Fabrication and characterization of unique sustain modified chitosan nanoparticles for biomedical applications.

Chitosan (CS) is a biopolymer that offers a wide range in biomedical applications due to its biocompatibility, biodegradability, low toxicity and antimicrobial activity. Syringaldehyde (1) is a naturally occurring organic compound characterized by its use in multiple fields such as pharmaceuticals, food, cosmetics, textiles and biological applications. Herein, development of chitosan derivative with physicochemical and anticancer properties via Schiff base formation from the reaction of chitosan with sustainable eco-friendly syringaldehyde yielded the (CS-1) derivative. Moreover, in the presence of polyethylene glycol diglycidyl ether (PEGDGE) or sodium tripolyphosphate (TPP) as crosslinkers gave chitosan derivatives (CS-2) and (CS-3NPs) respectively. The chemical structures of the new chitosan derivatives were confirmed using different tools. (CS-3NPs) nanoparticle showed improvement in crystallinity, and (CS-2) derivative revealed the highest thermal stability compared to virgin chitosan. The cytotoxicity activity of chitosan and its derivatives were evaluated against HeLa (human cervical carcinoma) and HEp-2 (Human Larynx carcinoma) cell lines. The highest cytotoxicity activity was exhibited by (CS-3NPs) compared to virgin chitosan against HeLa cell growth inhibition and apoptosis of 90.38 ± 1.46% and 30.3% respectively and IC50 of 108.01 ± 3.94 µg/ml. From the above results, it can be concluded that chitosan nanoparticle (CS-3NPs) has good therapeutic value as a potential antitumor agent against the HeLa cancer cell line.

GC-MS profiling and evaluation of acute oral toxicity, anti-tumour, antimicrobial and antioxidant activities of Croton socotranus Balf.f. aerial parts: in-vitro, in-vivo and in-silico studies.

Croton socotranus Balf.f. shrub is widely used traditionally in Asia as an anti-infective. The study was conducted for metabolite profiling, oral acute toxicity and antioxidant studies, antimicrobial activity and anticancer effect against human hepatoma (HepG2), breast cancer (MCF-7) and rhabdomyosarcoma (RD) cells. Gas chromatography-mass spectrometry analysis revealed the presence of 39 compounds, predominantly comprising fatty acids (57.76%), sesquiterpenes (24.56%) and triterpenes (9.54%). The n-hexane fraction exhibited promising antimicrobial activity and displayed a potent anti-tumour effect against HepG2, MCF-7 and RD cells with IC50 values of 3.4, 6.5 and 7.1 µg/mL, respectively. Histological examination revealed significant morphological changes consistent with the changes observed in the apoptotic mechanism of action. The molecular docking study provided insights into the rational binding modes of the identified compounds with phosphoinositide 3-kinase and poly(ADP-ribose)polymerase-1 enzymes. Our findings suggest the potential of C. socotranus as a valuable source of antimicrobial and anticancer agents.

Novel landmarks on the journey from natural products to pharmaceutical formulations: Phytochemical, biological, toxicological and computational activities of Satureja hortensis L.

This study examined the ethanolic extract of the Satureja hortensis L. plant's aerial parts to describe its phytochemical makeup, biological functions, toxicity tests, and in-silico molecular docking tests. The GC-MS analysis was used to evaluate the phytochemical composition of the tested extract, and the ABTS and hydrogen peroxide antioxidant assays were used to measure antioxidant activity. Aspergillus fumigatus, Candida albicans, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, and Proteus vulgaris were tested for antimicrobial potential. On cell lines such as HepG-2, MCF-7, A-549, and Panc-1, the in-vitro toxicity was also examined. The A-549 cell line was also used for flow cytometry analysis of apoptosis and cell cycle. Additionally, the compounds discovered by the GC-MS analysis were used in silico tests against biological targets. Eight different phytocompounds were tentatively identified as a result of the GC-MS analysis. The compounds also demonstrated significant antioxidant potential for the ABTS and H2O2 assays (IC50: 2.44 and 28.04 µg/ml, respectively). The tested extract was found to have a range of inhibition zones and to be significantly active against the tested bacterial and fungal strains. Apoptosis and cell cycle analysis for the A-549 cell line showed that the cell cycle was arrested at S-phase, and the extract was also found to be most active against this cell line with an IC50 value of 113.05 µg/ml. The docking studies have emphasized the compounds' interactions and binding scores with the EGFR-TK target as determined by the GC-MS.

