Theophylline-based hybrids as acetylcholinesterase inhibitors endowed with anti-inflammatory activity: synthesis, bioevaluation, in silico and preliminary kinetic studies.

In this study, we investigated the conjugation of theophylline with different compounds of natural origin hoping to construct new hybrids with dual activity against cholinergic and inflammatory pathways as potential agents for the treatment of Alzheimer's disease (AD). Out of 28 tested hybrids, two hybrids, acefylline-eugenol 6d and acefylline-isatin 19, were able to inhibit acetylcholinesterase (AChE) at low micromolar concentration displaying IC50 values of 1.8 and 3.3 µM, respectively, when compared to the galantamine standard AChE inhibitor. Moreover, the prepared hybrids exhibited a significant anti-inflammatory effect against lipopolysaccharide induced inflammation in RAW 264.7 and reduced nitric oxide (NO), tumor necrosis alpha (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) levels in a dose dependent manner. These hybrids demonstrated significant reductions in nitric oxide (NO), tumor necrosis alpha (TNF-α), interleukin-1ß (IL-1ß), and interleukin-6 (IL-6) levels in RAW 264.7 cells induced by lipopolysaccharide (LPS). The findings of this study were further explained in light of network pharmacology analysis which suggested that AChE and nitric oxide synthase were the main targets of the most active compounds. Molecular docking studies revealed their ability to bind to the heme binding site of nitric oxide synthase 3 (NOS-3) and effectively occupy the active site of AChE, interacting with both the peripheral aromatic subsite and catalytic triad. Finally, the compounds demonstrated stability in simulated gastric and intestinal environments, suggesting potential absorption into the bloodstream without significant hydrolysis. These findings highlight the possible therapeutic potential of acefylline-eugenol 6d and acefylline-isatin 19 hybrids in targeting multiple pathological mechanisms involved in AD, offering promising avenues for further development as potential treatments for this devastating disease.

Evaluation of antimicrobial, antiquorum sensing, and cytotoxic activities of new vanillin 1,2,3-triazole derivatives.

Vanillin (1), the main constituent of vanilla species, was used as a starting natural scaffold for the synthesis of five new (2-6) and one known (7) triazole derivatives via click chemistry using the copper (I)-catalyzed azide-alkyne cycloaddition method. Vanillin and its new derivatives; 4-{1-[2-Hydroxymethyl-5-(5 methyl-2,4-dioxo-3,4-dihydro-2H-pyrimidin-1-yl)-tetrahydro-furan-3-yl]-1H[1,2,3]triazol-4-ylmethoxy}-3-methoxy-benzaldehyde (2); [4-(4-Formyl-2methoxy-phenoxymethyl)-[1,2,3]triazol-1-yl]-acetic acid methyl ester (3); 4-[1-(4-Acetyl-phenyl)-1H-[1,2,3]triazol-4-ylmethoxy]-3-methoxy-benzaldehyde (4); 4-[4-(1-Benzyl-1H-[1,2,3]triazol-4-ylmethoxy)-3-methoxy-phenyl]-but-3-en-2-one (5); and 4-[4-(1-Benzyl-1H-[1,2,3]triazol-4-ylmethoxy)-3-methoxy-phenyl]-4-hydroxy-butan-2-one (6), as well as the previously known derivative (7) were subjected to antimicrobial, antiquorum-sensing and cytotoxic evaluation. Compounds 4-7 possessed the most notable enhancement in the anti-bacterial activity against Bacillus cereus, Pseudomonas aeruginosa and antifungal activity against Candida albicans. However, compounds 1 and 2 exhibited high antiquorum-sensing activity against Chromobacterium violaceum using catechin as a positive control. Compounds 4-7 demonstrated selective cytotoxicity against MCF-7 and HepG2 cancer cells compared to normal lung fibroblast cells (WI-38). These findings proved the usefulness of synthesis bioactive derivatives from vanillin through chemical modifications.

Down regulation of fatty acid synthase via inhibition of PI3K/AKT/mTOR in ovarian cancer cell line by novel organoselenium pseudopeptide.

