Discovery of new sulfonamide-tethered 2-aryl-4-anilinoquinazolines as the first-in-class dual carbonic anhydrase and EGFR inhibitors.

In today's medical field, there is a growing trend of exploiting a single small molecule to target two different molecular targets concurrently. This approach is proving to be highly effective in fighting against cancer. The 4-anilinoquinazoline scaffold, known for its potential in cancer therapy and its effectiveness as a leading class of tyrosine kinase inhibitors, was employed to develop a novel series of anilinoquinazoline-sulfonamides (AQSs) (8a-d, 9a-f, and 10a-d) as dual inhibitors of the tumor-associated carbonic anhydrases (CA) IX/XII and EGFR. 2-(3-Methoxyphenyl)quinazoline bearing p-sulfanilamide 10b elicited superior hCA IX and XII inhibition in the low nanomolar range (KIs = 38.4 and 8.9 nM, respectively). Also, 10b shined as a potent and selective EGFR inhibitor, boasting an impressive IC50 value of 51.2 ±â€¯0.97 nM, surpassing the reference EGFR inhibitor Erlotinib (IC50 = 80 ±â€¯2.0 nM). Compound 10b exhibited broadest-spectrum antiproliferative activity against the NCI-tumor panel with a mean GI% value of 68 %. Of special interest, 10b demonstrated potent growth inhibition (GI% ≥ 80-97 %) toward cell lines reported to express high levels of EGFR belonging to renal, colon, breast, and lung cancers. Compound 10b's molecular docking in the CA IX/XII and EGFR active sites revealed binding modes that justify its potent enzyme inhibitory effects. Additionally, molecular dynamic simulations demonstrated strong and stable interactions of 10b with the binding sites of these targets.

Mitigating the resistance of MCF-7 cancer cells to Doxorubicin under hypoxic conditions with novel coumarin based carbonic anhydrase IX and XII inhibitors.

In the present study, the design and synthesis of novel coumarin derivatives 8a-h, 11a-d and 16a-c as potential selective inhibitors for the tumor associated human carbonic anhydrase isoforms (hCA IX and XII) was reported. All the newly synthesized derivatives showed potent to mild activity against the targeted CA IX (KI = 0.08-9.57 µM), with selectivity indices over CA I (SI = 2.0-21.9) and over CA II (SI = 1.1-15.7). They showed similar activities against CA XII (KI = 0.06-9.48 µM) with selectivity indices over CA I (SI = 1.4-21.2) and CA II (SI = 0.9-15.5). Compound 16b featuring sulfonamide function possessed promising inhibitory activities against the targeted isoforms CA IX and XII with KI values of 0.08 and 0.06 µM, respectively. Interestingly, it was found that using compound 16b at a nontoxic concentration as an adjuvant with Doxorubicin against MCF-7 cells enhanced the cytotoxicity under hypoxia by almost 3.5 folds; IC50 decreased from 25.74 to 7.43 µM. Therefore, compound 16b restored the cytotoxicity of Doxorubicin against MCF-7 cells under hypoxia, almost as normoxia. Furthermore, flow cytometry analysis of a combination treatment of compound 16b and Doxorubicin to the MCF7 cell line revealed an increase in cell cycle arrest at the G2/M phase and a more efficient apoptotic effect than Doxorubicin alone. Furthermore, compound 16b showed no cytotoxicity against normal breast MCF-10A cell line (IC50 = 296.25 µM).

Novel anti-inflammatory agents featuring phenoxy acetic acid moiety as a pharmacophore for selective COX-2 inhibitors: Synthesis, biological evaluation, histopathological examination and molecular modeling investigation.

Inflammation management presents a critical challenge in modern medicine, with nonsteroidal anti-inflammatory drugs (NSAIDs) being a widely used therapeutic option. However, their efficacy is often accompanied by significant gastrointestinal adverse effects, necessitating the exploration of safer alternatives, particularly through the investigation of cyclooxygenase-2 (COX-2) inhibitors. This study endeavors to address this imperative through the synthesis and evaluation of pyrazoline-phenoxyacetic acid derivatives. Among the synthesized compounds, 6a and 6c emerged as promising candidates, demonstrating potent COX-2 inhibition with IC50 values of 0.03 µM for both and selectivity index = 365.4 and 196.9, respectively. Furthermore, these compounds exhibited efficacy in mitigating formalin-induced edema in male Wistar rats, accompanied by favorable safety profiles upon histological examination of vital organs. Comprehensive safety assessments, including evaluation of creatinine, AST, and ALT enzymatic as well as troponin T and creatine kinase-MB levels, further reinforce the promising attributes of the synthetic candidates. Molecular docking studies endorsed by molecular dynamic simulations corroborate the biological findings, elucidating significant protein-ligand interactions at COX-2 active sites indicative of therapeutic potential.