In Vitro Antibacterial and Phytochemical Screening of Hypericum perforatum Extract as Potential Antimicrobial Agents against Multi-Drug-Resistant (MDR) Strains of Clinical Origin.

Background: The perennial plant Hypericum perforatum is widely distributed around the world. It has been used for many years in conventional medicine to treat a variety of illnesses, including stress, mild to moderate depression, and minor injuries. This study examined the antimicrobial activity of the H. perforatum total extract and its fractions (n-hexane, ethyl acetate, chloroform, and aqueous) against multi-drug-resistant (MDR) isolates that were gathered from clinical samples, including methicillin-resistant Staphylococcus aureus (MRSA), Enterococcus faecalis, Escherichia coli, and Klebsiella pneumonia. Materials and Methods: Aerial parts of H. perforatum were collected and extracted using various solvents and were tested versus different isolated bacterial species. The inhibition zone of tested extracts was detected using an agar diffusion assay, and MICs were measured. Phytochemical analysis of promising H. perforatum extract was done using LC-ESI-MS/MS. Ultrastructure examination for the most altered bacteria used transmission electron microscopy. Antioxidant assays were done using DPPH and ABTS scavenging capacity methods. Cytotoxicity was reported versus Vero cells. Results: Different extracts of H. perforatum showed promising antibacterial activity against the pathogens. While the subfractions of the total extract were observed to show lesser inhibition zones and higher MIC values than the total extract of H. perforatum against MDR strains, the total extract of H. perforatum demonstrated the most potent antimicrobial action with an inhibition zone range of 17.9-27.9 mm. MDR-K. pneumoniae was discovered to be the most susceptible strain, which is consistent with the antibacterial inhibitory action of H. perforatum whole extract. Additionally, after treatment at the minimum inhibitory concentration (MIC 3.9 µg/ml), the transmission electron microscope showed alterations in the ultrastructure of the K. pneumoniae cells. Methanol extract from H. perforatum has a CC50 value of 976.75 µg/ml. Conclusion: Future inhibitors that target MDR strains may be revealed by these findings. Additionally, the extracts that were put to the test demonstrated strong antioxidant effects as shown by DPPH or ABTS radical-scavenging assays.

Evaluation of acute oral toxicity, anti-diabetic and antioxidant effects of Aloe vera flowers extract.

ETHNOPHARMACOLOGICAL RELEVANCE: Aloe vera (L.) Burm.f. is widely used in various traditional systems of medicine worldwide. Since over 5000 years ago, several cultures have used A. vera extract medicinally for conditions ranging from diabetes to eczema. It has been shown to reduce the symptoms of diabetes by enhancing insulin secretion and protecting pancreatic islets. AIM OF THE WORK: This research study aimed to investigate the in-vitro antioxidant effect, the acute oral toxicity, and the possible pharmacological in-vivo anti-diabetic activity with histological examination of the pancreas of the standardized deep red A. vera flowers methanolic extracts (AVFME). MATERIALS AND METHODS: The liquid-liquid extraction procedure and TLC technique were used to investigate chemical composition. Total phenolics and flavonoids in AVFME were quantified by Folin-Ciocalteu and AlCl3 colorimetric methods, respectively. The present study involved evaluating the in-vitro antioxidant effect of AVFME using ascorbic acid as the reference standard, an acute oral toxicity study by using thirty-six albino rats and different concentrations of AVFME (200 mg/kg, 2, 4, 8 and 10 g/kg b.w.). Furthermore, the in-vivo anti-diabetic study was performed on alloxan-induced diabetes in rats (120 mg/kg, I.P.) and two doses of AVFME (200 and 500 mg/kg b.w., orally) were used as compared to glibenclamide (5 mg/kg, orally) as a standard hypoglycemic sulfonylurea medication. A histological examination of the pancreas was performed. RESULTS: AVFME resulted in the highest phenolic content of 150.44 ± 4.62 mg gallic acid equivalent per gram (GAE/g) along with flavonoid content of 70.38 ± 0.97 mg of quercetin equivalent per gram (QE/g). An in-vitro study revealed that the antioxidant effect of AVFME was strong as ascorbic acid. The results of the in-vivo studies showed that the AVFME didn't cause any apparent toxicity signs or death in all groups at different doses which proves the safety of this extract with a wide therapeutic index. The antidiabetic activity of AVFME demonstrated a considerable drop in blood glucose levels as glibenclamide, without severe hypoglycemia or significant weight gain which is considered an advantage of AVFME over glibenclamide use. The histopathological study of pancreatic tissues confirmed the protective effect of AVFME on the pancreatic beta-cells. The extract is proposed to have antidiabetic activity through inhibition of α-amylase, α-glucosidase, and dipeptidyl peptidase IV (DPP-IV). Molecular docking studies were conducted to understand possible molecular interactions with these enzymes. CONCLUSION: AVFME represents a promising alternative source of active constituents against diabetes mellitus (DM) based on its oral safety, antioxidant, anti-hyperglycemic activities, and pancreatic protective effects. These data revealed the antihyperglycemic activity of AVFME is mediated by pancreatic protective effects while significantly enhancing insulin secretion through increasing functioning beta cells. This suggests that AVFME has the potential as a novel antidiabetic therapy or a dietary supplement for the treatment of type 2 diabetes (T2DM).