Ovarian cancer (OC) is the 7th most common cancer in women world-wide and the 3rd most common female cancer. For the treatment of OC, there is no successful therapeutic. The medications that are currently available have significant side effects and a low therapeutic index. This work aimed to evaluate the anticancer activity of organoselenium pseudopeptide compound against OC cell lines. After treatment with 50 â€‹µM of compound 4 (CPD 4), the viability was determined. The anticancer activity was further investigated by different methods including cell cycle and apoptosis analysis, colony formation assay, zymography, comet assay and Western blot. In comparison to a positive control, compound 4 showed cytotoxicity toward A2780CP cells rather than A2780 and SKOV-3 â€‹cells. Compound 4 was more selective to OC cells rather than HSF cells. Moreover, Compound 4 was able to inhibit cell migration and proliferation. The anticancer effect of compound 4 was found to be partially via cell cycle arrest, overexpression of p27 â€‹cell cycle inhibitor and induction of apoptosis through DNA fragmentation and activated production of ROS. Compound 4 had a differential effect on the modulation of PI3K/AKT/mTOR signaling pathway in the OC treated cell lines, also inhibited lipogenesis process via downregulation of FASN expression. Conclusion: This work highlights the unique role of Compound 4 against OC via modulation of oxidative stress, inhibition of survival PI3K/AKT/mTOR pathway. Compound 4 was found to be a promising alternative therapy for the treatment of OC in this investigation.

Novel spirooxindole based benzimidazole scaffold: In vitro, nanoformulation and in vivo studies on anticancer and antimetastatic activity of breast adenocarcinoma.

The present work provided in vitro anticancer investigation of novel spirooxindole based benzimidazole scaffold SP1 and its nanoformulation with in vivo evaluation of anticancer and antimetastatic activity as potential drug for breast adenocarcinoma. The synthesized compound SP1 exhibited potent growth inhibitory efficacy against four types of human cancer (breast, prostate, colon and lung) cell lines with IC50 = 2.4, 3.4, 7.24 and 7.81 µM and selectivity index 5.79, 4.08, 1.93 and 1.78 respectively. Flow cytometric analysis illustrated that SP1 exhibited high apoptotic effect on all tested cancer cell lines (38.22-52.3 %). The mode of action of this promising compound was declared by its ability to upregulate the gene expression of p21 (2.29-3.91 folds) with suppressing cyclin D (1.9-8.93 folds) and NF-κB (1.26-1.44 fold) in the treated cancer cells. Also, it enhanced the protein expression of apoptotic marker p53 and moderate binding affinity for MDM2 (KD;7.94 µM). Notwithstanding these promising impressive findings, its selectivity against cancer cell lines and safety on normal cells were improved by nanoformulation. Therefore, SP1 was formulated as ultra-flexible niosomal nanovesicles (transethoniosomes). The ultra-deformability is attributable to the synergism between ethanol and edge activators in improving the flexibility of the nanovesicular membrane. F8 exhibited high deformability index (DI) of (23.48 ± 1.4). It was found that % SP1 released from the optimized transethoniosomal formula (F8) after 12 h (Q12h) was 84.17 ± 1.29 % and its entrapment efficiency (%EE) was 76.48 ± 1.44 %. Based upon the very encouraging and promising in vitro results, an in vivo study was carried out in female Balb/c mice weighing (15-25 g). SP1 did halt the proliferation of breast cancer cells as well as suppressed the metastasis in other organs like liver, lung and heart.

Natural inspired piperine-based ureas and amides as novel antitumor agents towards breast cancer.

