Design, Synthesis and Docking Studies of Novel Macrocyclic Pentapeptides as Anticancer Multi-Targeted Kinase Inhibitors

Synthesis and Molecular Docking of some new Thiazolidinone and Thiadiazole Derivatives as Anticancer Agents

New sets of functionalized thiazolidinone and thiadiazole derivatives were synthesized, and their cytotoxicity was evaluated on HepG2, MCF-7, HTC-116, and WI38 cells. The synthetic approach is based on the preparation of 4-(4-acetamidophenyl)thiosemicarbazide (4) and their thiosemicarbazones 5 a-e, which are converted to the corresponding thiazoldin-4-one compounds 6 a-e upon cyclization with ethyl bromoacetate. The thiadiazole compounds 9 and 12 were obtained by reacting 4-(4-acetamidophenyl)thiosemicarbazide with isothiocyanates and/or ethyl 2-cyano-3,3-bis(methylthio)acrylate, respectively. The thiazolidinone compounds 6 c and 6 e exhibited strong cytotoxicity against breast cancer cells, with an IC50 (6.70±0.5 μM) and IC50 (7.51±0.8 μM), respectively, very close to that of doxorubicin (IC50: 4.17±0.2 μM). In addition, the anti-cancer properties of the tested thiazolidinone and thiadiazole scaffolds were further explored by the molecular docking program (MOE)-(PDB Code-1DLS). Compounds 5 d, 5 e, 6 d, 6 e, and 7 have the best binding affinity, ranging from -8.5386 kcal.mol-1 to -8.2830 kcal.mol-1.

Synthesis, structural, multitargeted molecular docking analysis of anti-cancer, anti-tubercular, DNA interactions of benzotriazole based macrocyclic ligand

Biologically important macromolecule 1, 1', 3, 3' Bis - [2,3,5,6-Tetramethyl-p-phenylenebis(methylene)] dibenzotriazlinium dibromide hydrate (BTD) was synthesized and characterized using FT-IR, NMR and single-crystal XRD (SCXRD). SCXRD revealed that the compound was crystallized as a monoclinic system and associated through weak intermolecular interactions like H-bonding and π- π stacking interactions. These weak intermolecular interactions in BTD were studied using Crystal Explorer and Gaussian. The calculated energies for the Highest Occupied Molecular Orbital (HOMO) and the Lowest Unoccupied Molecular Orbital (LUMO) showed the stability and reactivity of the title compound. Molecular electrostatic potential (MEP) surface analysis was used to investigate the crystal's nucleophilic and electrophilic reactive sites. The molecular shape and intermolecular interactions in the crystal structure were determined using Hirshfeld surface analysis and fingerprint plots. Anticancer, anti-bacterial and DNA binding ability of BTD were investigated by experimental and theoretical techniques. The obtained results suggest that BTD possesses better anti-cancer, anti-bacterial and DNA binding abilities. The mode of action of antibiotic and anticancer approach was discussed. This provides promising therapeutic advantages for further development.

Non-enzymatic paper-based analytical device for direct potentiometric detection of urine creatinine

A paper-based analytical device (PAD) with an integrated composite electrode has been designed and fabricated for non-enzymatic creatinine sensing. Reduced graphene oxide (rGO) was employed to modify the PAD so that it could function as a solid-contact transducer. A new macrocyclic pyrido-hexapeptide derivative was made and used as a special ionophore in the creatinine membrane sensor. The synthesized PAD showed a detection limit of 1.0 µM (S/N = 3) and a potentiometric response towards creatinine throughout a log-linear range of 2.0 µM-10 mM (R2 = 0.9998). The sensor shows significant selectivity for a few related substances, including ephedrine, codeine, ketamine, caffeine, urea, urate, carbinoxamine, and dextromethorphan. It has been established that the testing method is appropriate for the direct potentiometric detection of creatinine in a variety of human urine sample types. When an indicating electrode and a reference electrode are put on the same flexible disposable, this lets applications with a small sample volume be done. For point-of-care creatinine measurement, the developed paper-based analytical equipment is a good choice because it is affordable, easily accessible, and self-pumping (especially when combined with potentiometric detection).