Phthalimide-tethered isatins as novel poly(ADP-ribose) polymerase inhibitors: Design, synthesis, biological evaluations, and molecular modeling investigations.

Humanity is currently facing various diseases with significant mortality rates, particularly those associated with malignancies. Numerous enzymes and proteins have been identified as highly promising targets for the treatment of cancer. The poly(ADP-ribose) polymerases (PARPs) family comprises 17 members which are essential in DNA damage repair, allowing the survival of cancer cells. Unlike other PARP family members, PARP-1 and, to a lesser extent, PARP-2 show more than 90% activity in response to DNA damage. PARP-1 levels were shown to be elevated in various tumor cells, including breast, lung, ovarian, and prostate cancer and melanomas. Accordingly, novel series of phthalimide-tethered isatins (6a-n, 10a-e, and 11a-e) were synthesized as potential PARP-1 inhibitors endowed with anticancer activity. All the synthesized molecules were assessed against PARP-1, where compounds 6f and 10d showed nanomolar activities with IC50 = 15.56 ± 2.85 and 13.65 ± 1.42 nM, respectively. Also, the assessment of the antiproliferative effects of the synthesized isatins was conducted on four cancer cell lines: leukemia (K-562), liver (HepG2), and breast (MCF-7 and HCC1937) cancers. Superiorly, compounds 6f and 10d demonstrated submicromolar IC50 values against breast cancer MCF-7 (IC50 = 0.92 ± 0.18 and 0.67 ± 0.12 µM, respectively) and HCC1937 (IC50 = 0.88 ± 0.52 and 0.53 ± 0.11 µM, respectively) cell lines. In addition, compounds 6f and 10d induced arrest in the G2/M phase of the cell cycle as compared to untreated cells. Finally, in silico studies, including docking and molecular dynamic simulations, were performed to justify the biological results.

New proapoptotic chemotherapeutic agents based on the quinolone-3-carboxamide scaffold acting by VEGFR-2 inhibition.

In the current study, we designed and synthesized a series of new quinoline derivatives 10a-p as antiproliferative agents targeting cancer through inhibition of VEGFR-2. Preliminary molecular docking to assess the interactions of the designed derivatives with the binding site of VEGFR-2 (PDB code: 4ASD) displayed binding poses and interactions comparable to sorafenib. The synthesized compounds exhibited VEGFR-2 inhibitory activity with IC50 ranging from 36 nM to 2.23 µM compared to sorafenib (IC50 = 45 nM), where derivative 10i was the most potent. Additionally, the synthesized derivatives were evaluated in vitro for their cytotoxic activity against HepG2 cancer cell line. Seven compounds 10a, 10c, 10d, 10e, 10i, 10n and 10o (IC50 = 4.60, 4.14, 1.07, 0.88, 1.60, 2.88 and 2.76 µM respectively) displayed better antiproliferative activity than sorafenib (IC50 = 8.38 µM). Compound 10i was tested against Transformed Human Liver Epithelial-2 normal cell line (THLE-2) to evaluate its selective cytotoxicity. Furthermore, 10i, as a potent representative of the series, was assayed for its apoptotic activity and cell cycle kinetics' influence on HepG2, its effects on the gene expression of VEGFR-2, and protein expression of the apoptotic markers Caspase-7 and Bax. Compound 10i proved to have a potential role in apoptosis by causing significant increase in the early and late apoptotic quartiles, a remarkable activity in elevating the relative protein expression of Bax and Caspase-7 and a significant reduction of VEGFR-2 gene expression. Collectively, the obtained results indicate that compound 10i has a promising potential as a lead compound for the development of new anticancer agents.

Fragment merging approach for the design of thiazole/thiazolidine clubbed pyrazoline derivatives as anti-inflammatory agents: Synthesis, biopharmacological evaluation and molecular modeling studies.

