Synthesis, characterization and carbonic anhydrase I and II inhibitory evaluation of new sulfonamide derivatives bearing dithiocarbamate

Chemistry of heterocycles as carbonic anhydrase inhibitors: A pathway to novel research in medicinal chemistry review

Nowadays, the scientific community has focused on dealing with different kinds of diseases by exploring the chemistry of various heterocycles as novel drugs. In this connection, medicinal chemists identified carbonic anhydrases (CA) as one of the biologically active targets for curing various diseases. The widespread distribution of these enzymes and the high degree of homology shared by the different isoforms offer substantial challenges to discovering potential drugs. Medicinal and synthetic organic chemists have been continuously involved in developing CA inhibitors. This review explored the chemistry of different heterocycles as CA inhibitors using the last 11 years of published research work. It provides a pathway for young researchers to further explore the chemistry of a variety of synthetic as well as natural heterocycles as CA inhibitors.

Synthesis, characterization and biological evaluation of pyrazole-based benzene sulfonamides as inhibitors of human carbonic anhydrase II, IX and XII

The aberrant level of the carbonic anhydrase isozymes is linked with various disorders which include glaucoma, epilepsy, altitude sickness and obesity. In the present study, a series of the pyrazole-based benzene sulfonamides derivatives (4a-4l) were designed, synthesized and evaluated as the inhibitors of the three isoforms of human carbonic anhydrases (hCAII, hCAIX and hCAXII). A number of the derivatives were found more active inhibitors than acetazolamide used as a standard against the human hCAII, hCAIX and hCAXII. Among the series, the compound 4k inhibited the hCAII to a submicromolar level presenting the IC₅₀ ± SEM concentration of 0.24 ± 0.18 μM, the inhibitor 4j reduced the activity of the hCAIX to the IC₅₀ ± SEM equals 0.15 ± 0.07 μM, whereas, the molecule 4g blocked the catalytic potential of the isozyme hCAXII with as low as IC₅₀ concentration of 0.12 ± 0.07 μM. In addition, compounds 4e and 4k were screened as the preferential inhibitors of the isoform hCAXII as compared to the hCAIX and hCAXII with half of the maximal concentrations of 0.75 ± 0.13 μM, and 0.24 ± 0.18 μM, respectively. Moreover, the compounds 4k, 4j and 4g were docked inside the active pocket of the crystallographic structure of the isoforms hCAXII, hCAIX and hCAXII, respectively. The docked inhibitors showed the binding interactions with the important amino acid residues such as Leu1198, Thr1199, His1094, and Phe1131 in hCAXII isozyme; residues Val121, Thr200, Pro203, and Gln71 in hCAIX; the amino acids Val119, Leu197, Gln89, and Asn64 in the case of hCAXII. In addition, structural geometries, reactivity descriptors, optimization energy and electronic parameters were calculated to predict the activity of the synthesized compounds.

A novel class of phenylpyrazolone-sulphonamides rigid synthetic anticancer molecules selectively inhibit the isoform IX of carbonic anhydrases guided by molecular docking and orbital analyses

All the previously reported phenylpyrazoles as carbonic anhydrase inhibitors (CAIs) were found to have small sizes and high levels of flexibility, and hence showed low selectivity profiles toward a particular isoform of CA. Herein, we report the development of a more rigid ring system bearing a sulfonamide hydrophilic head and a lipophilic tail to develop novel molecules that are suggested to have a better selectivity toward a special CA isoform. Accordingly, three novel sets of pyrano[2,3-c]pyrazoles attached with sulfonamide head and aryl hydrophobic tail were synthesized to enhance the selectivity toward a specific isoform of human carbonic anhydrases (hCAs). The impact of both attachments on the potency and selectivity has been extensively discussed in terms of in vitro cytotoxicity evaluation under hypoxic conditions, structure-activity relationship and carbonic anhydrase enzyme assay. All of the new candidates displayed good cytotoxic activities against breast and colorectal carcinomas. Results of the carbonic anhydrase enzyme assay demonstrated the preferential of compounds 22, 24 and 27 to inhibit the isoform IX of hCAs selectively. Wound-healing assay has also been performed and revealed the potential of 27 to decrease the wound closure percentage in MCF-7 cells. Molecular docking and molecular orbital analysis have finally been conducted. Results indicate the potential binding interactions of 24 and 27 with several crucial amino acids of the hCA IX.Communicated by Ramaswamy H. Sarma.

Sulfonamide-Derived Dithiocarbamate Gold(I) Complexes Induce the Apoptosis of Colon Cancer Cells by the Activation of Caspase 3 and Redox Imbalance

Two new families of dithiocarbamate gold(I) complexes derived from benzenesulfonamide with phosphine or carbene as ancillary ligands have been synthesized and characterized. In the screening of their in vitro activity on human colon carcinoma cells (Caco-2), we found that the more lipophilic complexes—those with the phosphine PPh₃—exhibited the highest anticancer activity whilst also displaying significant cancer cell selectivity. [Au(S₂CNHSO₂C₆H₅)(PPh₃)] (1) and [Au(S₂CNHSO₂-p-Me-C₆H₄)(IMePropargyl)] (8) produce cell death, probably by intrinsic apoptosis (mitochondrial membrane potential modification) and caspase 3 activation, causing cell cycle arrest in the G1 phase with p53 activation. Besides this, both complexes might act as multi-target anticancer drugs, as they inhibit the activity of the enzymes thioredoxin reductase (TrxR) and carbonic anhydrase (CA IX) with the alteration of the redox balance, and show a pro-oxidant effect.