Paper-Based Analytical Device Based on Potentiometric Transduction for Sensitive Determination of Phenobarbital

In medicine, barbiturates are a class of depressive medications used as hypnotics, anticonvulsants, and anxiolytics. For the treatment of specific forms of epilepsy and seizures in young children in underdeveloped countries, the World Health Organization recommends phenobarbital (PBAR), a barbiturate drug. This review describes the fabrication and characterization of a paper-based analytical apparatus for phenobarbital detection that is straightforward, affordable, portable, and disposable. All of the solid-state ion-selective electrodes (ISEs) for PBAR as well as a Ag/AgCl reference electrode were constructed and optimized on a nonconductive paper substrate. Using carbon nanotube ink, the sensors were made to function as an ion-to-electron transducer and to make the paper conductive. A suitable polymeric membrane is drop-cast onto the surface of the carbon ink orifice. The pyrido-tetrapeptide and pyrido-hexapeptide derivatives, which were recently synthesized, functioned as distinct ionophores in the PBAR-membrane sensor, enabling its detection. With a detection limit of 5.0 × 10-7 M, the manufactured analytical device demonstrated a Nernstian response to PBAR anions in 50 mM phosphate buffer, pH 8.5, over a linear range of 1.0 × 10-6 to 1.0 × 10-3 M. The PBAR-based sensors showed quick (less than 5 s) response times for PBAR ion detection. The modified separate solution method was utilized to evaluate the selectivity pattern of these novel ionophores with respect to PBAR ions in comparison to other common anions. The analytical instrument that was exhibited on paper had good precision both within and between days. The suggested technology assisted in the detection of trace amounts of PBAR in real pharmaceutical samples. A comparison was made between the data acquired using the HPLC reference method and the information obtained by the recommended potentiometric approach. The described paper-based analytical device may be a good choice for point-of-care PBAR determination because it is cheap and easy to find and can self-pump (especially when combined with potentiometric detection).

Plant Flavonoids on Oxidative Stress-Mediated Kidney Inflammation

The kidney is susceptible to reactive oxygen species-mediated cellular injury resulting in glomerulosclerosis, tubulointerstitial fibrosis, tubular cell apoptosis, and senescence, leading to renal failure, and is a significant cause of death worldwide. Oxidative stress-mediated inflammation is a key player in the pathophysiology of various renal injuries and diseases. Recently, flavonoids' role in alleviating kidney diseases has been reported with an inverse correlation between dietary flavonoids and kidney injuries. Flavonoids are plant polyphenols possessing several health benefits and are distributed in plants from roots to leaves, flowers, and fruits. Dietary flavonoids have potent antioxidant and free-radical scavenging properties and play essential roles in disease prevention. Flavonoids exert a nephroprotective effect by improving antioxidant status, ameliorating excessive reactive oxygen species (ROS) levels, and reducing oxidative stress, by acting as Nrf2 antioxidant response mediators. Moreover, flavonoids play essential roles in reducing chemical toxicity. Several studies have demonstrated the effects of flavonoids in reducing oxidative stress, preventing DNA damage, reducing inflammatory cytokines, and inhibiting apoptosis-mediated cell death, thereby preventing or improving kidney injuries/diseases. This review covers the recent nephroprotective effects of flavonoids against oxidative stress-mediated inflammation in the kidney and their clinical advancements in renal therapy.

Click chemistry based synthesis, cytotoxic activity and molecular docking of novel triazole-thienopyrimidine hybrid glycosides targeting EGFR

In the current study, new thienopyrimidine conjugates bearing 1,2,3-triazole core and different sugar moieties have been designed and synthesized by Cu(I)-catalysed click dipolar cycloaddition. The cytotoxic activity of the synthesised conjugates 2, 5, 7, and 13-18 was studied against HCT-116 and MCF-7 cell lines by the MTT assay. The triazole glycosides 16 and 18 provided significant cytotoxic activities against HCT-116 cell lines comparable to that of doxorubicin and other studied compounds. The cytotoxic behaviour against MCF-7 exhibited that all the investigated compounds were more potent than doxorubicin. Moreover, all screened targets were evaluated against mutant EGFR kinase type L858R and the results revealed that the acetylated 1,2,3-triazole glycosides 13-18 exhibited excellent EGFR inhibitory activity in comparison with gefitinib. Furthermore, molecular modelling studies were performed to investigate the binding affinity of the most active compounds to EGFR enzyme.