Fragment merging approach was applied for the design of thiazole/thiazolidinone clubbed pyrazoline derivatives 5a-e, 6a-c, 7 and 10a-d as dual COX-2 and 5-LOX inhibitors. Compounds 5a, 6a, and 6b were the most potent and COX-2 selective inhibitors (IC50= 0.03-0.06 µM, SI = 282.7-472.9) with high activity against 5-LOX (IC50 = 4.36-4.86 µM), while compounds 5b and 10a were active and selective 5-LOX inhibitors with IC50 = 2.43 and 1.58 µM, respectively. In vivo assay and histopathological examination for most active candidate 6a revealed significant decrease in inflammation with higher safety profile in comparison to standard drugs. Compound 6a exhibited the same orientation and binding interactions as the reference COX-2 and 5-LOX inhibitors (celecoxib and quercetin, respectively). Consequently, compound 6a has been identified as a potential lead for further optimization and the development of safe and effective anti-inflammatory drugs.

Development of novel anilinoquinazoline-based carboxylic acids as non-classical carbonic anhydrase IX and XII inhibitors.

As part of our ongoing endeavour to identify novel inhibitors of cancer-associated CA isoforms IX and XII as possible anticancer candidates, here we describe the design and synthesis of small library of 2-aryl-quinazolin-4-yl aminobenzoic acid derivatives (6a-c, 7a-c, and 8a-c) as new non-classical CA inhibitors. On account of its significance in the anticancer drug discovery and in the development of effective CAIs, the 4-anilinoquinazoline privileged scaffold was exploited in this study. Thereafter, the free carboxylic acid functionality was appended in the ortho (6a-c), meta (7a-c), or para-positon (8a-c) of the anilino motif to furnish the target inhibitors. All compounds were assessed for their inhibitory activities against the hCA I, II (cytosolic), IX, and XII (trans-membrane, tumour-associated) isoforms. Moreover, six quinazolines (6a-c, 7b, and 8a-b) were chosen by the NCI-USA for in vitro anti-proliferative activity evaluation against 59 human cancer cell lines representing nine tumour subpanels.

Design and synthesis of novel cytotoxic fluoroquinolone analogs through topoisomerase inhibition, cell cycle arrest, and apoptosis.

To exploit the advantageous properties of approved drugs to hasten anticancer drug discovery, we designed and synthesized a series of fluoroquinolone (FQ) analogs via functionalization of the acid hydrazides of moxifloxacin, ofloxacin, and ciprofloxacin. Under the NCI-60 Human Tumor Cell Line Screening Assay, (IIIf) was the most potent among moxifloxacin derivatives, whereas (VIb) was the only ofloxacin derivative with significant effects and ciprofloxacin derivatives were devoid of activity. (IIIf) and (VIb) were further selected for five-dose evaluation, where they showed potent growth inhibition with a mean GI50 of 1.78 and 1.45 µM, respectively. (VIb) elicited a more potent effect reaching sub-micromolar level on many cell lines, including MDA-MB-468 and MCF-7 breast cancer cell lines (GI50 = 0.41 and 0.42 µM, respectively), NSCLC cell line HOP-92 (GI50 = 0.50 µM) and CNS cell lines SNB-19 and U-251 (GI50 = 0.51 and 0.61 µM, respectively). (IIIf) and (VIb) arrested MCF-7 cells at G1/S and G1, respectively, and induced apoptosis mainly through the intrinsic pathway as shown by the increased ratio of Bax/Bcl-2 and caspase-9 with a lesser activation of the extrinsic pathway through caspase-8. Both compounds inhibited topoisomerase (Topo) with preferential activity on type II over type I and (VIb) was marginally more potent than (IIIf). Docking study suggests that (IIIf) and (VIb) bind differently to Topo II compared to etoposide. (IIIf) and (VIb) possess high potential for oral absorption, low CNS permeability and low binding to plasma proteins as suggested by in silico ADME calculations. Collectively, (IIIf) and (VIb) represent excellent lead molecules for the development of cytotoxic agents from quinolone scaffolds.

New 5-Aryl-1,3,4-Thiadiazole-Based Anticancer Agents: Design, Synthesis, In Vitro Biological Evaluation and In Vivo Radioactive Tracing Studies.

