Synthesis, anticonvulsant activity and 3D-QSAR study of some prop-2-eneamido and 1-acetyl-pyrazolin derivatives of aminobenzothiazole

Design of new Mcl-1 inhibitors for cancer using fragments hybridization, molecular docking, and molecular dynamics studies

Apoptosis is a critical process that regulates cell survival and death and plays an essential role in cancer development. The Bcl-2 protein family, including myeloid leukemia 1 (Mcl-1), is a key regulator of the intrinsic apoptosis pathway, and its overexpression in many human cancers has prompted efforts to develop Mcl-1 inhibitors as potential anticancer agents. In this study, we aimed to design new Mcl-1 inhibitors using various computational techniques. First, we used the Mcl-1 receptor-ligand complex to build an e-pharmacophore hypothesis and screened a library of 567,000 fragments from the Enamine database. We obtained 410 fragments and used them to design 92,384 novel compounds, which we then docked into the Mcl-1 binding cavity using HTVS, SP, and XP docking modes of Glide. To assess their suitability as drug candidates, we conducted MM-GBSA calculations and ADME prediction, leading to the identification of 10 compounds with excellent binding affinity and favorable pharmacokinetic properties. To further investigate the interaction strength, we performed molecular dynamics simulations on the top three Mcl-1 receptor-ligand complexes to study their interaction stability. Overall, our findings suggest that these compounds have promising potential as anticancer agents, pending further experimental validation such as Mcl-1 apoptosis Assay. By combining experimental methods with various in silico approaches, these techniques prove to be invaluable for identifying novel drug candidates with distinct therapeutic applications using fragment-based drug design. This methodology has the potential to expedite the drug discovery process while also reducing its costs.Communicated by Ramaswamy H. Sarma.

Catalytic response and molecular simulation studies in the development of synthetic routes in trimeric triaryl pyridinium type ionic liquids

Under conventional and silica-supported Muffle furnace methods, water-soluble substituted trimeric triaryl pyridinium cations with various inorganic counter anions are synthesized. The solvent-free synthesis method is superior to the conventional method in terms of non-toxicity, quicker reaction times, ease of workup, and higher yields. Trimeric substituted pyridinium salts acted as excellent catalytic responses for the preparation of Gem-bisamide derivatives compared with available literature. To evaluate the molecular docking, benzyl/4-nitrobenzyl substituted triaryl pyridinium salt compounds with VEGFR-2 kinase were used with H-bonds, π-π stacking, salt bridges, and hydrophobic contacts. The results showed that the VEGFR-2 kinase protein had the most potent inhibitory activity. Intriguingly, the compound [NBTAPy]PF₆^- had a strongly binds to VEGFR-2 kinase and controlled its activity in cancer treatment and prevention.

Abdallah M, M. Mukhtar R, Moutasim F, Rafie Ahmed A, Edris A, Ibraheem W, Makki AA, M. Elshamly E, Elhag R, Osman W, A. Mothana R, Alzain AA. Identification of Novel Natural Dual HDAC and Hsp90 Inhibitors for Metastatic TNBC Using e-Pharmacophore Modeling, Molecular Docking, and Molecular Dynamics Studies

Breast cancer (BC) is one of the main types of cancer that endangers women's lives. The characteristics of triple-negative breast cancer (TNBC) include a high rate of recurrence and the capacity for metastasis; therefore, new therapies are urgently needed to combat TNBC. Dual targeting HDAC6 and Hsp90 has shown good synergistic effects in treating metastatic TNBC. The goal of this study was to find potential HDAC6 and Hsp90 dual inhibitors. Therefore, several in silico approaches have been used. An e-pharmacophore model generation based on the HDAC6-ligand complex and subsequently a pharmacophore-based virtual screening on 270,450 natural compounds from the ZINC were performed, which resulted in 12,663 compounds that corresponded to the obtained pharmacophoric hypothesis. These compounds were docked into HDAC6 and Hsp90. This resulted in the identification of three compounds with good docking scores and favorable free binding energy against the two targets. The top three compounds, namely ZINC000096116556, ZINC000020761262, and ZINC000217668954, were further subjected to ADME prediction and molecular dynamic simulations, which showed promising results in terms of pharmacokinetic properties and stability. As a result, these three compounds can be considered potential HDAC6 and Hsp90 dual inhibitors and are recommended for experimental evaluation.

Turning down PI3K/AKT/mTOR signalling pathway by natural products: an in silico multi-target approach

The PI3K/AKT/mTOR pathway is a significant target for cancer drug discovery. Many efforts have focused on discovering new inhibitors against key kinase proteins involved in this pathway for cancer treatment. PI3K/mTOR dual inhibitors, such as PKI-179, have been reported to be more effective than agents that act only on a single protein target. The present computational study aimed to discover triple target inhibitors against PI3K, AKT, and mTOR proteins. Accordingly, the PI3K protein bound with the ligand was used as input for e-pharmacophore modelling to generate the pharmacophore hypothesis and then screened for a library of 270,540 natural products from the Zinc database resulting in 57,220 compounds that matched the hypothesis. These compounds were then docked into the active site of PI3K, resulting in 292 compounds with better docking scores than the co-crystallized ligand. These compounds were re-docked into AKT and mTOR proteins. Besides, MM-GBSA binding free energy calculations, MD simulations, and ADMET prediction were carried out, leading to 5 potential triple-target inhibitors namely, ZINC000014644152, ZINC000014760695, ZINC000014644839, ZINC000095099451, and ZINC000005998557. In conclusion, these inhibitors may be possible leads for inhibiting PI3K/AKT/mTOR pathway, and they may be further evaluated in vitro and clinically as anticancer agents.