In this work, the natural piperine moiety was utilised to develop two sets of piperine-based amides (5a-i) and ureas (8a-y) as potential anticancer agents. The anticancer action was assessed against triple negative breast cancer (TNBC) MDA-MB-231, ovarian A2780CP and hepatocellular HepG2 cancer cell lines. In particular, 8q stood out as the most potent anti-proliferative analogue against TNBC MDA-MB-231 cells with IC50 equals 18.7 µM, which is better than that of piperine (IC50 = 47.8 µM) and 5-FU (IC50 = 38.5 µM). Furthermore, 8q was investigated for its possible mechanism of action in MDA-MB-231 cells via Annexin V-FITC apoptosis assay and cell cycle analysis. Moreover, an in-silico analysis has proposed VEGFR-2 as a probable enzymatic target for piperine-based derivatives, and then has explored the binding interactions within VEGFR-2 active site (PDB:4ASD). Finally, an in vitro VEGFR-2 inhibition assay was performed to validate the in silico findings, where 8q showed good VEGFR-2 inhibitory activity with IC50 = 231 nM.

Natural inspired piperine-based sulfonamides and carboxylic acids as carbonic anhydrase inhibitors: Design, synthesis and biological evaluation.

The natural product piperine, the major bioactive alkaloid present in black pepper fruits, has the ability to modulate the functional activity of several biological targets. In this study, we have utilized the natural piperine as a tail moiety to develop new SLC-0111 analogues (6a-d, 8 and 9) as potential carbonic anhydrase inhibitors. Thereafter, different functionalities, free carboxylic acid (11a-c), acetyl (13a) and ethyl ester (13b-c), were exploited as bioisosteres of the sulfamoyl functionality. All piperine-based derivatives were assessed for their inhibitory actions against four human (h) CA isoforms: hCA I, II, IX and XII. The best hCA inhibitory activity was observed for the synthesized primary piperine-sulfonamides (6a-d and 8). In particular, both para-regioisomers (6c and 8) emerged as the most potent hCA inhibitors in this study with two-digit nanomolar activity against hCA II (KIs = 93.4 and 88.6 nM, respectively), hCA IX (KIs = 38.7 and 68.2 nM, respectively), and hCA XII (KIs = 57.5 and 45.6 nM, respectively). Moreover, piperine-sulfonamide 6c was examined for its anti-cancer and pro-apoptotic actions towards breast MCF-7 cancer cell line. Collectively, piperine-based sulfonamides could be considered as a promising scaffold for development of efficient anticancer candidates with potent CA inhibitory activities.

Sterols and Triterpenes from Dobera glabra Growing in Saudi Arabia and Their Cytotoxic Activity.

A new lupane caffeoyl ester, lup-20(29)-ene 3ß-caffeate-30-al (7), and a new oleanane-type triterpene, 3ß-hydroxyolean-13(18)-en-12-one (17), were isolated from the aerial parts of Dobera glabra (Forssk), along with ten known triterpenes, including seven lupane-type lupeol (1), 30-nor-lup-3ß-ol-20-one (2), ∆1-lupenone (3), lup-20(29)-en-3ß,30-diol (4), lupeol caffeate (5), 30-hydroxy lup-20(29)-ene 3ß-caffeate (6), and betunaldehyde (8); three oleanane-type compounds were also identified, comprising δ-amyrone (15), δ-amyrin (16), and 11-oxo-ß-amyrin (18); together with six sterols, comprising ß-sitosterol (9), stigmasterol (10), 7α-hydroxy-ß-sitosterol (11), 7α-hydroxy-stigmasterol (12), 7-keto-ß-sitosterol (13), and 7-keto-stigmasterol (14). Their structures were elucidated using a variety of spectroscopic techniques, including 1D (1H, 13C, and DEPT-135 13C) and 2D (1H-1H COSY, 1H-13C HSQC, and 1H-13C HMBC) nuclear magnetic resonance (NMR) and accurate mass spectroscopy. Subsequently, the different plant extracts and some of the isolated compounds (1-9, 11 and 13) were investigated for their possible cytotoxic activity in comparison to cisplatin against a wide array of aggressive cancer cell lines, such as colorectal cancer (HCT-116), hepatocellular carcinoma (HepG-2), and prostate cancer (PC-3) cell lines. Compound 11 displayed broad cytotoxicity against all of the tested cell lines (IC50 ≅ 8 µg/mL in all cases), and a high safety margin against normal Vero cells (IC50 = 70 µg/mL), suggesting that 11 may be a highly selective and effective anticancer agent candidate. Notably, the evidence indicated that the mode of action of compound 11 could possibly consist of the inhibition of phosphodiesterase I (80.2% enzyme inhibition observed at 2 µM compound concentration).

