Novel triazole-sulfonamide bearing pyrimidine moieties with carbonic anhydrase inhibitory action: Design, synthesis, computational and enzyme inhibition studies

Anticancer potential and structure activity studies of purine and pyrimidine derivatives: an updated review

Cancer is the world's leading cause of death impacting millions of lives globally. The increasing research over the past several decades has focused on the development of new anticancer drugs, but still cancer continues to be a global health challenge. Thus, several new alternative therapeutic strategies have been tried for the drug design and discovery. Purine and pyrimidine heterocyclic compounds have received attention recently due to their potential in targeting various cancers. It is evident from the recently published data over the last decade that incorporation of the purine and pyrimidine rings in the synthesized derivatives resulted in the development of potent anticancer molecules. This review presents synthetic strategies encompassing several examples of recently developed purine and pyrimidine-containing compounds as anticancer agents. In addition, their structure-activity relationships are represented in the schemes indicating the fragment or groups that are essential for the enhanced anticancer activities. Purine and pyrimidines combined with other heterocyclic compounds have resulted in many novel anticancer molecules that address the challenges of drug resistance. The purine and pyrimidine derivatives showed significantly enhanced anticancer activities against targeted receptor proteins with numerous compounds with an IC50 value in the nanomolar range. The review will support medicinal chemists and contribute in progression and development of synthesis of more potent chemotherapeutic drug candidates to mitigate the burden of this dreadful disease.

Novel synthesis of new triazine sulfonamides with antitumor, anti-microbial and anti-SARS-CoV-2 activities

Novel approach for synthesizing triazine sulfonamide derivatives is accomplished via reacting the sulfaguanidine derivatives with N-cyanodithioiminocarbonate. Further reaction of the novel triazine sulfonamide analogues with various secondary amines and anilines generated various substituted triazine sulfonamide analogues of promising broad-spectrum activities including anti-microbial, anti-tumor, and anti-viral properties. The in vitro anti-proliferative activities of most of the novel compounds were evaluated on the NCI-60 cell line panel. The antifungal and antibacterial activities of the compounds were also estimated. The anti-viral activity against SARS CoV-2 virus was performed using MTT cytotoxicity assay to evaluate the half-maximal cytotoxic concentration (CC50) and inhibitory concentration 50 (IC50) of a representative compound from the novel triazine sulfonamide category. Compound 3a demonstrated potent antiviral activity against SARS-CoV-2 with IC50 = 2.378 µM as compared to the activity of the antiviral drug remdesivir (IC50 = 10.11 µM). Our results indicate that, upon optimization, these new triazine sulfonamides could potentially serve as novel antiviral drugs.

Design, synthesis and in silico insights of novel 1,2,3-triazole benzenesulfonamide derivatives as potential carbonic anhydrase IX and XII inhibitors with promising anticancer activity

Novel 1,2,3-triazole benzenesulfonamide derivatives were designed as inhibitors for the tumor- related hCA IX and XII isoforms. Most of the synthesized compounds showed good inhibitory activity against hCA IX and hCA XII isoforms. Compounds 4d, 5h and 6b, exhibited remarkable activity as hCA IX inhibitors, with Ki values in the range of 0.03 to 0.06 µM, more potent than AAZ. Additionally, compounds 5b and 6d, efficiently inhibited hCA XII isoform, with Ki value of 0.02 µM, respectively, similar to AAZ. Further investigation for those potent derivatives against MCF-7, Hep-3B and WI-38 cell lines was achieved. Compounds 4d and 6d exerted dual cytotoxic activity against MCF-7 and Hep-3B cell lines, with IC50 values of 3.35 & 2.12 µM against MCF-7 cell line and 1.72 & 1.56 µM against Hep-3B cell line, with high SI values ranged from 8.92 to 17.38 on both of the cell lines. Besides, they showed a high safety profile against normal human cell line, WI-38. Moreover, compound 5h had better cytotoxic effect on MCF-7 than the reference, DOX, with IC50 value of 4.02 µM. While, compounds 5b and 6b showed higher activity against Hep-3B if compared to the reference drug, 5-FU. From ADME study, compounds 4d, 5b, 6b and 6d obeyed Lipinski's rule of five, and they might be orally active derivatives, while, compound 5h exerted less oral bioavailability than the reference standard acetazolamide. Molecular docking and MDS studies predicted the binding mode and the stability of the target compounds inside hCA IX and hCA XII active sites, especially for compounds 5b and 6b.