Antibacterial activity of endosymbiotic bacterial compound from Pheretima sp. earthworms inhibit the growth of Salmonella Typhi and Staphylococcus aureus: in vitro and in silico approach

Background and Objectives:

Earthworms coexist with various pathogenic microorganisms; thus, their immunity mechanisms have developed through a long process of adaptation, including through endogenous bacterial symbionts. This study aims to identify earthworm endosymbiont bacteria compounds and their antibacterial activity through an in vitro approach supported by an in silico approach.

Materials and Methods:

This research was conducted using the in vitro inhibition test through agar diffusion and the in silico test using molecular docking applications, namely, PyRx and Way2Drugs Prediction of Activity Spectra for Substances (PASS).

Results:

The in vitro results showed a potent inhibition activity with a clear zone diameter of 21.75 and 15.5 mm for Staphylococcus aureus and Salmonella Typhi, respectively. These results are supported by chromatography and in silico tests, which showed that several compounds in endosymbiotic bacteria, cyclo (phenylalanyl-prolyl) and sedanolide, have high binding affinity values with several antibiotic-related target proteins in both pathogenic bacteria. Cyclo (phenylalanyl-prolyl) has the highest binding affinity of −6.0 to dihydropteroate synthase, −8.2 to topoisomerase, and −8.2 to the outer membrane, whereas sedanolide has the highest binding affinity to DNA gyrase with approximately −7.3. This antibiotic activity was also clarified through the Way2Drugs PASS application.

Conclusion:

Ten active compounds of endosymbiont bacteria, Cyclo (phenylalanyl-prolyl) and sedanolide were potential candidates for antibacterial compounds based on the inhibition test of the agar diffusion method and the results of reverse docking and Way2Drugs PASS.

Low-cost potentiometric paper-based analytical device based on newly synthesized macrocyclic pyrido-pentapeptide derivatives as novel ionophores for point-of-care copper(ii) determination

A simple, cost-effective, portable and disposable paper-based analytical device is designed and fabricated for copper(ii) determination. All solid-state ion-selective electrodes (ISEs) for copper and a Ag/AgCl reference electrode were constructed and optimized on the paper substrate. The copper electrodes were built using carbon nano-tube ink as a conductive substrate and an ion-to electron transducer. A suitable polymeric membrane is drop-cast on the surface of the conductive carbon ink window. The copper-sensing membrane is based on newly synthesized macrocyclic pyrido-pentapeptide derivatives as novel ionophores for copper detection. Under the optimized conditions, the presented all-solid-state paper-based Cu²⁺-ISEs showed a Nernstian response toward Cu²⁺ ions in 30 mM MES buffer, pH 7.0 over the linear range of 5.0 × 10⁻⁷–1.0 × 10⁻³ M with a limit of detection of 8.0 × 10⁻⁸ M. The copper-based sensors exhibited rapid detection of Cu²⁺ ions with a short response time (<10 s). The selectivity pattern of these new ionophores towards Cu²⁺ ions over many common mono-, di- and trivalent cations was evaluated using the modified separate solution method (MSSM). The presented paper-based analytical device exhibited good intra-day and inter day precision. The presented tool was successfully applied for trace Cu²⁺ detection in real samples of serum and whole blood collected from different children with autism spectrum disorder. The data obtained by the proposed potentiometric method were compared with those obtained by the inductively-coupled plasma (ICP) as a reference method. The presented copper paper-based analytical-device can be considered as an attractive tool for point-of-care copper determination because of its affordability, vast availability, and self-pumping ability, particularly when combined with potentiometric detection.

A simple, cost-effective, portable and disposable paper-based analytical device is designed and fabricated for copper(ii) determination.