Anticancer activity of new cationic arylthiophenes against hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) is the second most common cancer-related death in the world. No effective curative option exists for the treatment of HCC. The available drugs exhibit severe toxic effects and low therapeutic index. AIM: This work aimed to examine different monocationic arylthiophene derivatives for possible use as chemotherapeutic agents against HCC. METHODS: The IC50 values for the compounds were determined. The mechanism of cytotoxicity was further investigated using different methods. RESULTS: Compound 2j proved to retain the highest cytotoxicity in comparison to as a positive control. The selectivity index of compound 2j revealed the safety to normal cells. Moreover, compound 2j was able to inhibit HepG2 cells´ migration and division. The anticancer effect of compound 2j was found to be partially via cell cycle arrest, activation of the tumour suppressor p53 protein, and induction of apoptosis via both intrinsic and extrinsic pathways. Compound 2j has a potential sensitization activity and significantly reduced the IC50 values for the anticancer drugs doxorubicin, cisplatin, and taxol. CONCLUSION: The tested arylthiophenes showed a potent cytotoxicity against HepG2 cells and were safe to normal cells. The most active compound 2j was found to be able to inhibit cell division and migration and also to induce apoptosis. Compound 2j also proved to have a sensitization effect on standard anticancer drugs.

Synthesis of new selective cytotoxic ricinine analogues against oral squamous cell carcinoma.

Sixteen new analogues were synthesized from ricinine and tested alongside with seven known analogues for their cytotoxic activity against oral cancer (SAS cells) and normal epithelial cells (L132 cells). In contrast to 5-FU, the synthesized ricinine analogues did not show toxicity to normal cells. However, some of them inhibited the proliferation of oral cancer cells at 25 µM as evident from the MTT assay results. Ricinine analogue (19) was shown to be the most active derivative (69.22% inhibition). Potential targets involved in the oral cancer inhibitory activity of compound 19 were investigated using in-silico studies and western blot analysis. PTP1B was predicted to be a target for ricinine using reverse docking approach. This prediction was confirmed by western blot analysis that revealed the downregulation of PTP1B protein by compound 19. Moreover, it showed downregulation of COX-2 which is also extensively expressed in oral cancer.

Repurposing of quinoline alkaloids identifies their ability to enhance doxorubicin-induced sub-G0/G1 phase cell cycle arrest and apoptosis in cervical and hepatocellular carcinoma cells.

The ability of quinoline alkaloids (cinchonine, cinchonidine, quinine, and quinidine) to sensitize different human cancer cell lines to doxorubicin (DOX)-induced cell death was evaluated. Cell viability was analyzed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the alkaloids ability to enhance DOX-induced apoptosis was explored using Western blotting analysis. Also, flow cytometry was applied to analyze cell fractions in the different cell cycle phases. All alkaloids showed a significant enhancement of DOX-induced cell death in HeLa and HepG2 cell lines. The chemosensitizing activity of the quinoline alkaloids was attributed to the induction of apoptosis as indicated by splitting of caspase-3 and its substrate poly (ADP-ribose) polymerase (PARP). In addition, there was an increase in the cell fractions in sub-G0/G1 phase in case of DOX combination with the alkaloids. This study proves the ability of the quinoline alkaloids to enhance DOX-induced apoptotic cell death in human cervical and hepatocellular carcinoma cells.

Effect of phenolic compounds from the leaves of Psidium guajava on the activity of three metabolism-related enzymes.