Sulfonyl thiourea derivatives from 2-aminodiarylpyrimidines: In vitro and in silico evaluation as potential carbonic anhydrase I, II, IX, and XII inhibitors

A series of synthesized sulfonyl thiourea derivatives (7a-o) of substituted 2-amino-4,6-diarylpyrimidines (4a-o) exhibited the remarkable inhibitory activity against some the human carbonic anhydrases (hCAs), including hCA I, II, IX, and XII isoforms. The inhibitory efficacy of synthesized sulfonyl thiourea derivatives were experimentally validated by in vitro enzymatic assays. 7a (KI  = 46.14 nM), 7j (KI  = 48.92 nM), and 7m (KI  = 62.59 nM) (for isoform hCA I); 7f (KI  = 42.72 nM), 7i (KI  = 40.98 nM), and 7j (KI  = 33.40 nM) (for isoform hCA II); 7j (KI  = 228.5 nM), 7m (KI  = 195.4 nM), and 7n (KI  = 210.1 nM) (for isoform hCA IX); 7l (KI  = 116.9 nM), 7m (KI  = 118.8 nM), and 7n (KI  = 147.2 nM) (for isoform hCA XII) in comparison with KI values of 452.1, 327.3, 437.2, and 338.9 nM, respectively, of the standard drug AAZ. These compounds also had significantly more potent inhibitory action against cytosolic isoform hCA I and tumor-associated isoforms hCA IX and hCA XII. Furthermore, the potential inhibitory compounds were subjected to in silico screening for molecular docking and molecular dynamics simulations. The results of in vitro and in silico studies revealed that compounds 7a, 7j, and 7m were the most promising derivatives in this series due to their significant effects on studied hCA I, II, IX, and XII isoforms, respectively. The results showed that the sulfonyl thiourea moiety was accommodated deeply in the active site and interacted with the zinc ion in the receptors.

Discovery of novel benzenesulfonamides incorporating 1,2,3-triazole scaffold as carbonic anhydrase I, II, IX, and XII inhibitors

Sulfonamides are among the most promising potential inhibitors for carbonic anhydrases (CAs), which are pharmaceutically relevant targets for treating several disease conditions. Herein, a series of benzenesulfonamides bearing 1,2,3-triazole moiety as inhibitors of human (h) α-CAs (hCAs) were designed using the tail approach. The design method combines a benzenesulfonamide moiety with a tail of oxime and a zinc-binding group on a 1,2,3-triazole scaffold. Among the synthesized derivatives, the naphthyl (6m, K_I of 68.6 nM, S_I of 10.3), and methyl (6a, K_I of 56.3 nM, S_I of 11.7) derivatives (over hCA IX) and propyl (6c, K_I of 95.6 nM, S_I of 2.7), and pentyl (6d, K_I of 51.1 nM, S_I of 6.6) derivatives (over hCA XII) displayed a noticeable selectivity for isoforms hCA I and II, respectively. Meanwhile, derivative 6e displayed a potent inhibitory effect versus the cytosolic isoform hCA I (K_I of 47.8 nM) and tumor-associated isoforms hCA IX and XII (K_Is of 195.9 and 116.9 nM, respectively) compared with the reference drug acetazolamide (AAZ, K_Is of 451.8, 437.2, and 338.9 nM, respectively). Derivative 6b showed higher potency (K_I of 33.2 nM) than AAZ (K_I of 327.3 nM) towards another cytosolic isoform hCA II. Nevertheless, substituting the lipophilic large naphthyl tail to the 1,2,3-triazole linked benzenesulfonamides (6a-n) raised inhibitory effect versus hCA I and XII and selectivity towards hCA I and II isoforms over hCA IX. Evaluation of the cytotoxic potential of the synthesized derivatives was conducted in L929, MCF-7, and Hep-3B cell lines. Several compounds in the series demonstrated significant antiproliferative activity and minimal cytotoxicity. In the molecular docking study, the sulfonamide moiety interacted with the zinc-ion and neatly fit into the hCAs active sites. The extension of the tail was found to participate in diverse hydrophilic and hydrophobic interactions with adjacent amino acids, ultimately influencing the effectiveness and specificity of the derivatives.