Design, synthesis and antimicrobial assessments of aminoacetylenic-piperazine nitroimidazole hybrid compounds.

A new series of aminoacetylenic nitroimidazole piperazine hybrid compounds were prepared via three-component reaction. Mannich-type reaction was utilized to couple the nitroimidazole containing propargylic moiety with secondary amines and formaldehyde in the presence of Cu (I) catalyst. The newly synthesized molecules 10a-10w, were characterized an ambiguously through NMR and mass spectrometry. The prepared compounds were assessed in vitro for their antibacterial activity against selected gram-positive and gram-negative bacteria. All of the compounds had shown insignificant activities toward gram-negative bacteria. While compounds 10m, 10q, 10s and 10t had shown moderate activities against the gram-positive bacteria Staphylococcus aureus, Bacillus subtilis and against fungi Escherichia coli and Proteus vulgaris.

Discovery of novel thiazolyl-pyrazolines as dual EGFR and VEGFR-2 inhibitors endowed with in vitro antitumor activity towards non-small lung cancer.

New series of thiazolyl-pyrazoline derivatives (7a-7d, 10a-10d and 13a-13f) have been synthesised and assessed for their potential EGFR and VEGFR-2 inhibitory activities. Compounds 10b and 10d exerted potent and selective inhibitory activity towards the two receptor tyrosine kinases; EGFR (IC50 = 40.7 ± 1.0 and 32.5 ± 2.2 nM, respectively) and VEGFR-2 (IC50 = 78.4 ± 1.5 and 43.0 ± 2.4 nM, respectively). The best anti-proliferative activity for the examined thiazolyl-pyrazolines was observed against the non-small lung cancer cells (NSCLC). Compounds 10b and 10d displayed pronounced efficacy against A549 (IC50 = 4.2 and 2.9 µM, respectively) and H441 cell lines (IC50 = 4.8 and 3.8 µM, respectively). Moreover, our results indicated that 10b and 10d were much more effective towards EGFR-mutated NSCLC cell lines (NCI-H1650 and NCI-H1975 cells) than gefitinib. Finally, compounds 10b and 10d induce G2/M cell cycle arrest and apoptosis and inhibit migration in A549 cancerous cells.

Determination of Therapeutic and Safety Effects of Zygophyllum coccineum Extract in Induced Inflammation in Rats.

Background: Z. coccineum is a facultative plant with many medicinal applications. This study examined the anti-inflammatory activity of Zygophyllum coccineum (Z. coccineum) in an arthritis animal model. Materials and Methods: Seventy-Six Wistar Albino rats of either sex randomly divided into six groups (12/each). The inflammation model was done using Complete Freund's Adjuvant in albino rats. The anti-inflammatory activities of the extract were estimated at different dose levels (15.6, 31, and 60 mg/kg) as well as upon using methotrexate (MTX) as a standard drug (0.3 mg/kg). Paw volume and arthritis index scores have been tested in all examined animals' treatments. Histological examination of joints was also performed. Flow cytometric studies were done to isolated osteoclasts. Cytokines assay as well as biochemical testing was done in the examined samples. Results. In vitro studies reported an IC50 of 15.6 µg/ml for Z. coccineum extract in lipoxygenase inhibition assay (L.O.X.). Moreover, it could be noticed that isorhamnetin-3-O-glucoside, tribuloside, and 7-acetoxy-4-methyl coumarin were the most common compounds in Z. coccineum extract separated using L.C.-ESI-TOF-M.S. (liquid chromatography-electrospray ionization ion-trap time-of-flight mass spectrometry). Microscopic examinations of synovial tissue and hind limb muscles revealed the effect of different doses of Z. coccineum extract on restoring chondrocytes and muscles structures. Osteoclast size and apoptotic rate examinations revealed the protective effect of Z. coccineum extract on osteoclast. The results upon induction of animals and upon treatment using of MTX significantly increased apoptotic rate of osteoclast compared to control, while using of 15.6 µg/ml. for Z. coccineum extract lead to recover regular apoptotic rate demonstrating the protective effect of the extract. Z. coccineum extract regulated the secretion of proinflammatory and anti-inflammatory cytokines. Biochemical tests indicated the safety of Z. coccineum extract on kidney and liver functions. Conclusion. Z. coccineum extract has efficient and safe anti-inflammatory potential in an induced rat model.