Enzyme activity modulation by synthetic compounds provide strategies combining the inhibitory and therapeutic mode of action of the confirmed inhibitors. However, natural modulators could offer a valuable alternative for synthetic ones for the treatment of different chronic diseases (diabetes, hypertension, cancer); due to the numerous side effects of the latter. In vitro screening assays were conducted for Psidium guajava leaf methanolic extract against three metabolism-related enzymes; α-amylase, tyrosinase, and hyaluronidase. The obtained results showed that the examined extract retained weak and moderate multitarget inhibition against α-amylase, tyrosinase, and hyaluronidase, respectively; however, the leaf fractions exhibited stronger inhibitions for the three investigated enzymes. Fractionation of P. guajava leaf extract revealed that anthraquinones and ellagic acid are of the major active compounds with inhibitory activities for α-amylase, tyrosinase, and hyaluronidase. Kinetic studies showed that quinalizarin inhibition is competitive for both α-amylase and hyaluronidase, and ellagic acid inhibition for tyrosinase and hyaluronidase is competitive and un-competitive, respectively. The molecular docking studies of quinalizarin and ellagic acid with α-amylase, tyrosinase, and hyaluronidase showed high binding energies with different bonds stabilizing the ligand-protein complex. Compiling all obtained results led to conclude that both P. guajava leaf fractions, quinalizarin and ellagic acid, have multitarget activities with potential therapeutic applications in many metabolic disorders.

Correction: Curcumin attenuates iron accumulation and oxidative stress in the liver and spleen of chronic iron-overloaded rats.

[This corrects the article DOI: 10.1371/journal.pone.0134156.].

Development of Provesicular Nanodelivery System of Curcumin as a Safe and Effective Antiviral Agent: Statistical Optimization, In Vitro Characterization, and Antiviral Effectiveness.

Curcumin is a natural compound that has many medical applications. However, its low solubility and poor stability could impede its clinical applications. The present study aimed to formulate dry proniosomes to overcome these pitfalls and improve the therapeutic efficacy of Curcumin. Curcumin-loaded proniosomes were fabricated by the slurry method according to 32 factorial design using Design-Expert software to demonstrate the impact of different independent variables on entrapment efficiency (EE%) and % drug released after 12 h (Q12h). The optimized formula (F5) was selected according to the desirability criteria. F5 exhibited good flowability and appeared, after reconstitution, as spherical nanovesicles with EE% of 89.94 ± 2.31% and Q12h of 70.89 ± 1.62%. F5 demonstrated higher stability and a significant enhancement of Q12h than the corresponding niosomes. The docking study investigated the ability of Curcumin to bind effectively with the active site of DNA polymerase of Herpes simplex virus (HSV). The antiviral activity and the safety of F5 were significantly higher than Curcumin. F5 improved the safety of Acyclovir (ACV) and reduced its effective dose that produced a 100% reduction of viral plaques. Proniosomes could be promising stable carriers of Curcumin to be used as a safe and efficient antiviral agent.

Bioassay-Guided Isolation, Metabolic Profiling, and Docking Studies of Hyaluronidase Inhibitors from Ravenala madagascariensis.

Hyaluronidase enzyme (HAase) has a role in the dissolution or disintegration of hyaluronic acid (HA) and in maintaining the heathy state of skin. Bioassay-guided fractionation of Ravenala madagascariensis (Sonn.) organ extracts (leaf, flower, stem, and root) testing for hyaluronidase inhibition was performed followed by metabolic profiling using LC-HRMS. Additionally, a hyaluronidase docking study was achieved using Molecular Operating Environment (MOE). Results showed that the crude hydroalcoholic (70% EtOH) extract of the leaves as well as its n-butanol (n-BuOH) partition showed higher HAase activity with 64.3% inhibition. Metabolic analysis of R. madagascariensis resulted in the identification of 19 phenolic compounds ranging from different chemical classes (flavone glycosides, flavonol glycosides, and flavanol aglycones). Bioassay-guided purification of the leaf n-BuOH partition led to the isolation of seven compounds that were identified as narcissin, rutin, epiafzelechin, epicatechin, isorhamnetin 7-O-glucoside, kaempferol, and isorhamnetin-7-O-rutinoside. The docking study showed that narcissin, rutin, and quercetin 3-O-glucoside all interact with HAase through hydrogen bonding with the Asp111, Gln271, and/or Glu113 residues. Our results highlight Ravenala madagascariensis and its flavonoids as promising hyaluronidase inhibitors in natural cosmetology preparations for skin care.

