to the ab plane.

5-Isobutyl-4-phenylsulfonyl-1H-pyrazol-3(2H)-one

In the title compound, C28H22ClFN6O 2, the piperazine ring adopts a chair conformation and the least-squares plane through the four coplanar atoms forms dihedral angles of 69.37 (13) and 56.56 (12)°, respectively, with the pyrazole and cyano-phenyl rings. The dihedral angles formed between the pyrazole and the attached fluoro- and chloro-phenyl rings are 34.16 (10) and 73.27 (12)°, respectively. In the crystal, inter-molecular N - H⋯O, C - H⋯N and C - H⋯O hydrogen bonds link the molecules into sheets parallel to the ac plane.

4-{[5-(4-Chlorophenyl)-1-(4-fluorophenyl)-1H-pyrazol-3-yl]carbonyl}-N-(4-cyanophenyl)piperazine-1-carboxamide

Novel 1,5-diaryl pyrazole derivatives viz. 5-(4-chlorophenyl)-1-(4-fluorophenyl)-1H-pyrazole-3-carboxamides (2a-e, 3, 3a-f), 2-(5-(4-chlorophenyl)-1-(4-fluorophenyl)-1H-pyrazole-3-yl)thiazoles (6a-c,7, 8, 9a-c, 10, 11) were synthesized by varying the active part (amide group) of pyrazole, characterized using IR, (1)H NMR, mass spectral data and screened for their antibacterial activity against Escherichia coli (ATTC-25922), Staphylococcus aureus (ATTC-25923), Pseudomonas aeruginosa (ATTC-27853), Klebsiella pneumonia. Similarly all these compounds were screened for their antifungal activity against Aspergillus flavus (NCIM No. 524), Aspergillus fumigates (NCIM No. 902), Penicillium marneffei and Trichophyton mentagrophytes. Interestingly all the synthesized compounds exhibited good antibacterial (except 2a-c, 8, 9a) and antifungal activity (except 2a-c, 6a, 8, 9a).

European Journal of Medicinal Chemistry

Synthesis and antimicrobial activities of novel 1,5-diaryl pyrazoles

α-Oxy/thio substituted-β-keto esters were synthesized through an efficient cross-Claisen condensation of aryl oxy/thio acetic acid ethyl esters with acid chlorides, then it is converted in situ into 4-oxy/thio substituted-1H-pyrazol-5(4H)-ones by the addition of hydrazine or hydrazine derivatives and screened for their antibacterial, antifungal activities. © 2009 Elsevier Masson SAS. All rights reserved.

Synthesis of some novel bioactive 4-oxy/thio substituted-1H-pyrazol-5(4H)-ones via efficient cross-Claisen condensation

Acta Crystallographica Section D Biological Crystallography

Structure validation in chemical crystallography

<jats:p>An account is given of the development of the<jats:italic>SHELX</jats:italic>system of computer programs from<jats:italic>SHELX</jats:italic>-76 to the present day. In addition to identifying useful innovations that have come into general use through their implementation in<jats:italic>SHELX</jats:italic>, a critical analysis is presented of the less-successful features, missed opportunities and desirable improvements for future releases of the software. An attempt is made to understand how a program originally designed for photographic intensity data, punched cards and computers over 10000 times slower than an average modern personal computer has managed to survive for so long.<jats:italic>SHELXL</jats:italic>is the most widely used program for small-molecule refinement and<jats:italic>SHELXS</jats:italic>and<jats:italic>SHELXD</jats:italic>are often employed for structure solution despite the availability of objectively superior programs.<jats:italic>SHELXL</jats:italic>also finds a niche for the refinement of macromolecules against high-resolution or twinned data;<jats:italic>SHELXPRO</jats:italic>acts as an interface for macromolecular applications.<jats:italic>SHELXC</jats:italic>,<jats:italic>SHELXD</jats:italic>and<jats:italic>SHELXE</jats:italic>are proving useful for the experimental phasing of macromolecules, especially because they are fast and robust and so are often employed in pipelines for<jats:italic>high-throughput</jats:italic>phasing. This paper could serve as a general literature citation when one or more of the open-source<jats:italic>SHELX</jats:italic>programs (and the Bruker AXS version<jats:italic>SHELXTL</jats:italic>) are employed in the course of a crystal-structure determination.</jats:p>

Journal	Acta Crystallographica Section E Structure Reports Online
Publisher	International Union of Crystallography (IUCr)
ISSN	16005368
Open Access	No