Nα-1, 3-Benzenedicarbonyl-Bis-(Amino Acid) and Dipeptide Candidates: Synthesis, Cytotoxic, Antimicrobial and Molecular Docking Investigation

Purpose

The objective of our work was to prepare a potent and safe antimicrobial and anticancer agents, through synthesis of several peptides and examine their biological activities, namely as, cytotoxically potent and antimicrobial and antifungal agents.

Introduction

Multidrug-resistant microbial strains have arisen against all antibiotics in clinical use. Infections caused by these bacteria threaten global public health and are associated with high mortality rates.

Methods

The main backbone structure for the novel synthesized linear peptide is Nα-1, 3-benzenedicarbonyl-bis-(Amino acids)-X, (3–11). A computational docking study against DNA gyrase was performed to formulate a mode of action of the small compounds as antimicrobial agents.

Results

The peptide-bearing methionine-ester (4) exhibited potent antimicrobial activity compared to the other synthesized compounds, while, peptide (8), which had methionine-hydrazide fragment was the most potent as antifungal agent against Aspergillus niger with 100% inhibition percent. Compounds (6 and 7) showed the highest potency against breast human tumor cell line “MCF-7” with 95.1% and 79.8% of cell inhibition, respectively. The nine compounds possessed weak to moderate antiproliferative effect over colon tumor cell line. The docking results suggest good fitting through different hydrogen bond interactions with the protein residues. In silico ADMET study also evaluated and suggested that these compounds had promising oral bioavailability features.

Conclusion

The tested compounds need further modification to have significant antimicrobial and antitumor efficacy compared to the reference drugs.

Synthesis and Characterization of Macrocyclic Chiral Tröger's Base Phenhomazine Candidates as Anticancer Agent

1,4,7,10-Tetraoxa[10](2,8)trögerophane 5 was synthesized from its corresponding precursors. Heating of 2 with p-nitrophenoxide afforded bis(p-nitrophenyl)ether 3, which was treated with hydrazine hydrate to give bis(p-aminophenyl)ether 4. Treatment of 4 with paraformaldehyde and triflouroacetic anhydride gave trögerophane 5. Reaction of 5 with trifluroacetic anhydride afforded phenhomazine derivative 6, which was treated with potassium carbonate to afford tetrahydrophenhomazine 7. Finally, reaction of 7 with phenacylchloride, bromoacetic acid, or ethyl bromoacetate in the presence of triethyl amine under reflux, afforded the corresponding macrocyclic compounds 8, 9 and 10, respectively. The synthesized trögerophane,precursors and its newly synthesized phenhomazines derivatives were screened for anticancer activity. Results revealed that 1,4,7,10-tetraoxa[10](2,8)trögerophane had a promising selectivity towards colon cancer cell line with an IC₅₀ of 92.7 µg/ml.

Synthesis, Docking, Computational Studies, and Antimicrobial Evaluations of New Dipeptide Derivatives Based on Nicotinoylglycylglycine Hydrazide

Within a series of dipeptide derivatives (5–11), compound 4 was refluxed with d-glucose, d-xylose, acetylacetone, diethylmalonate, carbon disulfide, ethyl cyanoacetate, and ethyl acetoacetate which yielded 5–11, respectively. The candidates 5–11 were characterized and their biological activities were evaluated where they showed different anti-microbial inhibitory activities based on the type of pathogenic microorganisms. Moreover, to understand modes of binding, molecular docking was used of Nicotinoylglycine derivatives with the active site of the penicillin-binding protein 3 (PBP3) and sterol 14-alpha demethylase’s (CYP51), and the results, which were achieved via covalent and non-covalent docking, were harmonized with the biological activity results. Therefore, it was extrapolated that compounds 4, 7, 8, 9, and 10 had good potential to inhibit sterol 14-alpha demethylase and penicillin-binding protein 3; consequently, these compounds are possibly suitable for the development of a novel antibacterial and antifungal therapeutic drug. In addition, in silico properties of absorption, distribution, metabolism, and excretion (ADME) indicated drug likeness with low to very low oral absorption in most compounds, and undefined blood–brain barrier permeability in all compounds. Furthermore, toxicity (TOPKAT) prediction showed probability values for all carcinogenicity models were medium to pretty low for all compounds.