Effect of phenolic compounds from the rind of Punica granatum on the activity of three metabolism-related enzymes.

Enzyme activity modulation by synthetic compounds provide strategies combining the inhibitory and therapeutic mode of action of the confirmed inhibitors. However, natural modulators could offer a valuable alternative for synthetic ones for the treatment of different chronic diseases (diabetes, hypertension, cancer) due to the numerous side effects of the latter. In vitro screening assays were conducted for Punica granatum rind methanolic extract against three metabolism-related enzymes: α-amylase, tyrosinase, and hyaluronidase. The obtained results showed that the examined extract retained high multitarget inhibition with inhibition percentages 31.5 ± 1.3%, 75.9 ± 4.7%, and 68.5 ± 5.3% against α-amylase, tyrosinase, and hyaluronidase, respectively. Bioguided fractionation of P. granatum rind extract revealed that quercetin is the major active compound with inhibitory activities: 54.3 ± 2.7%, 94.2 ± 3.5%, and 90.9 ± 2.7% against α-amylase, tyrosinase, and hyaluronidase, respectively. Kinetic studies of enzymes showed that quercetin inhibition was noncompetitive, uncompetitive, and competitive for α-amylase, tyrosinase, and hyaluronidase, respectively. The molecular docking of quercetin with α-amylase and hyaluronidase showed high binding energy with different bonds stabilizing the ligand-protein complex. Compiling all obtained results led to conclude that both P. granatum rind extract and quercetin have multitarget activities with potential therapeutic applications in many metabolic disorders.

Anticancer Indole-Based Chalcones: A Structural and Theoretical Analysis.

The crystal structures of five new chalcones derived from N-ethyl-3-acetylindole with different substituents were investigated: (E)-3-(4-bromophenyl)-1-(1-ethyl-1H-indol-3-yl)prop-2-en-1-one (3a); (E)-3-(3-bromophenyl)-1-(1-ethyl-1H-indol-3-yl)prop-2-en-1-one (3b); (E)-1-(1-ethyl-1H-indol-3-yl)-3-(4-methoxyphenyl)prop-2-en-1-one (3c); (E)-1-(1-ethyl-1H-indol-3-yl)-3-mesitylprop-2-en-1-one (3d); and (E)-1-(1-ethyl-1H-indol-3-yl)-3-(furan-2-yl)prop-2-en-1-one (3e). The molecular packing of the studied compounds is controlled mainly by C-H⋅⋅⋅O hydrogen bonds, C-H⋅⋅⋅π interactions, and π···π stacking interactions, which were quantitatively analyzed using Hirshfeld topology analysis. Using density functional theory (DFT) calculations, the order of polarity (3b ˂ 3d ˂ 3e ˂ 3a ˂ 3c) was determined. Several chemical reactivity indices such as the ionization potential (I), electron affinity (A), chemical potential (µ), hardness (η), electrophilicity (ω) and nucleophilicity (N) indices were calculated, and these properties are discussed and compared. In addition, the antiproliferative activity of the five new chalcones was studied.

An Approach to Treatment of Liver Cancer by Novel Glycyrrhizin Derivative.

