Synthesis of 1-(4-aminosulfonylphenyl)-3,5-diarylpyrazoline derivatives as potent antiinflammatory and antimicrobial agents

Discovery of Anticancer Agents from 2-Pyrazoline-Based Compounds

As nitrogen-containing five-membered heterocyclic structural units, the substituted pyrazole derivatives have a broad spectrum of pharmacological activities, especially 4,5-dihydro-1H-pyrazoles that also commonly known as 2-pyrazolines. Since 2010, considerable studies have been found that the 2-pyrazoline derivatives possess potent anticancer activities. In the present review, it covers the pyrazoline derivatives reported by literature from 2010 till date (2010-2019). This review aims to establish the relationship between the anticancer activities variation and different substituents introduced into a 2-pyrazoline core, which could provide important pharmacophore clues for the discovery of new anticancer agents containing 2-pyrazoline scaffold.

Design, synthesis, and carbonic anhydrase inhibition activity of benzenesulfonamide-linked novel pyrazoline derivatives

Carbonic anhydrases (CA, EC 4.2.1.1) are Zinc metalloenzymes and are present throughout most living organisms. Among the catalytically active isoforms are the cytosolic CA I and II, and tumor-associated CA IX and CA XII. The carbonic anhydrase (CA) inhibitory activities of newly synthesized pyrazoline-linked benzenesulfonamides 18-33 against human CA (hCA) isoforms I, II, IX, and XII were measured and compared with that of acetazolamide (AAZ), a standard inhibitor. Potent inhibitory activity against hCA I was exerted by compounds 18-25, with inhibition constant (KI) values of 87.8-244.1 nM, which were greater than that of AAZ (KI, 250.0 nM). Compounds 19, 21, 22, 29, 30, and 32 were proven to have inhibitory activities against hCA IX with KI values (5.5-37.0 nM) that were more effective than or nearly equal to that of AAZ (KI, 25.0 nM). Compounds 20-22, and 30 exerted potent inhibitory activities (KIs, 7.1-10.1 nM) against hCA XII, in comparison with AAZ (KI, 5.7 nM).

Synthesis, quantitative structure-property relationship study of novel fluorescence active 2-pyrazolines and application

A variety of fluorescence-active fluorinated pyrazolines 13-33 was synthesized in good yields through cyclocondensation reaction of propenones 1-9 with aryl hydrazines 10-12. Some of the synthesized compounds provided promising fluorescence properties with quantum yield (Φ) higher than that of quinine sulfate (standard reference). Quantitative structure-property relationship studies were undertaken supporting the exhibited fluorescence properties and estimating the parameters governing properties. Five synthesized fluorescence-active pyrazolines (13, 15, 18, 19 and 23) with variable Φ were selected for treating two types of paper sheets (Fabriano and Bible paper). These investigated fluorescence compounds, especially compounds 19 and 23, provide improvements in strength properties of paper sheets. Based on the observed performance they can be used as markers in security documents.

Synthesis and bioactivity studies on new 4-(3-(4-Substitutedphenyl)-3a,4-dihydro-3H-indeno[1,2-c]pyrazol-2-yl) benzenesulfonamides

A series of new 4-(3-(4-substitutedphenyl)-3a,4-dihydro-3H-indeno[1,2-c]pyrazol-2-yl) benzenesulfonamides (7-12) was synthesized starting from 2-(4-substitutedbenzylidene)-2,3-dihydro-1H-inden-1-one (1-6) and 4-hydrazinobenzenesulfonamide. The substituted benzaldehydes from which the key intermediate was prepared by introducing 2- or 4-substituents such as fluorine, hydroxy, methoxy, or the 3,4,5-trimethoxy moieties. The compounds were tested for their cytotoxicity, tumor-specificity and potential as carbonic anhydrase (CA, EC 4.2.1.1) inhibitors. The 3,4,5-trimethoxy and the 4-hydroxy derivatives showed interesting cytotoxic activities, which may be crucial for further anti-tumor activity studies, whereas some of these sulfonamides strongly inhibited both human (h) cytosolic isoforms hCA I and II.