A new series of 5-(4-chlorophenyl)-1,3,4-thiadiazole-based compounds featuring pyridinium (3), substituted piperazines (4a-g), benzyl piperidine (4i), and aryl aminothiazoles (5a-e) heterocycles were synthesized. Evaluation of the cytotoxicity potential of the new compounds against MCF-7 and HepG2 cancer cell lines indicated that compounds 4e and 4i displayed the highest activity toward the tested cancer cells. A selectivity study demonstrated the high selective cytotoxicity of 4e and 4i towards cancerous cells over normal mammalian Vero cells. Cell cycle analysis revealed that treatment with either compound 4e or 4i induced cell cycle arrest at the S and G2/M phases in HepG2 and MCF-7 cells, respectively. Moreover, the significant increase in the Bax/Bcl-2 ratio and caspase 9 levels in HepG2 and MCF-7 cells treated with either 4e or 4i indicated that their cytotoxic effect is attributed to the ability to induce apoptotic cell death. Finally, an in vivo radioactive tracing study of compound 4i proved its targeting ability to sarcoma cells in a tumor-bearing mice model.

Identification of novel piperazine-tethered phthalazines as selective CDK1 inhibitors endowed with in vitro anticancer activity toward the pancreatic cancer.

Pharmacologic inhibition of the oncogenic protein kinases using small molecules is a promising strategy to combat several human malignancies. CDK1 is an example of such a valuable target for the management of pancreatic ductal adenocarcinomas (PDAC); its overexpression in PDAC positively correlates with the size, histological grade and tumor aggressiveness. Here we report the identification of novel series of 1-piperazinyl-4-benzylphthalazine derivatives (8a-g, 10a-i and 12a-d) as promising anticancer agents with CDK1 inhibitory activity. The anti-proliferative activity of these agents was first screened on a panel of 11 cell lines representing 5 cancers (pancreas, melanoma, leukemia, colon and breast), and then confirmed on two CDK1-overexpressing PDAC cell lines (MDA-PATC53 and PL45 cells). Phthalazines 8g, 10d and 10h displayed potent activity against MDA-PATC53 (IC50 = 0.51, 0.88 and 0.73 µM, respectively) and PL45 (IC50 = 0.74, 1.14 and 1.00 µM, respectively) cell lines. Furthermore, compounds 8g, 10d and 10h exhibited potent and selective inhibitory activity toward CDK1 with IC50 spanning in the range 36.80-44.52 nM, whereas they exerted weak inhibitory effect on CDK2, CDK5, AXL, PTK2B, FGFR, JAK1, IGF1R and BRAF kinases. Western blotting of CDK1 in MDA-PATC53 cells confirmed the ability of target phthalazines to diminish the CDK1 levels, and cell cycle analyses revealed their ability to arrest the cell cycle at G2/M phase. In conclusion, a panel of potent and selective CDK1 inhibitors were identified which can serve as lead compounds for designing further CDK1 inhibitors.

Multi-Step In Silico Discovery of Natural Drugs against COVID-19 Targeting Main Protease.

In continuation of our antecedent work against COVID-19, three natural compounds, namely, Luteoside C (130), Kahalalide E (184), and Streptovaricin B (278) were determined as the most promising SARS-CoV-2 main protease (Mpro) inhibitors among 310 naturally originated antiviral compounds. This was performed via a multi-step in silico method. At first, a molecular structure similarity study was done with PRD_002214, the co-crystallized ligand of Mpro (PDB ID: 6LU7), and favored thirty compounds. Subsequently, the fingerprint study performed with respect to PRD_002214 resulted in the election of sixteen compounds (7, 128, 130, 156, 157, 158, 180, 184, 203, 204, 210, 237, 264, 276, 277, and 278). Then, results of molecular docking versus Mpro PDB ID: 6LU7 favored eight compounds (128, 130, 156, 180, 184, 203, 204, and 278) based on their binding affinities. Then, in silico toxicity studies were performed for the promising compounds and revealed that all of them have good toxicity profiles. Finally, molecular dynamic (MD) simulation experiments were carried out for compounds 130, 184, and 278, which exhibited the best binding modes against Mpro. MD tests revealed that luteoside C (130) has the greatest potential to inhibit SARS-CoV-2 main protease.

Insights into the effect of elaborating coumarin-based aryl enaminones with sulfonamide or carboxylic acid functionality on carbonic anhydrase inhibitory potency and selectivity.