The Versatility in the Applications of Dithiocarbamates

Dithiocarbamate ligands have the ability to form stable complexes with transition metals, and this chelating ability has been utilized in numerous applications. The complexes have also been used to synthesize other useful compounds. Here, the up-to-date applications of dithiocarbamate ligands and complexes are extensively discussed. Some of these are their use as enzyme inhibitor and treatment of HIV and other diseases. The application as anticancer, antimicrobial, medical imaging and anti-inflammatory agents is examined. Moreover, the application in the industry as vulcanization accelerator, froth flotation collector, antifouling, coatings, lubricant additives and sensors is discussed. The various ways in which they have been employed in synthesis of other compounds are highlighted. Finally, the agricultural uses and remediation of heavy metals via dithiocarbamate compounds are comprehensively discussed.

Synthesis, in vitro cytotoxicity and biological evaluation of twenty novel 1,3-benzenedisulfonyl piperazines as antiplatelet agents

In order to discover antiplatelet drug with novel structure and expand our research scope, total twenty 1,3-benzenedisulfonyl piperazines, were designed and synthesized. These target compounds were divided into two series, namely 4-methoxy-1,3-benzenedisulfonyl piperazines of series 1 and 4-ethoxy-1,3-benzenedisulfonyl piperazines of series 2. With adenosine diphosphate (ADP), arachidonic acid (AA) and collagen as inducers, respectively, the Born turbidimetric method was used to screen the antiplatelet activity in vitro of all target compounds at a concentration of 1.3 μM, with aspirin and picotamide as positive control drugs. And of which, the activities of five compounds for collagen were higher than both picotamide and aspirin. In ADP or AA channel, compounds with an inhibition rate greater than 33% were selected, and their corresponding IC₅₀ values were obtained. According to the IC₅₀, the in vitro activity of one compound for ADP was higher than picotamide, and for AA, two compounds were higher than two positive control drugs and other two compounds only higher than or equal to aspirin. The preliminary analysis of the structure-activity relationship of the target compounds involved in this study was completed. Further, eight compounds exhibiting higher activity in one or two test channels, were subjected to cytotoxicity test on mouse fibroblasts (L929) by CCK-8 method. The in vitro cytotoxicity of most test compounds showed less than or same to control drug picotamide at 10 μM, but at the higher concentration of 100 μM, merely two compounds exhibited higher cell survival rate than that of picotamide. In addition, compound N¹,N³-di(4-ethoxy-1,3-phenylenedisulfonyl)bis(1-(m-tolyl)piperazine), which is delivery activity in the three test channels, and another compound N¹,N³-di(4-methoxy-1,3-phenylenedisulfonyl)bis(1-(m-tolyl)piperazine), which has the lowest cytotoxic in vitro compound among series 1 and series 2, respectively, are found and selected for simulation analysis as two most likely to dock with the receptor P₂Y₁₂. Each of synthesized compounds in silico molecular property and ADME (absorption, distribution, metabolism and excretion) are predicted by using Molinspiration property engine v2018.10 and PreADMET online servers, respectively. Compared with other series of compounds in the previous stage, the two series compounds obtained after the introduction of piperazinyl have a similar in vitro activity.

Synthesis and pharmacological effects of novel benzenesulfonamides carrying benzamide moiety as carbonic anhydrase and acetylcholinesterase inhibitors

N -(1-(4-Methoxyphenyl)-3-oxo-3-((4-( N -(substituted)sulfamoyl)phenyl)amino)prop-1-en-1-yl)benzamides 3a – g were designed since sulfonamide and benzamide pharmacophores draw great attention in novel drug design due to their wide range of bioactivities including acetylcholinesterase (AChE) and human carbonic anhydrase I and II (hCA I and hCA II) inhibitory potencies. Structure elucidation of the compounds was carried out by 1H NMR, 13C NMR, and HRMS spectra. In vitro enzyme assays showed that the compounds had significant inhibitory potential against hCA I, hCA II, and AChE enzymes at nanomolar levels. Ki values were in the range of 4.07 ± 0.38 – 29.70 ± 3.18 nM for hCA I and 10.68 ± 0.98 – 37.16 ± 7.55 nM for hCA II while Ki values for AChE were in the range of 8.91 ± 1.65 – 34.02 ± 5.90 nM. The most potent inhibitors 3g (Ki = 4.07 ± 0.38 nM, hCA I), 3c (Ki = 10.68 ± 0.98 nM, hCA II ) , and 3f (Ki = 8.91 ± 1.65 nM, AChE) can be considered as lead compounds of this study with their promising bioactivity results. Secondary sulfonamides showed promising enzyme inhibitory effects on AChE while primary sulfonamide derivative was generally effective on hCA I and hCA II isoenzymes.