Evaluation of Pleotropic Protective Activity of Capparis spinose Extract on Arthritis Rat Model.

BACKGROUND: Capparis spinosa grows in Asian and Mediterranean desert areas. Different parts of Capparis spinosa, including flowers, have been used in various folk medicine applications. OBJECTIVE: This study aims to evaluate the anti-arthritic potential of ethanolic extract of Egyptian Capparis spinosa flowers in a rat model of rheumatoid arthritis. Moreover, analysis of Capparis spinosa extract was performed using LC-qTOF-MS/MS. METHODS: Animals were split into six groups: negative control group, induced arthritic animals, arthritic rats receiving 7, 14 and 28 mg/kg of Capparis spinosa extract, respectively, in three groups to detect the optimum dose, and the induced group receiving a standard drug. The arthritic score was checked daily for 15 days after induction. After animals were sacrificed, their joints and muscles were subjected to microscopic and ultra-structure examinations. Ex vivo culturing of osteoclasts was performed. Cytokine levels were measured in all examined groups. RESULTS: The results revealed 7 mg/kg of Capparis spinosa extract as the optimal dose, which decreased inflammation signs through controlling chondrocytes, osteoclasts, and levels of inflammatory mediators. CONCLUSION: LC-Mass analysis revealed Capparis spinosa extract to contain a mixture of flavonol glycosides, flavan-3-ols and hydroxycinnamic acid derivatives, which may provide beneficial multifunction in regulating arthritic symptoms.

Preliminary Study of Gastroprotective Effect of Aloe perryi and Date Palm Extracts on Pyloric Ligation-Induced Gastric Ulcer in Experimental Rats.

OBJECTIVE: The present study was aimed at investigating the possible antiulcer activities of some natural phytochemicals Aloe perryi leaf extract (APLE) and flower extract (APFE) in addition to the date palm seed extract (DPSE) and the oily samples of DPSE in a pylorus ligation-induced ulcer model using ranitidine as a standard antiulcer drug. BACKGROUND: Peptic ulcer is a prevalent gastrointestinal disorder due to hypersecretion of gastric acid. It affects four million people worldwide, and 2-10% of these ulcers are perforated and cause bleeding. This increases the risk of morbidity and mortality. So we aimed to introduce a primary study alternatively safe method for treating peptic ulcer. MATERIALS AND METHODS: Forty-two Wistar Albino rats of either sex were randomly divided into seven groups (6/each). The pylorus ligation was done to induce ulcer in pretreated albino rats. The antiulcer activities of extracts were estimated at different dose levels (250 and 500 mg/kg) using ranitidine as a standard drug (50 mg/kg). Gastric volume, pH, and total and free acidity as well as ulcer index and percentage of ulcer inhibition were measured to elucidate the antiulcerogenic effects. Histological examination of gastric ulcer was also performed. Statistical analysis for the results was done where P < 0.05 was considered statistically significant. RESULTS: Pylorus ligation for 6 h in control rats resulted in gastric ulcer which was indicated by the accumulation of gastric secretion and increased total acidity and decreased pH. The pretreatment of rats with APLE, APFE, and DPSE in addition to the oily samples of DPSE significantly inhibited the ulcers induced by pylorus ligation. These effects were attributed to significant reductions in total and free acidity, ulcer index, and gastric volume while there is a marked decrease in gastric pH (the antisecretory) as well as mucosal strengthening properties of these phytochemicals. CONCLUSION: These findings give these extracts the potential to be a promising tool for the management of gastric ulcer after performing further clinical and experimental studies. Our study demonstrated the promising antiulcer activity of extracts and oils in pyloric ligation-induced gastric ulcer. To the best of our knowledge, this is the first study to explore the antiulcer activity of these extracts; however, further investigations may be recommended for full details about this antiulcerogenic capacity.