Recently, different mechanisms for inhibition of carbonic anhydrases (CAs) have been reported, such as the classical zinc-binding (exerted by sulfonamides and carboxylic acids) as well as occluding the entrance of the CA active site (exerted by coumarins). In this manuscript, we studied the effect of combining the pharmacopheric parts responsible for these two mechanisms on CA inhibitory potency and selectivity through the design and synthesis of novel coumarins tethered with the zinc-binding sulfonamide (5a-f, 11a-b and 13a-b) or carboxylic acid (7a-f) groups. In addition, another set of coumarin derivatives (9a-b) with no zinc-binding group (ZBG) was designed to act as non-classical CA inhibitors. The synthesized coumarins were examined for their inhibitory activities towards four hCA isoforms I, II, IX and XII. Coumarin sulfonamides (5a-f, 11a-b and 13a-b) effectively inhibited both tumor-associated hCA IX (KIs: 8.9-133.5 nM) and hCA XII (KIs: 3.4-42.9 nM) isoforms, whereas coumarin carboxylic acids (7a-f) weakly affected hCA IX (KIs: 0.49-11.2 µM) and hCA XII (KIs: 0.51-10.1 µM) isoforms. The coumarin based inhibitors featuring zinc-binding sulfonamide or carboxylic acid group achieved low to moderate hCA IX/XII selectivity. Interestingly, the ZBG-free coumarin derivatives (9a-b) emerged not only as effective hCA IX (KIs = 93.3 and 63.8 nM, respectively) and hCA XII (KIs = 85.7 and 72.1 nM, respectively) inhibitors, but also as a highly hCA IX/XII selective inhibitors over the off-target hCA I/II isoforms (SIs > 1000). Coumarin 9a was further evaluated for its anti-proliferative effect on MCF-7 and PANC-1 cancer cell lines, as well as its effect on the cell cycle and apoptosis towards MCF-7 cell line.

Comparative Study of the Synthetic Approaches and Biological Activities of the Bioisosteres of 1,3,4-Oxadiazoles and 1,3,4-Thiadiazoles over the Past Decade.

The bioisosteres of 1,3,4-oxadiazoles and 1,3,4-thiadiazoles are well-known pharmacophores for many medicinally important drugs. Throughout the past 10 years, 1,3,4-oxa-/thiadiazole nuclei have been very attractive to researchers for drug design, synthesis, and the study of their potential activity towards a variety of diseases, including microbial and viral infections, cancer, diabetes, pain, and inflammation. This work is an up-to-date comparative study that identifies the differences between 1,3,4-thiadiazoles and 1,3,4-oxadiazoles concerning their methods of synthesis from different classes of starting compounds under various reaction conditions, as well as their biological activities and structure-activity relationship.

Dual PI3K/Akt Inhibitors Bearing Coumarin-Thiazolidine Pharmacophores as Potential Apoptosis Inducers in MCF-7 Cells.

Breast cancer is the most common malignancy worldwide; therefore, the development of new anticancer agents is essential for improved tumor control. By adopting the pharmacophore hybridization approach, two series of 7-hydroxyl-4-methylcoumarin hybridized with thiosemicarbazone (V-VI) and thiazolidin-4-one moieties (VII-VIII) were prepared. The in vitro anticancer activity was assessed against MCF-7 cells adopting the MTT assay. Nine compounds showed significant cytotoxicity. The most promising compound, VIIb, induced remarkable cytotoxicity (IC50 of 1.03 + 0.05 µM). Further investigations were conducted to explore its pro-apoptotic activity demonstrating S-phase cell cycle arrest. Apoptosis rates following VIIb treatment revealed a 5-fold and 100-fold increase in early and late apoptotic cells, correspondingly. Moreover, our results showed caspase-9 dependent apoptosis induction as manifested by an 8-fold increase in caspase-9 level following VIIb treatment. Mechanistically, VIIb was found to target the PI3K-α/Akt-1 axis, as evidenced by enzyme inhibition assay results reporting significant inhibition of examined enzymes. These findings were confirmed by Western blot results indicating the ability of VIIb to repress levels of Cyclin D1, p-PI3K, and p-Akt. Furthermore, docking studies showed that VIIb has a binding affinity with the PI3K binding site higher than the original ligands X6K. Our results suggest that VIIb has pharmacological potential as a promising anti-cancer compound by the inhibition of the PI3K/Akt axis.

Multi-stage structure-based virtual screening approach towards identification of potential SARS-CoV-2 NSP13 helicase inhibitors.