Synthesis and Pharmacological Evaluation of Novel Triazole-Pyrimidine Hybrids as Potential Neuroprotective and Anti-neuroinflammatory Agents

OBJECTIVE

Neuroprotection is a precise target for the treatment of neurodegenerative diseases, ischemic stroke, and traumatic brain injury. Pyrimidine and its derivatives have been proven to use antiviral, anticancer, antioxidant, and antimicrobial activity prompting us to study the neuroprotection and anti-inflammatory activity of the triazole-pyrimidine hybrid on human microglia and neuronal cell model.

METHODS

A series of novel triazole-pyrimidine-based compounds were designed, synthesized and characterized by mass spectra, 1HNMR, 13CNMR, and a single X-Ray diffraction analysis. Further, the neuroprotective, anti-neuroinflammatory activity was evaluated by cell viability assay (MTT), Elisa, qRT-PCR, western blotting, and molecular docking.

RESULTS

The molecular results revealed that triazole-pyrimidine hybrid compounds have promising neuroprotective and anti-inflammatory properties. Among the 14 synthesized compounds, ZA3-ZA5, ZB2-ZB6, and intermediate S5 showed significant anti-neuroinflammatory properties through inhibition of nitric oxide (NO) and tumor necrosis factor-α (TNF-α) production in LPS-stimulated human microglia cells. From 14 compounds, six (ZA2 to ZA6 and intermediate S5) exhibited promising neuroprotective activity by reduced expression of the endoplasmic reticulum (ER) chaperone, BIP, and apoptosis marker cleaved caspase-3 in human neuronal cells. Also, a molecular docking study showed that lead compounds have favorable interaction with active residues of ATF4 and NF-kB proteins.

CONCLUSION

The possible mechanism of action was observed through the inhibition of ER stress, apoptosis, and the NF-kB inflammatory pathway. Thus, our study strongly indicates that the novel scaffolds of triazole-pyrimidine-based compounds can potentially be developed as neuroprotective and anti-neuroinflammatory agents.

Synthesis and anticancer activity of new benzensulfonamides incorporating s-triazines as cyclic linkers for inhibition of carbonic anhydrase IX

Limited presence of hCA IX in normal physiological tissues and their overexpression only in solid hypoxic tumors made this isoform excellent possible target for developing new anticancer agents. We reported designing and synthesis of two novel series of benzenesulfonamides derivatives as hCA IX inhibitors bearing rigid cyclic linkers (1,3,5-dihydrotriazine in series A and 1,3,5-triazine in series B) in replace of traditional linear linkers. Also, novel cyanoethenyl spacer was assembled next to the 1,3,5-triazine linker in series B. Target compounds of series (A) and (B) were screened against four hCA isoforms. Human CA IX efficiently inhibited in series (A) by compound 5a (K_I = 134.8 nM). Meanwhile, in series (B) the most active inhibitor was 12i (K_I = 38.8 nM). US-NCI protocol was followed to evaluate the anticancer activity of target compounds against panel of sixty cancer cell lines. Compound 12d, exposed the best activity towards breast cancer (MDA-MB-468) with GI% = 62%. The most active analogues, 12d and 12i were further screened for in vitro cytotoxic activity under hypoxic condition against breast cancer (MDA-MB-468) (IC₅₀ = 3.99 ± 0.21 and 1.48 ± 0.08 µM, respectively) and leukemia (CCRF-CM) cell line (IC₅₀ = 4.51 ± 0.24 and 9.83 ± 0.52 µM, respectively). In addition, 12d arrested breast cancer MDA-MB-468 cell cycle in G0-G1 and S phases and induced its apoptosis which indicated by increasing the level of cleaved caspases 3 and 9. Molecular docking was performed for selected analogues to understand their biological alterations. This study revealed that insertion of 1,3,5-triazines as cyclic linkers enhanced the significant anticancer and hCA IX inhibition activity of benzenesulfonamides.