Synthesis and carbonic anhydrase inhibitory activities of new thienyl-substituted pyrazoline benzenesulfonamides

A series of new thienyl-substituted pyrazoline benzenesulfonamides were synthesized and their carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activities were tested on the human (h) isoforms hCA I and hCA II. The inhibition constant (Ki) of these sulfonamides were in the range of 232.16-637.70 nM toward the slow cytosolic isozyme hCA I, and in the range of 342.07-455.80 nM toward hCA II. Many of these compounds showed comparable inhibition with the reference sulfonamide acetazolamide, a clinically used drug. As the sulfonamide CA inhibitors (CAIs) show many therapeutic uses, these derivatives represent interesting examples of a novel class of such derivatives.

Crystal structure of 4-[5-(4-fluorophenyl)-3-(4-hydroxyphenyl)-4,5-dihydropyrazol-1-yl] benzenesulfonamide, C21H18FN3O3S

C21H18FN3O3S, monoclinic, P 21 (no. 4), a = 11.6665(3) Å, b = 5.7483(2) Å, c = 14.7695(4) Å, α = 90°, β = 103.841(1)°, γ = 90°, V = 961.72(5) Å3, Z = 2, R gt (F) = 0.0340, wR ref (F 2 ) = 0.0852, T = 296(2) K.

Potentiation of ΔF508- and G551D-CFTR-Mediated Cl- Current by Novel Hydroxypyrazolines

The most common mutation of CFTR, affecting approximately 90% of CF patients, is a deletion of phenylalanine at position 508 (F508del, ΔF508). Misfolding of ΔF508-CFTR impairs both its trafficking to the plasma membrane and its chloride channel activity. To identify small molecules that can restore channel activity of ΔF508-CFTR, we synthesized and evaluated eighteen novel hydroxypyrazoline analogues as CFTR potentiators. To elucidate potentiation activities of hydroxypyrazolines for ΔF508-CFTR, CFTR activity was measured using a halide-sensitive YFP assay, Ussing chamber assay and patch-clamp technique. Compounds 7p, 7q and 7r exhibited excellent potentiation with EC₅₀ value <10 μM. Among the compounds, 7q (a novel CFTR potentiator, CP7q) showed the highest potentiation activity with EC₅₀ values of 0.88 ± 0.11 and 4.45 ± 0.31 μM for wild-type and ΔF508-CFTR, respectively. In addition, CP7q significantly potentiated chloride conductance of G551D-CFTR, a CFTR gating mutant; its maximal potentiation activity was 1.9 fold higher than the well-known CFTR potentiator genistein. Combination treatment with CP7q and VX-809, a corrector of ΔF508-CFTR, significantly enhanced functional rescue of ΔF508-CFTR compared with VX-809 alone. CP7q did not alter the cytosolic cAMP level and showed no cytotoxicity at the concentration showing maximum efficacy. The hydroxypyrazolines may be potential development candidates for drug therapy of cystic fibrosis.

Synthesis of some novel 4-arylidene pyrazoles as potential antimicrobial agents

BACKGROUND

Pyrazole and pyrazolone motifs are well known for their wide range of biological activities such as antimicrobial, anti-inflammatory, and antitumor activities. The incorporation of more than one pharmacophore in a single scaffold is a well known approach for the development of more potent drugs. In the present investigation, a series of differently substituted 4-arylidene pyrazole derivatives bearing pyrazole and pyrazolone pharmacophores in a single scaffold was synthesized.

RESULTS

The synthesis of novel 4-arylidene pyrazole compounds is achieved through Knovenagel condensation between 1,3-diaryl-4-formylpyrazoles and 3-methyl-1-phenyl-1H-pyrazol-5-(4H)-ones in good yields. All compounds were evaluated for their in vitro antimicrobial activity.

CONCLUSIONS

A series of 4-arylidene pyrazole derivatives was evaluated for their in vitro antimicrobial activity against two Gram-positive (Bacillus subtilis and Staphylococcus aureus) and two Gram-negative bacteria (Pseudomonas fluorescens and Escherichia coli), as well as two pathogenic fungal strains (Candida albicans and Saccharomyces cerevisiae). The majority of the compounds displayed excellent antimicrobial profile against the Gram-positive (B. subtilis and S. aureus), and some of them are even more potent than the reference drug ciprofloxacin.