On account of its crucial role in the virus life cycle, SARS-COV-2 NSP13 helicase enzyme was exploited as a promising target to identify a novel potential inhibitor using multi-stage structure-based drug discovery approaches. Firstly, a 3D pharmacophore was generated based on the collected data from a protein-ligand interaction fingerprint (PLIF) study using key interactions between co-crystallised fragments and the NSP13 helicase active site. The ZINC database was screened through the generated 3D-pharmacophore retrieving 13 potential hits. All the retrieved hits exceeded the benchmark score of the co-crystallised fragments at the molecular docking step and the best five-hit compounds were selected for further analysis. Finally, a combination between molecular dynamics simulations and MM-PBSA based binding free energy calculations was conducted on the best hit (compound FWM-1) bound to NSP13 helicase enzyme, which identified FWM-1 as a potential potent NSP13 helicase inhibitor with binding free energy equals -328.6 ± 9.2 kcal/mol.

Synthesis, in vitro anticancer activity and in silico studies of certain isoxazole-based carboxamides, ureates, and hydrazones as potential inhibitors of VEGFR2.

The ensuing research presents the results of in vitro anticancer activity of novel 28 compounds of isoxazole-based carboxamides 3(a-d); ureates 4(a-g), 5, 6, 7a,b, 8; and hydrazones 9(a-f), 10(a-d), 11a,b as potential inhibitors of VEGFR2. The carboxamides and ureates were synthesized by converting 5-(aryl)-isoxzaole-3-carbohydrazides 1a,b to the corresponding carbonylazides 2a,b followed by treatment with the appropriate amines. The hydrazones were directly obtained through condensation of the carbohydrazide 1a,b with aldehydes and/or ketones. The structures of the target compounds were confirmed by elemental and spectral analyses. A preliminary in vitro anticancer screening of solutions (10-5M) on 60 cancer cell lines (NCI, USA) revealed that the carboxamide 3c is the most promising growth inhibitor. Explicitly, 3c showed potent anticancer activity at 10µ M against leukemia (HL-60(TB), K-562 and MOLT-4), colon cancer (KM12) and melanoma (LOX IMVI) cell lines with %GI range = 70.79-92.21. Evaluation of growth inhibitory activity of the synthesized compounds against hepatocellular carcinoma (HepG2), that overexpresses VEGFR2, showed superior activity of compounds 8, 10a and 10c with IC50 in sub micromolar concentrations of 0.84, 0.79 and 0.69 µM, respectively, which is better than that of the reference drug, Sorafenib (IC50 = 3.99 µM). Moreover, these compounds displayed high selective cytotoxicity for HepG2 cancer cells over the nontumorigenic THLE2 liver cells (SI range = 26.37-38.60) which reflect their safety. The results of VEGFR2 kinase inhibition assay demonstrate that, compounds 8 and 10a are the most active inhibitors with IC50 = 25.7 and 28.2 nM, respectively, (Sorafenib IC50 = 28.1 nM). Molecular docking of the synthesized derivatives to VEGFR2 (PDB: 3WZE) showed similar binding modes to that of the co-crystallized ligand, sorafenib. Moreover, the results of computational assessment of ADME and drug-likeness characteristics inspire further investigations of the new isoxazole-based derivatives to afford more potent, safe and orally active VEGFR2 inhibitors as potential anticancer drug candidates.

Development of novel isatin-nicotinohydrazide hybrids with potent activity against susceptible/resistant Mycobacterium tuberculosis and bronchitis causing-bacteria.

Joining the global fight against Tuberculosis, the world's most deadly infectious disease, herein we present the design and synthesis of novel isatin-nicotinohydrazide hybrids (5a-m and 9a-c) as promising anti-tubercular and antibacterial agents. The anti-tubercular activity of the target hybrids was evaluated against drug-susceptible M. tuberculosis strain (ATCC 27294) where hybrids 5d, 5g and 5h were found to be as potent as INH with MIC = 0.24 µg/mL, also the activity was evaluated against Isoniazid/Streptomycin resistant M. tuberculosis (ATCC 35823) where compounds 5g and 5h showed excellent activity (MIC = 3.9 µg/mL). Moreover, the target hybrids were examined against six bronchitis causing-bacteria. Most derivatives exhibited excellent antibacterial activity. K. pneumonia emerged as the most sensitive strain with MIC range: 0.49-7.81 µg/mL. Furthermore, a molecular docking study has proposed DprE1 as a probable enzymatic target for herein reported isatin-nicotinohydrazide hybrids, and explored the binding interactions within the vicinity of DprE1 active site.