Anticancer Activities of Newly Synthesized Chiral Macrocyclic Heptapeptide Candidates

As important cancer therapeutic agents, macrocyclic peptides have recently drawn great attention, mainly because they are synthetically accessible and have lower toxicity towards normal cells. In the present work, we synthesized newly macrocyclic pyridoheptapeptide derivatives. The synthesized derivatives were characterized using standard chemical and spectroscopic analytical techniques, and their anticancer activities against human breast and hepatocellular cancer cells were investigated. Results showed that compounds 1a and 1b were the most effective against hepatocellular (HepG2) and breast (MCF-7) cancer cell lines, respectively.

Chiral Pyridine-3,5-bis- (L-phenylalaninyl-L-leucinyl) Schiff Base Peptides as Potential Anticancer Agents: Design, Synthesis, and Molecular Docking Studies Targeting Lactate Dehydrogenase-A

A series of branched tetrapeptide Schiff bases 3–6 were designed and synthesized from corresponding tetrapeptide hydrazide 2 as a starting material.In vitroevaluation of the synthesized compounds 4–6 against breast MCF-7 carcinoma cells identified their excellent anticancer potency, with IC₅₀ ranging from 8.12 ± 0.14 to 17.55 ± 0.27 μM in comparison with the references, cisplatin and milaplatin (IC₅₀= 13.34 ± 0.11and 18.43 ± 0.13 μM, respectively). Furthermore, all derivatives demonstrated promising activity upon evaluation of theirin vitroandin vivosuppression of p53 ubiquitination and inhibition assessment for LDHA kinase. Finally, molecular docking studies were performed to predict the possible binding features of the potent derivatives within the ATP pocket of LDHA in an attempt to get a lead for developing a more potent LDHA inhibitor with anti-proliferative potency.

Synthesis of chiral 3,5-bis(l-phenylalaninyl-l-leucinyl)pyridine Schiff base and their macrocyclic carboxaimide derivatives using 3,5-bis(l-phenylalaninyl)-pyridine methyl ester

A series of linear tetrapeptides2–7and cyclooctapeptedopyridine derivatives8and9, were synthesized usingNα-dinicotinoyl-bis[(l-phenylalaninyl-l-leucyl)hydrazide]2as starting material. Acid hydrazide2was reacted with aromatic or heterocyclic aldehydes to give Schiff base derivatives3and4, respectively. Additionally, compound2was reacted with dicarboxylic acid anhydrides ortetracarboxylic diacid anhydrides to give the corresponding linear diimide carboxamides5–7, and octapeptide tetraimides8and9, respectively. The synthesized products were elucidated by using spectroscopic evidences and they were evaluated for their antibacterial activity by using streptomycin as reference antibiotic drug.

In silico Methods for Design of Kinase Inhibitors as Anticancer Drugs

Rational drug design implies usage of molecular modeling techniques such as pharmacophore modeling, molecular dynamics, virtual screening, and molecular docking to explain the activity of biomolecules, define molecular determinants for interaction with the drug target, and design more efficient drug candidates. Kinases play an essential role in cell function and therefore are extensively studied targets in drug design and discovery. Kinase inhibitors are clinically very important and widely used antineoplastic drugs. In this review, computational methods used in rational drug design of kinase inhibitors are discussed and compared, considering some representative case studies.

Cytotoxic and antimicrobial activities of some novel heterocycles employing 6-(1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile

A pyrimidinethione derivative namely, 6-(1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile, was readily synthesized and reacted with carbon electrophiles in an attempt to synthesize selected fused heterocycles. The reactivity of 6-(1,3-diphenyl-1H-pyrazol-4-yl)-4-oxo-2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carbonitrile was investigated towards selected nitrogen nucleophiles. Thiation and hydrolysis reactions of the tetrahydropyrimidine derivative were investigated. Antitumor and antimicrobial activity evaluation of some of the synthesized products exhibited promising results.

