Progress in Pyrazole Chemistry

Synthesis of some 1-aryl-3,5-disubstituted-pyrazoles by N-arylation of 3,5-disubstituted-pyrazoles with 4-fluoro and 2-fluoronitrobenzene under microwave irradiation and classical heating

“…The compounds were analysed for C, H and N. The results were within 0.4% of the calculated theoretic values. The ratio of the regioisomers has been calculated through 1 H NMR experiments, especially from the integration of the C5-CH3 (α) and C3-CH3 (β) proton.…”

“…Indeed, unsymmetrical 1,3-diketones generally yield a mixture of two regioisomers in a ratio which depends on the nature of 1,3-diketones. 1 Moreover and according to some authors, this condensation leads to the formation of the undesired isomer as a major component. [2][3][4] Thereafter, direct substitution of N-nonsubstituted pyrazoles under previous reported conditions [5][6][7][8] such as K 2 CO 3 /DMF, K 2 CO 3 /DMSO, KOH/Bu 4 NBr, KOtBu and NaH/THF provide another powerful method for synthesis of N-arylpyrazoles.…”

Determination of Metoclopramide Hydrochloride in Pharmaceutical Formulations Using Three Different Spectrophotometric Methods

“…The reaction mixture was maintained under the condenser for 1 hr. A crystalline deposited precipitate was separated and washed with diethyl ether several times [49]. A Stock solution of DPP (1.7 × 10 -2 M) was prepared by dissolving 2.0 g of pure material in 0.3 M NaOH, then complete to 500 mL in a volumetric flask with the same solvent.…”

Synthesis of Nitriles – Synthesis of 4-Cyano Pyrazole, 5-Aminopyrazole Derivatives and the Deamination of 5-Aminopyrazole Derivatives

“…The 5-aminopyrazole system represents an important hetero-cyclic compound having considerable interest due their long history of applications in the pharmaceutical and agrochemical industries [1][2][3][4].…”