Discovery of novel drugs for Chagas disease: is carbonic anhydrase a target for antiprotozoal drugs?

INTRODUCTION

Carbonic anhydrase (CA) arose significant interest as a potential new target for Chagas disease since its discovery in Trypanosoma cruzi in 2013. Benznidazole and Nifurtimox have been used for Chagas disease treatment for 60 years despite all efforts done for obtaining more efficient treatments, acting in the acute and chronic phases of illness, with fewer side effects and resistance induction.

AREAS COVERED

We discuss the positive and negative aspects of T. cruzi CA (TcCA) studies as a target for developing new drugs. The current research discoveries and the classes of TcCA inhibitors are reviewed. The sulfonamides and their derivatives are the main inhibitor classes, but hydroxamates and the thiols, were investigated too. These compounds inhibited the growth of the evolutive forms of the parasite. A comparative analysis was done with CAs from other Trypanosomatids and protozoans.

EXPERT OPINION

The search for new targets and drugs is a significant challenge worldwide, and TcCA is a potential candidate for developing new drugs. Several studied inhibitors were active against Trypanosoma cruzi, but their penetration and toxicity problems emerged. New approaches are in progress to obtain inhibitors with desired properties, allowing further steps such as tests using an adequate animal model and subsequent developments for the preclinical testing.

Click chemistry-based synthesis of new benzenesulfonamide derivatives bearing triazole ring as selective carbonic anhydrase II inhibitors

A series of 1,2,3-triazol-1-ylbenzenesulfonamide derivatives was designed, synthesized and their ability to inhibit several carbonic anhydrase isoforms was evaluated. The basis of our design is to hybridize the benzenesulfonamide moiety widely used as a zinc-binding group, a triazole ring as spacer with a tail of different substituted aryl moieties. The synthesis of these compounds was achieved using Cu(I)-mediated click chemistry between the azide containing the benzenesulfonamide pharmacophore and various aryl acetylenes or 1,6-heptadiyne through copper-catalyzed [3+2] cycloaddition reaction. The ability the new derivatives to inhibit four human carbonic anhydrase isoforms hCA I, II, IX, and XII was evaluated. All the compounds exhibited good potency and high selectivity towards isoforms hCA I and II more than isoforms hCA IX and XII, especially for the derivatives 3c and 3j that displayed Ki of 2.8 and 3.8 nM against hCA II and a high hCA II selectivity ratio ranging from 77.6 to 3571.4 over other isoforms. All the compounds were docked in the active site of the downloaded hCA II active site and their binding pattern confirmed their significant activity by interacting of the sulfonamide moiety with zinc ion in the active site, in addition to its hydrogen bond interaction with Thr199 and Thr200. All the above-mentioned findings pointed out towards the promising activity of the synthesized series that can be presented as a new scaffold to be further optimized as selective antiglaucoma drugs.

Development of spiro-3-indolin-2-one containing compounds of antiproliferative and anti-SARS-CoV-2 properties

A series of 1″-(alkylsulfonyl)-dispiro[indoline-3,2'-pyrrolidine-3',3″-piperidine]-2,4″-diones 6a‒o has been synthesized through regioselective multi-component azomethine dipolar cycloaddition reaction of 1-(alkylsulfonyl)-3,5-bis(ylidene)-piperidin-4-ones 3a‒h. X-ray diffraction studies (6b‒d,h) confirmed the structures. The majority of the synthesized analogs reveal promising antiproliferation properties against a variety of human cancer cell lines (MCF7, HCT116, A431 and PaCa2) with good selectivity index towards normal cell (RPE1). Some of the synthesized agents exhibit potent inhibitory properties against the tested cell lines with higher efficacies than the standard references (sunitinib and 5-fluorouracil). Compound 6m is the most potent. Multi-targeted inhibitory properties against EGFR and VEGFR-2 have been observed for the synthesized agents. Flow cytometry supports the antiproliferation properties and shows the tested agents as apoptosis and necrosis forming. Vero cell viral infection model demonstrates the anti-SARS-CoV-2 properties of the synthesized agents. Compound 6f is the most promising (about 3.3 and 4.8 times the potency of the standard references, chloroquine and hydroxychloroquine). QSAR models explain and support the observed biological properties.

