Synthesis of novel pyrazole-fused heterocycles, i.e., dihydro-1H- or 2H-oxepino[3,2-c]pyrazoles (6 or 7) from 4-allyloxy-1H-pyrazoles (1) via combination of Claisen rearrangement and ring-closing metathesis (RCM) has been achieved. A suitable catalyst for the RCM of 5-allyl-4-allyloxy-1H-pyrazoles (4) was proved to be the Grubbs second generation catalyst (Grubbs2nd) to give the predicted RCM p...

One-pot and facile preparations of 6-(2-hydroxy-5-R-benzoyl)-4-methyl-2-R1- pyrazolo[3,4-b]pyridines 4a-o are described, using the reaction of 3-formyl chromones 1 with 5-amino-1-R1-pyrazoles 2. An enamine-intermediate 2-ethyloxy-6-R-3-(3-methyl-1- phenylpyrazol-5-ylaminomethylene)chroman-4-one 3 was isolated at lower temperatures. Acyloxy-derivatives 5 of compounds 4 were obtained by acylation...

The new 3,5-(substituted) pyrazoles and isoxazoles were prepared by reaction of (N'(1)E, N'(3)E)- N'(1), N'(3)-bis (3,4,5-substitutedbenzylidene)malonohydrazide with hydrazine hydrate and hydroxylamine hydrochloride respectively under solvothermal conditions involving an ecofriendly method without any environmental pollution, the yield are in the range of 75-96%. The structure of the new compou...

The vaporization enthalpies of 1-methyl-, 1-ethyl-, 1-phenyl-, and 1-benzylimidazole, 1-methyl- and 1-phenylpyrazole, and trans-azobenzene are evaluated by correlation-gas chromatography (C-GC) using a variety of azines and diazines as standards. The vaporization enthalpies obtained by C-GC when compared to literature values are approximately 14 kJ·mol(-1) smaller for the imidazoles and 6 kJ·mo...

Di & tri substituted imidazoles were prepared by condensing phenylglyoxal with different aryl aldehydes in presence of ammonium acetate and glacial acetic acid. All the di and tri substituted imidazoles were characterized by spectral analysis i.e. HNMR and Mass spectral data. All the synthetic compounds were screened for there anti-inflammatory and anti bacterial activity.

Direct arylation of most five-membered ring heterocycles are generally easily accessible and strongly favored at the ?-position using classical palladium-catalysis. Conversely, regioselective functionalization such concurrent ?-position remains currently very challenging. Herein, we report general conditions for direct pyrazoles, while C?H is free. By aryl bromides as source a judicious choice ...

A one-pot reaction between C2F5CH2NH2·HCl, NaNO2 and electron-deficient alkynes gives C2F5-substituted pyrazoles in excellent yields. The transformation smoothly proceeds in dichloromethane/water, tolerates the presence of air, and requires no purification of products by column chromatography. Mechanistically, C2F5CH2NH2·HCl and NaNO2 react first in water to generate C2F5CHN2, that participates...

The inhibitive effect of compound (1-acetyl-4, 5-dihydro-5-Bromophenyl-3-(thiophen-2yl) pyrazoles) on mild steel in 1M H2SO4 and 1M HCl was investigated by weight loss, Potentiodynamic polarization and electro chemical impidence studies. The synthesized compound of 1-acetyl-4, 5-dihydro-5-Bromophenyl-3-(thiophen-2yl) pyrazoles was characterized by FTIR, H NMR, C NMR and mass. The purity of the ...