In the title compound, C6H10N2O, the 2,3-dihydro-1H-pyrazole ring is approximately planar, with a maximum deviation of 0.013 (1) Å. Pairs of inter-molecular N - H⋯O hydrogen bonds link neighboring mol-ecules into dimers, generating R 2 2(8) ring motifs. These dimers are further linked into two-dimensional arrays parallel to the bc plane by inter-molecular N - H⋯O hydrogen bonds. The crystal structure is further stabilized by C - H⋯π inter-actions.

Sarveswari S

Department of Chemistry

School of Advanced Sciences

Vellore Campus

Vijayakumar V

Shahani T

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

Acta Crystallographica Section E Structure Reports Online

Organic and Medicinal Chemistry Letters

β-Keto esters from ketones and ethyl chloroformate: a rapid, general, efficient synthesis of pyrazolones and their antimicrobial, in silico and in vitro cytotoxicity studies

A series of β-keto esters were synthesized from heteroaryl esters and ethyl acetate using LiHMDS as base at -50 to -30 °C. The increase in yields of cross condensed product were observed and the percentage of self condensed product was reduced drastically by applying the suitable base (LiHMDS), solvent and the minimum amount of ethyl acetate. All these β-keto esters were characterized using 1H NMR, 13C NMR and mass spectral data. A plausible mechanism is also depicted to prove the formation of trans-esterified products. All the synthesized compounds were subjected to test for their cytotoxicity towards various cancer cell lines and also tested for their antimicrobial activity towards various bacterial and fungal strains and some of them were found to have promising activity. © 2012 Elsevier Ltd. All rights reserved.

Bioorganic & Medicinal Chemistry Letters

Simple, fast and efficient synthesis of β-keto esters from the esters of heteroaryl compounds, its antimicrobial study and cytotoxicity towards various cancer cell lines

In the title compound, C17H15FN2O 2, the essentially planar pyrazole ring [maximum deviation = 0.026 (1) Å] makes dihedral angles of 72.06 (7) and 33.05 (7)°, with the phenyl and fluorobenzene rings, respectively. The dihedral angle between the two sixmembered rings is 87.88 (7)°. In the crystal, intermolecular N -H⋯O and C -H⋯F hydrogen bonds link the molecules into layers lying parallel to the bc plane.

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

The asymmetric unit of the title compound, C 23H 23ClFN5O 2, contains two crystallographically independent mol-ecules. In one mol-ecule, the pyrazole ring makes dihedral angles of 43.93 (7) and 35.82 (7)°, respectively, with the fluoro- and chloro-substituted benzene rings, while the corresponding angles in the other mol-ecule are 52.26 (8) and 36.85 (7)°. The piperazine rings adopt chair conformations. In the crystal, adjacent mol-ecules are connected via inter-molecular N - H⋯O, C - H⋯F, C - H⋯N and C - H⋯O hydrogen bonds, forming a two-dimensional network parallel to the bc plane. The crystal structure is further stabilized by a weak π-π inter-action with a centroid-centroid distance of 3.6610 (8) Å and by C - H⋯π inter-actions. © Shahani et al. 2011.

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

The asymmetric unit of the title compound, C13H 16N2OS, contains two independent molecules (A and B). The pyrazole ring [maximum deviations = 0.0049 (17) Å in molecule A and 0.0112 (19) Å in molecule B] makes a dihedral angle of 70.23 (11) and 73.18 (12)° with the phenyl ring in molecules A and B, respectively. The isobutyl group in molecule B is disordered over two sets of sites with a ratio of refined occupancies of 0.858 (5):0.142 (5). In the crystal, molecules A and B are linked via a pair of intermolecular N -H⋯O hydrogen bonds, generating an R 2 2(8) ring motif. These ring motifs are further linked into twodimensional arrays parallel to the bc plane by intermolecular N -H⋯O and weak C -H⋯S hydrogen bonds. The crystal is further stablized by weak π-π interactions [centroidcentroid distances = 3.5698 (13) and 3.5287 (12) Å].

3-Isobutyl-4-phenylsulfanyl-1H-pyrazol-5-ol

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.

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