Antibacterial Evaluation, In Silico Characters and Molecular Docking of Schiff Bases Derived from 5-aminopyrazoles

A series of Schiff bases 14-25 were designed and synthesized for evaluation of their antibacterial properties against multi-drug resistant bacteria (MDRB). The antibacterial activities of Schiff bases 14-25 showed that most of the synthesized compounds displayed a significant antibacterial activity. Assessment of in silico ADMET properties (absorption, distribution, metabolism, excretion and toxicity) of Schiff bases illustrates that all derivatives showed agreement to the Lipinski's rule of five. Further enzymatic assay aided by molecular docking study demonstrated that compound 18 is a potent inhibitor of staphylococcus aureus DNA gyrase and dihydrofolate reductase kinases. This study could be valuable in the discovery of new potent antimicrobial agents.

In vitro anticancer potentiality and molecular modelling study of novel amino acid derivatives based on N1,N3-bis-(1-hydrazinyl-1-oxopropan-2-yl) isophthalamide

A series of N¹,N³-bis (1-oxopropan-2-yl) isophthalamide-based derivatives 4–16 were prepared and their structures were confirmed by different spectral tools. The cytotoxic potentiality of novel compounds 4–16 was assessed by the MTT assay method on colon, lung and breast tumour cell lines. Compound 5 gave the most significant specificity anticancer activity with safety response on normal cell lines. In vitro enzyme assay and several apoptotic parameters were examined to elucidate the mode of action of compound 5. Molecular docking studies also were simulated to put insight and give better understanding to its structural features.

Novel phthalimide based analogues: design, synthesis, biological evaluation, and molecular docking studies

Pyrazolylphthalimide derivative 4 was synthesized and reacted with different reagents to afford the target compounds imidazopyrazoles 5-7, pyrazolopyrimidines 9, 12, 14 and pyrazolotriazines 16, 17 containing phthalimide moiety. The prepared compounds were established by different spectral data and elemental analyses. Additionally, all synthesized derivatives were screened for their antibacterial activity against four types of Gram + ve and Gram-ve strains, and for antifungal activity against two fungi micro-organisms by well diffusion method. Moreover, the antiproliferative activity was tested for all compounds against human liver (HepG-2) cell line in comparison with the reference vinblastine. Moreover, drug-likeness and toxicity risk parameters of the newly synthesized compounds were calculated using in silico studies. The data from structure-actvity relationship (SAR) analysis suggested that phthalimide derivative bearing 3-aminopyrazolone moiety, 4 illustrated the best antimicrobial and antitumor activities and might be considered as a lead for further optimization. To investigate the mechanism of the antimicrobial and anticancer activities, enzymatic assay and molecular docking studies were carried out on E. coli topoisomerase II DNA gyrase B and VEGFR-2 enzymes.

Synthesis and investigation of 3,5-bis-linear and macrocyclic tripeptidopyridine candidates by using l-valine,N,N′-(3,5-pyridinediyldicarbonyl)bis-dimethyl ester as synthon

Interest in the synthesis of heterocyclic organic molecules with peptide moieties has gained attention due to their potential biological activities. The current work aimed at synthesizing new macrocyclic tripeptide imides and evaluating their possible antimicrobial activities. A series of 11 derivatives were prepared from dimethyl 3,5-pyridinevalinyl ester either by NaOH or NH2NH2treatment, followed by cyclization and further reaction with NaOH or NH2NH2. The majority of synthesized derivatives showed promising antibacterial and antifungal activities in comparison to standard known antibiotics. Compounds5aand7bshowed the most potential antibacterial againstStaphylococcus aureusand antifungal activities againstCandida albicans, respectively.

Cytotoxic Effects of Newly Synthesized Heterocyclic Candidates Containing Nicotinonitrile and Pyrazole Moieties on Hepatocellular and Cervical Carcinomas

In this study, a series of newly synthesized substituted pyridine 9, 11-18, naphthpyridine derivative 10 and substituted pyrazolopyridines 19-23 by using cycnopyridone 8 as a starting material. Some of the synthesized candidates are evaluated as anticancer agents against different cancer cell lines. In vitro cytotoxic activities against hepatocellular and cervical carcinoma cell lines were evaluated using standard MTT assay. Different synthesized compounds exhibited potential in vitro cytotoxic activities against both HepG2 and HeLa cell lines. Furthermore, compared to standard positive control drugs, compounds 13 and 19 showed the most potent cytotoxic effect with IC₅₀ values of 8.78 ± 0.7, 5.16 ± 0.4 μg/mL, and 15.32 ± 1.2 and 4.26 ± 0.3 μg/mL for HepG2 and HeLa cells, respectively.