Natural inspired ligustrazine-based SLC-0111 analogues as novel carbonic anhydrase inhibitors.

Ligustrazine is the principle bioactive alkaloid in the widely-used Chinese herb Chuan Xiong rhizome. Herein, a series of novel derivatives has been designed as human carbonic anhydrases inhibitors (hCAIs) starting from the natural product Ligustrazine inserted as a tail instead of the 4-fluorophenyl tail of SLC-0111, a front-runner selective hCA IX inhibitor currently in clinical trials as antitumor/antimetastatic agent. Other derivatives were designed via incorporation of different linkers, of amide and ester type, or incorporation of different zinc anchoring groups such as secondary sulfamoyl and carboxylic acid functionalities. The newly designed molecules were prepared following different synthetic pathways, and were assessed for their inhibitory actions against four isoforms: the widespread cytosolic (hCA I and II), and the transmembrane tumor-related (hCA IX and XII). The primary sulfonamides efficiently inhibited the target hCA IX and hCA XII in the nanomolar range (KIs: 6.2-951.5 nM and 3.3-869.3 nM, respectively). The most selective hCA IX inhibitors 6c and 18 were assessed for their potential anticancer effects, and displayed anti-proliferative activity against MCF-7 cancer cell line with IC50s of 11.9 and 36.7 µM, respectively. Molecular modelling studies unveiled the relationship between structural features and inhibitory profiles against the off-target hCA II and the target, tumor-related isoforms hCA IX and XII.

Development of isatin-thiazolo[3,2-a]benzimidazole hybrids as novel CDK2 inhibitors with potent in vitro apoptotic anti-proliferative activity: Synthesis, biological and molecular dynamics investigations.

In the current medical era, human health is experiencing numerous challenges, particularly the human malignancies. Therefore, the therapeutic arsenal for these malignancies is to be inexorably enhanced with new treatments that target tumor cells in a selective manner. In this regard, the present work aims at developing a new set of small molecules featuring the privileged isatin scaffold conjugated with a thiazolo[3,2-a]benzimidazole (TBI) motif through a cleavable hydrazide linker (7a-e and 10a-i) as potential anticancer CDK2 inhibitors. The large tricyclic TBI motif is anticipated to achieve a plethora of hydrophobic interactions within the CDK2 binding site. The growth of the two examined cell lines was significantly inhibited by most the prepared hybrids with IC50 ranges; (2.60 ± 1.47-20.90 ± 1.17 µM, against MDA-MB-231) and (1.27 ± 0.06-16.83 ± 0.95 µM, against MCF-7). In particular, hybrids 7a, 7d and 10a displayed potent dual activity against the examined cell lines, and thus selected for further investigations. They exerted a significance alteration in the cell cycle progression, in addition to an apoptosis induction within both MDA-MB-231 and MCF-7 cells. Furthermore, 7a, 7d and 10a displayed potent CDK2 inhibitory action (IC50 = 96.46 ± 5.3, 26.24 ± 1.4 and 42.95 ± 2.3 nM, respectively). The docking simulations unveiled, as expected, the ability of the TBI ring to well-accommodate and establish several hydrophobic interactions within a hydrophobic pocket in the CDK2 binding site. Also, the docking simulations highlighted the significance of incorporation of the hydrazide linker and isatin unsubstituted (NH) functionality in the H-bonding interactions. Interestingly, the most potent CDK2 inhibitor 7d achieved the best binding score (-11.2 Kcal/mole) and formed the most stable complex with CDK2 enzyme (RMSD = 1.24 Å) in a 100 ns MD simulation. In addition, the MM-PBSA calculations ascribed the lowest binding free energy to the 7d-CDK2 complex (-323.69 ± 15.17 kJ/mol). This could be attributed to an incorporation of the 5-OCH3 group that was engaged in an extra hydrogen bonding with key THR14 amino acid residue. Finally, these results suggested hybrid 7d as a good candidate for further optimization as promising breast cancer antitumor agent and CDK2 inhibitor.

