3(5)-Phenyl-1H-pyrazoles are employed in this study to develop highly efficient organic crystalline solids with deep-blue ESIPT fluorescence as well as provide novel experimental insight into the mechanism of ESIPT fluorescence and generate an intriguing fluorescence "ON/OFF" switching.

5-Hydroxy-3-oxopent-4-enoic acid esters can be efficiently transformed into the stable bis-potassium salts of the corresponding 5-hydroxy-3-oxopent-4-enoic acids, from which the sensitive acids are released in situ, the latter being converted into substituted 4-hydroxy-2H-pyran-2-ones, pyrazoles and isoxazoles under mild conditions; the efficiency of this method is demonstrated by the first syn...

Ethyl diazoacetate (EDA), which is easily prepared from ethyl glycinate and NaNO2, reacts in situ with alkynes a water micelle environment without organic solvent to form pyrazoles. The reaction pH dependent, as the presence of protic catalysis (H2SO4 4 %, 3.5) mixture 3,5- 4,5-disubstituted pyrazoles was obtained, while, at 5.5, only 3,5-disubstituted isomer obtained. surfactant TPGS-750-M cru...

Chromones, six-membered oxygen heterocycles, and pyrazoles, five-membered two-adjacent-nitrogen-containing heterocycles, represent two important classes of biologically active compounds. Certain derivatives of these scaffolds play an important role in medicinal chemistry and have been extensively used as versatile building blocks in organic synthesis. In this context, we will discuss the most r...

A quantitative structure activity relationship (QSAR) study on tetrasubstituted pyrazoles as high affinity ligands for the estrogen receptor (both ERα and ERβ subtypes) have been performed using various combinations of hydrophobic (MlogP), steric (MR) and electronic (Xeq) descriptors. The regression analysis of the data has shown better results in multiparametric regressions upon introduction o...

Enantiomeric-enriched ferrocene-modified pyrazoles were synthesized via the reaction of the ferrocene alcohol, (S)-FcCH(OH)CH₃ (Fc = ferrocenyl), with various pyrazoles in acidic conditions at room temperature within several minutes. X-ray structural data for racemic (R,S)-1N-(3,5-dimethyl pyrazolyl)ethyl ferrocene (1) and its (S)-enantiomer (S)-1 were determined. A series of racemic pyrazolyla...

A facile and convenient synthesis of some novel hydrazones, schiff's base and pyrazoles from thieno[2,3-b]thiophene derivatives 1 have been achieved in high yields assisted by microwave and classical methods. The structures of all the title compounds have been elucidated by elemental analysis, IR, MS, (1)H-NMR and (13)C-NMR. Generally, these findings represent a new class of sulfur and nitrogen...