Design, synthesis, and biological activity of novel dithiocarbamate-methylsulfonyl hybrids as carbonic anhydrase inhibitors

Carbonic anhydrase (CA) enzymes are involved in many physiological events. These enzymes, which contain Zn²⁺ in their structure, can be easily inhibited by dithiocarbamate compounds. In addition, CA enzyme inhibitory activities are known in groups such as sulfonamide and methylsulfonyl. For this purpose, in this study, a series of 23 new dithiocarbamate-methylsulfonyl derivatives were synthesized and their CA enzyme inhibitory activities were investigated. The inhibition potentials of the obtained compounds against the human CA I and CA II enzymes were investigated by the in vitro enzyme isolation method. It is seen that the compounds show activity at the nanomolar level. Molecular docking studies of the compounds were carried out by in silico methods. The poses of compounds 2a, 2e, 2o, and 2t are presented.

New bis- and tetrakis-1,2,3-triazole derivatives: Synthesis, DNA cleavage, molecular docking, antimicrobial, antioxidant activity and acid dissociation constants

In this study, a series of bis- and tetrakis-1,2,3-triazole derivatives were synthesized using copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry in 73-95% yield. The bis- and tetrakis-1,2,3-triazoles exhibited significant DNA cleavage activity while the tetrakis-1,2,3-triazole analog 6g completely degraded the plasmid DNA. Molecular docking simulations suggest that compound 6g acts as minor groove binder of DNA by binding through several noncovalent interactions with base pairs. All bis- and tetrakis-1,2,3-triazole derivatives were screened for antibacterial activity against E. coli, B. cereus, S. aureus, P. aeruginosa, E. hirae, L. pneumophila subsp. pneumophila strains and antifungal activity against microfungus C. albicans and C. tropicalis strains. Compound 4d exhibited the best antibacterial activity among bis-1,2,3-triazoles against E. coli and E. hirae, while 6c exhibited the best antibacterial activity among tetrakis-1,2,3-triazoles against E. hirae. Furthermore, the best antifungal activity against C. albicans and C. tropicalis was reported for the compound 5, while 6d displayed the best antifungal activity against C. tropicalis and C. albicans. Reasonable iron chelating activities and DPPH radical scavenging abilities were found for some of the compounds. Finally, the acid dissociation constants (pK_a) of the bis-1,2,3-triazoles were also determined with the help of HYPERQUAD program using the data obtained from potentiometric titrations. The reported data here concludes that the bis- and tetrakis-1,2,3-triazoles are important cores that should be considered for further development of especially new anticancer agents acting through the DNA cleavage activity.

Dual targeting of acetylcholinesterase and tau aggregation: Design, synthesis and evaluation of multifunctional deoxyvasicinone analogues for Alzheimer's disease

Development of multitargeted ligands have demonstrated remarkable efficiency as potential therapeutics for Alzheimer's disease (AD). Herein, we reported a new series of deoxyvasicinone analogues as dual inhibitor of acetylcholinesterase (AChE) and tau aggregation that function as multitargeted ligands for AD. All the multitargeted ligands 11(a-j) and 15(a-g) were designed, synthesized, and validated by ¹HNMR, ¹³CNMR and mass spectrometry. All the synthesized compounds 11(a-j) and 15(a-g) were screened for their ability to inhibit AChE, BACE1, amyloid fibrillation, α-syn aggregation, and tau aggregation. All the screened compounds possessed weak inhibition of BACE-1, Aβ₄₂ and α-syn aggregation. However, several compounds were identified as potential hits in the AChE inhibitory screening assay and cellular tau aggregation screening. Among all compounds, 11f remarkably inhibited AChE activity and cellular tau oligomerization at single-dose screening (10 µM). Moreover, 11f displayed a half-maximal inhibitory concentration (IC₅₀) value of 0.91 ± 0.05 µM and half-maximal effective concentration (EC₅₀) value of 3.83 ± 0.51 µM for the inhibition of AChE and cellular tau oligomerization, respectively. In addition, the neuroprotective effect of 11f was determined in tau-expressing SH-SY5Y cells incubated with Aβ oligomers. These findings highlighted the potential of 11f to function as a multifunctional ligand for the development of promising anti-AD drugs.