Design and synthesis of pyrimidine-5-carbonitrile hybrids as COX-2 inhibitors: Anti-inflammatory activity, ulcerogenic liability, histopathological and docking studies.

Two new series of 1,3,4-oxadiazole and coumarin derivatives based on pyrimidine-5-carbonitrile scaffold have been synthesized and evaluated for their COX-1/COX-2 inhibitory activity. Compounds 10c, 10e, 10h-j, 14e-f, 14i and 16 were found to be the most potent and selective inhibitors of COX-2 (IC50 0.041-0.081 µM, SI 139.74-321.95). Eight compounds were further investigated for their in vivo anti-inflammatory activity. The most active derivatives 10c, 10j and 14e displayed superior in vivo anti-inflammatory activity (% edema inhibition 39.3-48.3, 1 h; 58.4-60.5, 2 h; 70.8-83.2, 3 h; 78.9-89.5, 4 h) to the reference drug celecoxib (% edema inhibition 38.0, 1 h; 48.8, 2 h; 58.4, 3 h; 65.4, 4 h). These derivatives were also tested for their ulcerogenic liability, compound 10j showed better safety profile with reference to celecoxib while 10c and 14e exhibited mild lesions. Molecular docking studies of 10c, 10j, and 14e in the COX-2 active site revealed similar orientation and binding interactions as selective COX-2 inhibitors with a higher liability to access the selectivity side pocket.

Novel 3-substituted coumarins as selective human carbonic anhydrase IX and XII inhibitors: Synthesis, biological and molecular dynamics analysis.

In this study, diverse series of coumarin derivatives were developed as potential carbonic anhydrase inhibitors (CAIs). A "tail" approach was adopted by selecting the coumarin motif as a tail that is connected to the ZBG benzenesulfonamide moiety via a hydrazine (4a,b) or hydrazide (5a,b) linker. Thereafter, an aryl sulfone tail was incorporated to afford the dual tailed coumarin-sulfonamide arylsulfonehydrazones (13a-d) and hydrazides (14a,b). Then, the ZBG were removed from compounds 13 and 14 to furnish coumarin arylsulfonehydrazones (11a-d) and hydrazides (12a,b). Coumarin-sulfonamides 4 and 5 emerged as non-selective CAIs as they displayed good inhibitory activities toward all the examined CA isozymes (I, II, IX and XII) in the nanomolar ranges. Interestingly, the "dual-tail" approach (compounds 13 and 14) succeeded in achieving a good activity and selectivity toward CA IX/XII over the physiologically dominant CA I/II. In particular, compounds 13d and 14a were the most selective coumarin-sulfonamide counterparts. Concerning non-sulfonamide coumarin derivatives, coumarins 8 exhibited excellent activity and selectivity profiles against the target hCA IX/XII, whereas, coumarins 11 and 12 reported excellent selectivity profile, but they barely inhibited hCA IX/XII with KIs spanning in the micromolar ranges. Furthermore, molecular modelling studies were applied to get a deep focus about the feasible affinities and binding interactions for target coumarin-sulfonamides 4, 5, 13 and 14 with the active site for CA II, IX and XII isoforms.

Synthesis and biological evaluation of novel pyrimidine-5-carbonitriles featuring morpholine moiety as antitumor agents.

Aim: Design and synthesis of novel morpholinopyrimidine-5-carbonitriles as antitumor agents. Materials & methods: New series of morpholinopyrimidine-5-carbonitriles have been synthesized. 19 derivatives (3b, 4a, 5-6, 9-12, 13a-e, 14a-c and 15-17) were evaluated for their in vitro antitumor activity by the National Cancer Institute (NCI; MD, USA). Moreover, compound 13e was evaluated against PI3K (α, ß and δ) and the mechanism of its cytotoxic activity on leukemia SR was studied. Results: Compound 13e possessed remarkable broad spectrum antitumor activity with GI50 (median growth inhibition) and TGI (total growth inhibition) values of 6.15 and 28.66 µM, respectively, caused cell cycle arrest at G2-M phase and significant increase in the percentage of annexin V-FITC - positive apoptotic cells, also increased the level of active caspase-3. Moreover, 13e revealed good safety profile against transformed human liver epithelial-2 (THLE2).