16619-60-6Relevant articles and documents
Synthesis of new pyrazoline-nucleoside analogue derivatives
Azouz,Lammara,Benallia,Guenane
, p. 294 - 305 (2013)
In this work, a synthesis of pyrazoline nucleosides analogues is presented, using the stereospecific sodium salt glycosylation procedure. In the first step, chalcones were prepared using Claisen Schmidt reaction by reacting benzaldehyde with enolizable ketones in ethanolic NaOH solutions. Next, these chalcones were immediately reacted with hydrazine hydrochloridein the presence of dry methanol to obtain the corresponding 2-pyrazolines. Finally, the coupling of the pyrazolines with 1-chloro-arabinofuranose leads to different β-nucleosides as the major product (13-17) in good yields. The structures of these derivatives were characterized by infrared and 1HNMR spectroscopy and mass spectrometry.
Development of 5-(Aryl)-3-phenyl-1H-pyrazole Derivatives as Potent Antimicrobial Compounds
Nagendra Chowdary,Umashankara,Dinesh,Girish,Ramesha Baba
, p. 45 - 50 (2018/12/11)
A series of 16 chalcone compounds were synthesized by Claisen-Schmidt condensation of various aldehydes with acetophenone using KOH as a base in ethanol. The reaction affords the desired products in good yields. Then all the 16 compounds were converted into pyrazoles by treating with hydrazine hydrate in ethanol under reflux condition. Both chalcones and pyrazoles were screened for their in vitro antibacterial (Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa) and antifungal (Aspergillus flavus, Chrysosporium keratinophilum and Candida albicans) activity. Biological activities of these compounds were compared with those of commercially available antibiotic ampicillin and antifungal agent miconazole. Pyrazoles were found to be most active and effective than corresponding chalcones for antimicrobial activity. Out of the 7 pyrazole compounds tested for antibacterial and antifungal activity, 5 compounds, 4h, 4j, 4l, 4m and 4n are turned out to be potent antimicrobial agents. Therefore these derivatives could serve as a highly promising molecules for further development.
Nano-TiO2: An efficient and reusable catalyst for the synthesis of 1,3,5-substituted pyrazoles
Akbari, Ali,Mirjalili, Bibi Fatemeh
, p. 119 - 123 (2016/07/15)
(Formula presented) A Nano-TiO2 is an efficient catalysis for the synthesis of 1,3,5-substituted pyrazoles via condensation of 1,3- diketones and hydrazines. Simple procedure, mild heating, solvent free, high yielding, and easy workup are some advantages of this protocol. The catalyst can be recovered easily and reused many times without significant loss in catalytic activity and selectivity.