Thiazole-Based Thiosemicarbazones: Synthesis, Cytotoxicity Evaluation and Molecular Docking Study.

INTRODUCTION: Hybrid drug design has developed as a prime method for the development of novel anticancer therapies that can theoretically solve much of the pharmacokinetic disadvantages of traditional anticancer drugs. Thus a number of studies have indicated that thiazole-thiophene hybrids and their bis derivatives have important anticancer activity. Mammalian Rab7b protein is a member of the Rab GTPase protein family that controls the trafficking from endosomes to the TGN. Alteration in the Rab7b expression is implicated in differentiation of malignant cells, causing cancer. METHODS: 1-(4-Methyl-2-(2-(1-(thiophen-2-yl) ethylidene) hydrazinyl) thiazol-5-yl) ethanone was used as building block for synthesis of novel series of 5-(1-(2-(thiazol-2-yl) hydrazono) ethyl) thiazole derivatives. The bioactivities of the synthesized compounds were evaluated with respect to their antitumor activities against MCF-7 tumor cells using MTT assay. Computer-aided docking protocol was performed to study the possible molecular interactions between the newly synthetic thiazole compounds and the active binding site of the target protein Rab7b. Moreover, the in silico prediction of adsorption, distribution, metabolism, excretion (ADME) and toxicity (T) properties of synthesized compounds were carried out using admetSAR tool. RESULTS: The results obtained showed that derivatives 9 and 11b have promising activity (IC50 = 14.6 ± 0.8 and 28.3 ± 1.5 µM, respectively) compared to Cisplatin (IC50 = 13.6 ± 0.9 µM). The molecular docking analysis reveals that the synthesized compounds are predicted to be fit into the binding site of the target Rab7b. In summary, the synthetic thiazole compounds 1-17 could be used as potent inhibitors as anticancer drugs. CONCLUSION: Promising anticancer activity of compounds 9 and 11 compared with cisplatin reference drug suggests that these ligands may contribute as lead compounds in search of new anticancer agents to combat chemo-resistance.

Synthesis of Novel Chalcone-Based Phenothiazine Derivatives as Antioxidant and Anticancer Agents.

Based on reported results for the potential medicinal impact of phenothiazine core, as well as the chalcone skeleton that is widely present in many natural products, together with their reported bioactivities, the present work was aimed at combining both moieties in one molecular skeleton and to synthesize and characterize a novel series of chalone-based phenothiazine derivatives. For this purpose, 2-acetylphenothiazine was N-alkylated, followed by the Claisen-Schmidt reaction to produce the chalcones with good yield. Antioxidant activity, as evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, was assessed to determine if their antioxidant potential was comparable with ascorbic acid, and attributable to the phenothiazine core. Screening anticancer activities of the synthesized chalone-based phenothiazine derivatives against human breast cancer cell line MCF-7 cells, and human hepatocellular carcinoma HepG-2 cells, compared with standard drugs cisplatin and doxorubicin, was evaluated. The results revealed that compounds 4a, 4b, 4d, 4h, 4j, 4k, 4m, 4o, and 4p were good against human hepatocellular carcinoma HepG-2 cells, and among these compounds 4b and 4k were the most effective compounds, with IC50 values of 7.14 µg/mL and 7.6 1 µg/mL, respectively. On the other hand, compounds 4a, 4b, 4k, and 4m were good against human breast cancer cell line MCF-7 cells and, among these compounds, 4k and 4b were the most effective compounds, with IC50 values of 12 µg/mL and 13. 8 µg/mL, respectively. The overall results suggest that these compounds could, potentially, be further modified for the formation of more potent antioxidant and anticancer agents.

Discovery of 3,6-disubstituted pyridazines as a novel class of anticancer agents targeting cyclin-dependent kinase 2: synthesis, biological evaluation and in silico insights.