BACKGROUND: Liver cancer is a life threating disease as it is the fifth most common cancer and the third most common cause of death worldwide with no safe, efficient, and economic drug available for treatment. METHODS: This study intended to investigate glycyrrhizin and its derivatives for possible use as a cytotoxic agent and as a drug for liver cancer treatment. Thus, after treatment of liver cancer cell line HepG-2 with 50 µM of each compound, cell viability was determined. RESULTS: The cytotoxicity assay showed glycyrrhizin derivatives ME-GA (18ß-Glycyrrhetinic-30-methyl ester) and AKBA (3-acetyl-11- keto-ß-Boswellic acid) to be the most potent drug against liver cancer cell line HepG-2 with IC50 values 25.50 ± 1.06 and 19.73 ± 0.89 µM, respectively. Both the compounds showed higher selectivity towards hepatocellular carcinoma rather than the normal lung fibroblast cell line WI-38. The presence of methyl ester at C-30 greatly increased the cytotoxicity of ME-GA which might be attributed to its higher activity and selectivity. Both ME-GA and AKBA contributed to inhibit cancer cell migration in the wound healing assay and impeded colony formation. The use of flow cytometry to carry out cell cycle analysis and the determination of possible mechanisms of action for apoptosis revealed that ME-GA arrested the cell cycle at G2/M that led to the inhibition of hepatocellular carcinoma and induced apoptosis via the extrinsic pathway and its ability to increase p53 transactivation. CONCLUSION: This work highlights the cytotoxicity of glycyrrhizin and its derivatives for possible use as a chemotherapeutic agent against hepatocellular carcinoma cells HepG-2. The most cytotoxic compound was ME-GA (18ß-Glycyrrhetinic-30-methyl ester) with no cytotoxic effect on the normal cell line. In summary, this new derivative may be used as an alternative or complementary medicine for liver cancer.

Targeting hepatocellular carcinoma: Synthesis of new pyrazole-based derivatives, biological evaluation, DNA binding, and molecular modeling studies.

A new series of pyrazole derivatives was prepared in this work, including pyrazolopyrimidines, pyrazolotriazines, pyrazolylthienopyridines, and 2-(pyrazolylamino)thiazol-4-ones, utilizing 3-amino-5-methyl-1H-pyrazole as a synthetic precursor. Their in vitro anticancer activity was tested on hepatocellular carcinoma cell line, HepG2. The results revealed that the pyrazolylhydrazonoyl cyanide 8, the pyrazolopyrimidine 3, and the pyrazolylaminothiazolone 17 were the most active with IC50 values of 2, 7, and 7 µM respectively in comparison with 5.5 µM for cisplatin as a reference drug. Interestingly, all the synthesized compounds showed higher selectivity index than cisplatin. DNA binding assay was also carried out for the synthesized compounds to rationalize their mechanism of action. Molecular modeling studies, including docking into DNA minor groove, flexible alignment, and surface mapping, were conducted. Results obtained proved the superior DNA-binding affinity of the most active anticancer compounds.

Synthesis of Pyridine-Dicarboxamide-Cyclohexanone Derivatives: Anticancer and α-Glucosidase Inhibitory Activities and In Silico Study.

An efficient and practical method for the synthesis of 2,6-diaryl-4-oxo-N,N'-di(pyridin-2-yl)cyclohexane-1,1-dicarboxamide is described in this present study, which occurs through a double Michael addition reaction between diamide and various dibenzalacetones. The reaction was carried out in dichloromethane (DCM) in the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). The anticancer activities of the synthesized compounds were evaluated in several cancer cell lines, including MCF-7, MDA-MB-231, SAS, PC-3, HCT-116, HuH-7 and HepG2 cells. From these experiments, we determined that MDA-MB-231 was the most sensitive cancer cell line to the compounds 3c, 3e, 3d, 3j and 3l, which exhibited variable anticancer activities (3l [IC50 = 5 ± 0.25 µM] > 3e [IC50 = 5 ± 0.5 µM] > 3c [IC50 = 7 ± 1.12 µM] > 3d [IC50 = 18 ± 0.87 µM] > 3j [IC50 = 45 ± 3 µM]). Of these, 3l (substituted p-trifluoromethylphenyl and chloropyridine) showed good potency (IC50 = 6 ± 0.78 µM) against HCT-116 colorectal cancer cells and exhibited high toxicity against HuH-7 liver cancer cells (IC50 = 4.5 ± 0.3 µM). These values were three times higher than the values reported for cisplatin (IC50 of 8 ± 0.76 and 14.7 ± 0.5 µM against HCT-116 and HuH-7 cells, respectively). The highest α-glucosidase inhibitory activity was detected for the 3d, 3i and 3j compounds. The details of the binding mode of the active compounds were clarified by molecular docking studies.