Are peptides a solution for the treatment of hyperactivated JAK3 pathways?

While the inactivation mutations that eliminate JAK3 function lead to the immunological disorders such as severe combined immunodeficiency, activation mutations, causing constitutive JAK3 signaling, are known to trigger various types of cancer or are responsible for autoimmune diseases, such as rheumatoid arthritis, psoriasis, or inflammatory bowel diseases. Treatment of hyperactivated JAK3 is still an obstacle, due to different sensibility of mutation types to conventional drugs and unwanted side effects, because these drugs are not absolutely specific for JAK3, thus inhibiting other members of the JAK family, too. Lack of information, in which way sole inhibition of JAK3 is necessary for elimination of the disease, calls for the development of isoform-specific JAK3 inhibitors. Beside this strategy, up to date peptides are a rising alternative as chemo- or immunotherapeutics, but still sparsely represented in drug development and clinical trials. Beyond a possible direct inhibition function, crossing the cancer cell membrane and interfering in disease-causing pathways or triggering apoptosis, peptides could be used in future as adjunct remedies to potentialize traditional therapy and preserve non-affected cells. To discuss such feasible topics, this review deals with the knowledge about the structure-function of JAK3 and the actual state-of-the-art of isoform-specific inhibitor development, as well as the function of currently approved drugs or those currently being tested in clinical trials. Furthermore, several strategies for the application of peptide-based drugs for cancer therapy and the physicochemical and structural relations to peptide efficacy are discussed, and an overview of peptide sequences, which were qualified for clinical trials, is given.

Design, Synthesis, and Molecular Docking Study of Novel Heterocycles Incorporating 1,3,4-Thiadiazole Moiety as Potential Antimicrobial and Anticancer Agents

A new series of 5-(3,5-dinitrophenyl)-1,3,4-thiadiazole derivatives were prepared and evaluated for their in vitro antimicrobial, antitumor, and DHFR inhibition activity. Compounds 9, 10, 13, and 16 showed strong and broad-spectrum antimicrobial activity comparable to Amoxicillin and Fluconazole as positive antibiotic and antifungal controls, respectively. Compounds 6, 14, and 15 exhibited antitumor activity against four human cancer cell lines, CCRF-CEM leukemia, HCT-15 colon, PC-3 prostate, and UACC-257 melanoma cell lines using Doxorubicin as a reference drug. Compounds 10, 13, 14, and 15 proved to be the most active DHFR inhibitors with an IC₅₀ range of 0.04 ± 0.82–1.00 ± 0.85 µM, in comparison with Methotrexate (IC₅₀ = 0.14 ± 1.38 µM). The highly potent DHFR inhibitors shared a similar molecular docking mode and made a critical hydrogen bond and arene‒arene interactions via Ser59 and Phe31 amino acid residues, respectively.

Design, Synthesis, Anticancer Evaluation and Molecular Modeling of Novel Estrogen Derivatives

A series of estrone derivatives 3–8 was designed and synthesized using estrone arylmethylenes 2a,b as starting materials and their structures were confirmed by different spectral data and elemental analyses. All the newly synthesized compounds exhibited potent in vitro and in vivo cytotoxic activities against breast cancer cell lines. In addition, all compounds were subjected to in vitro and in vivo inhibition assays for EGFR and VEGFR-2 kinases as well as p53 ubiquitination activity to obtain more details about their mechanism of action. Based on the promising results, a molecular docking study was investigated for the most representative compound 5a against the two targets, EGFR and VEGFR-2 kinases, to assess its binding affinity, hoping to rationalize and obtain potent anticancer agents in the future.