Human health in the current medical era is facing numerous challenges, especially cancer. So, the therapeutic arsenal for cancer should be unremittingly enriched with novel small molecules that selectively target tumour cells with minimal toxicity towards normal cells. In this context, herein a new series of 3,6-disubstituted pyridazines 11a-r has been synthesised and evaluated for in vitro anticancer activity. They possessed good anti-proliferative action towards human breast cancer T-47D (IC50 range: 0.43 ± 0.01 - 35.9 ± 1.18 µM) and MDA-MB-231 (IC50 range: 0.99 ± 0.03 - 34.59 ± 1.13 µM) cell lines, whereas they displayed weak activity against the tested ovarian cancer cell line SKOV-3. Among the studied compounds, the methyltetrahydropyran-bearing pyridazine 11m emerged as the unique submicromolar growth inhibitor herein reported towards both T-47D (IC50 = 0.43 ± 0.01 µM) and MDA-MB-231 (IC50 = 0.99 ± 0.03 µM) cell lines. In addition, the biological results indicated that pyridazines 11l and 11m exerted an efficient alteration within the cell cycle progression as well as induction of apoptosis in both T-47D and MDA-MB-231 cells. Moreover, pyridazines 11l and 11m displayed good mean tumour S. I. values of 13.7 and 16.1 upon assessment of their cytotoxicity towards non-tumorigenic breast MCF-10A cells. Furthermore, an in silico study proposed CDK2 as a probable enzymatic target for pyridazines 11, and explored their binding interactions within the vicinity of CDK2 binding site. Subsequently, pyridazines 11e, 11h, 11l, and 11m were selected to be evaluated for their ability to inhibit CDK2, where they exerted good inhibitory activity (IC50 = 151, 43.8, 55.6 and 20.1 nM, respectively). Finally, the in silico study implied that target pyridazines 11 exhibited not only an efficient anticancer activity but also an acceptable ADME, physicochemical and druglikeness properties, specifically pyridazines 11l and 11m. Overall the obtained results from this study quite sustained our strategy and gave us a robust opportunity for further development and optimisation of 3,6-disubstituted pyridazine scaffold to enrich therapeutic arsenal with efficient and safe anticancer CDK inhibitors.

Novel [(N-alkyl-3-indolylmethylene)hydrazono]oxindoles arrest cell cycle and induce cell apoptosis by inhibiting CDK2 and Bcl-2: synthesis, biological evaluation and in silico studies.

As a continuation for our previous work, a novel set of N-alkylindole-isatin conjugates (7, 8a-c, 9 and 10a-e) is here designed and synthesised with the prime aim to develop more efficient isatin-based antitumor candidates. Utilising the SAR outputs from the previous study, our design here is based on appending four alkyl groups with different length (ethyl and n-propyl), bulkiness (iso-propyl) and unsaturation (allyl) on N-1 of indole motif, with subsequent conjugation with different N-unsubstituted isatin moieties to furnish the target conjugates. As planned, the adopted strategy achieved a substantial improvement in the growth inhibitory profile for the target conjugates in comparison to the reported lead VI. The best results were obtained with N-propylindole -5-methylisatin hybrid 8a which displayed broad spectrum anti-proliferative action with efficient sub-panel GI50 (MG-MID) range from 1.33 to 4.23 µM, and promising full-panel GI50 (MG-MID) equals 3.10 µM, at the NCI five-dose assay. Also, hybrid 8a was able to provoke cell cycle disturbance and apoptosis in breast T-47D cells as evidenced by the DNA flow cytometry and Annexin V-FITC/PI assays. Furthermore, hybrid 8a exhibited good inhibitory action against cell cycle regulator CDK2 protein kinase and the anti-apoptotic Bcl-2 protein (IC50= 0.85 ± 0.03 and 0.46 ± 0.02 µM, respectively). Interestingly, molecular docking for hybrid 8a in CDK2 and Bcl-2 active sites unveiled that N-propyl group is involved in significant hydrophobic interactions. Taken together, the results suggested conjugate 8a as a promising lead for further development and optimisation as an efficient antitumor drug.

3-Hydrazinoisatin-based benzenesulfonamides as novel carbonic anhydrase inhibitors endowed with anticancer activity: Synthesis, in vitro biological evaluation and in silico insights.

Herein we describe the design and synthesis of two series of sulfonamides featuring N-unsubstituted (4a-c) or N-substituted (7a-o) isatin moieties (as tails) connected to benzenesulfonamide moiety via a hydrazine linker. All the prepared sulfonamides (4a-c and 7a-o) showed potent inhibitory activities toward transmembrane tumor-associated human (h) carbonic anhydrase (hCA, EC 4.2.1.1) isoforms, IX and XII with KI range (8.3-65.4 nM) and (11.9-72.9 nM), respectively. Furthermore, six sulfonamides (7e, 7i, 7j, 7m, 7n and 7o) were assessed for their anti-proliferative activity, according to US-NCI protocol, toward a panel of sixty cancer cell lines. Compounds 7j and 7n were the most promising counterparts in this assay displaying broad spectrum anti-proliferative activity toward diverse cell lines. Also, sulfonamide 7n significantly inhibited clonogenicity of HCT-116 cells in a concentration dependent manner in the colony forming assay. Moreover, molecular modeling studies were performed to gain insights for the plausible binding interactions and affinities for the target isatin-based sulfonamides (4a-c and 7a-o) within hCA isoforms II and IX active sites.

New thiobarbituric acid scaffold-based small molecules: Synthesis, cytotoxicity, 2D-QSAR, pharmacophore modelling and in-silico ADME screening.

A series of twenty five new thiobarbituric acid derivatives, viz. 3a-h, 4-7, 8a-c, 9, 10a-c, 11 and 12a-d, were designed and synthesized as potential cytotoxic agents. In-vitro screening of the new compounds against the three human cancer cell lines Caco-2, HepG-2 and MCF-7 was performed to assess their intrinsic activity. Compound 12d exhibited potent sub-micromolar activity against HepG-2 and MCF-7 (IC50 = 0.07 and 0.08 µM, respectively). In-silico pharmacophore modelling of this chemotype compounds disclosed a five features' pharmacophore model representing essential steric and electronic fingerprints essential for activity. Finally, a 2D-QSAR model was devised to quantitatively correlate the 2D molecular feature descriptors of this series of thiobarbiturates with their cytotoxic activity against MCF-7. Finally, in silico evaluation of the physicochemical and ADME properties of these derivatives was performed.

One-pot synthesis of spiro(indoline-3,4'-pyrazolo[3,4-b]pyridine)-5'-carbonitriles as p53-MDM2 interaction inhibitors.

AIM: Inhibition of P53-mdm2 interaction will lead to cancer cell apoptosis. This strategy was achieved by reported spiro-oxindole derivatives. MATERIALS & METHODS: Spiro(indoline-3,4'-pyrazolo[3,4-b]pyridine)-5'-carbonitrile derivatives (4a-i and 9a, b) were synthesized and screened for their in vitro anticancer activity. The most active compounds were subjected to P53-MDM2 inhibitory activity, apoptotic and molecular docking studies. RESULTS & DISCUSSION: Compound 4d exhibited potent and broad spectrum of antiproliferative activity with full panel GI50 (MG-MID) value of 3.97 µM. Compounds 4d and 4i inhibited p53-MDM2 protein-protein interaction with IC50 = 52.1 and 95.2 nM, respectively. Compound 4d inhibits the expression of wild p53 in MCF-7 more than mutant p53 in MDA-MB231 at the molecular level. Molecular docking studies illustrated the possible interaction of the target spiro-oxindoles with the p53 binding site on MDM2.

Novel indole-thiazolidinone conjugates: Design, synthesis and whole-cell phenotypic evaluation as a novel class of antimicrobial agents.

In connection with our research program on the development of novel anti-tubercular candidates, herein we report the design and synthesis of two different sets of indole-thiazolidinone conjugates (8a,b; 11a-d) and (14a-k; 15a-h). The target compounds were evaluated for their in vitro antibacterial and antifungal activities against selected human pathogens viz. Staphylococcus aureus (Gram positiveve), Pseudomonas aeruginosa, Escherichia coli (Gram negative), Mycobacterium tuberculosis (Acid-fast bacteria), Aspergillus fumigates and Candida albicans (fungi). Moreover, eukaryotic cell-toxicity was tested via an integrated ex vivo drug screening model in order to evaluate the selective therapeutic index (SI) towards antimicrobial activity when microbes are growing inside primary immune cells. Also, the cytotoxicity towards a panel of cancer cell lines and human lung fibroblast normal cell line, WI-38 cells, was explored to assure their safety. Compound 15b emerged as a hit in this study with potent broad spectrum antibacterial (MIC: 0.39-0.98 µg/mL) and antifungal (MIC: 0.49-0.98 µg/mL) activities, in addition to its ability to kill mycobacteria M. aurum inside an infected macrophage model with good therapeutic window. Moreover, compound 15b displayed promising activity towards resistant bacteria strains MRSA and VRE with MIC values equal 3.90 and 7.81 µg/mL, respectively. These results suggest compound 15b as a new therapeutic lead with good selectivity for further optimization and development.