De Novo Design of Cathepsin B1 Inhibitors as Potential Anti-Schistosomal Agents Using Computational Studies

Background

Schistosomiasis is the world’s second most devastating disease after malaria and the leading cause of disease and mortality for more than 200 million people in developing countries. Cysteine proteases, in particular SmCB1, are the most well-researched biological targets for this disorder.

Objective

To apply computational techniques to design new antischistosomal agents against SmCB1 protein with favorable pharmacokinetic properties.

Methods

The smCB1 receptor-based pharmacophore model was created and used to screen 567,000 fragments from the Enamine library. The best scoring fragments have been linked to build novel compounds that were subjected to molecular docking, MM-GBSA free energy estimation, ADME prediction, and molecular dynamics.

Results

A seven-point pharmacophore hypothesis ADDDRRR was created. The developed hypothesis was used to screen 1.3 M fragment conformations. Among them, 23,732 fragments matched the hypothesis and screened against the protein. The top 50 fragments were used to design new 7745 compounds using the Breed ligand panel which were subjected to docking and MMGBSA binding energy. This led to the identification of 10 compounds with better docking scores (−8.033– −7.483 kcal/mol) and lower-bound free energies (−58.49 – −40.02 kcal/mol) compared to the reference bound ligand. Most of the designed compounds demonstrated good drug-like properties. Concerning Molecular dynamics (MD) simulation results, a low root mean square deviation (RMSD) range (0.25–1.2 Å) was found for the top 3 complexes which indicated their stability.

Conclusion

We identified compounds that could be potential candidates in the search for novel Schistosoma mansoni inhibitors by targeting SmCB1 utilizing various computational tools. Three newly designed compounds namely breed 1, 2, and 3 showed promising affinity to the target as well as favorable drug-like properties which might be considered potential anti-schistosomal agents.

Discovery of novel natural products as rhodesain inhibitors for human African trypanosomiasis using in silico techniques

Human African Trypanosomiasis (HAT) or sleeping sickness is caused by the Trypanosoma brucei rhodesiense, a subspecies of the Trypanosomatide family. The parasite is associated with high morbidity and mortality rate in both animals and humans, claimed to be more fatal than other vector-transmitted diseases such as malaria. The majority of existing medications are highly toxic, not effective in the late chronic phase of the disease, and require maximum dosages to fully eradicate the parasite. In this study, we used computational methods to find out natural products that inhibit the Rhodesain, a parasitic enzyme that plays an important role in the parasite's pathogenicity, multiplication, and ability to pass through the host's blood-brain barrier. A library of 270540 natural products from ZINC databases was processed by using e-pharmacophore hypnosis and screening procedures, molecular docking, ADMET processes, and MM-GBSA calculations. This led to the identification of 3 compounds (ZINC000096269390, ZINC000035485292, and ZINC000035485242) which were then subjected to molecular dynamics. The findings of this study showed excellent binding affinity and stability toward the Rhodesain and suggest they may be a hopeful treatment for HAT in the future if further clinical trials were performed.Communicated by Ramaswamy H. Sarma.

N-Acylated and N-Alkylated 2-Aminobenzothiazoles Are Novel Agents That Suppress the Generation of Prostaglandin E2

The quest for novel agents to regulate the generation of prostaglandin E₂ (PGE₂) is of high importance because this eicosanoid is a key player in inflammatory diseases. We synthesized a series of N-acylated and N-alkylated 2-aminobenzothiazoles and related heterocycles (benzoxazoles and benzimidazoles) and evaluated their ability to suppress the cytokine-stimulated generation of PGE₂ in rat mesangial cells. 2-Aminobenzothiazoles, either acylated by the 3-(naphthalen-2-yl)propanoyl moiety (GK510) or N-alkylated by a chain carrying a naphthalene (GK543) or a phenyl moiety (GK562) at a distance of three carbon atoms, stand out in inhibiting PGE₂ generation, with EC₅₀ values ranging from 118 nM to 177 nM. Both GK510 and GK543 exhibit in vivo anti-inflammatory activity greater than that of indomethacin. Thus, N-acylated or N-alkylated 2-aminobenzothiazoles are novel leads for the regulation of PGE₂ formation.

Identification of novel TMPRSS2 inhibitors for COVID-19 using e-pharmacophore modelling, molecular docking, molecular dynamics and quantum mechanics studies

SARS coronavirus 2 (SARS-CoV-2) has spread rapidly around the world and continues to have a massive global health effect, contributing to an infectious respiratory illness called coronavirus infection-19 (COVID-19). TMPRSS2 is an emerging molecular target that plays a role in the early stages of SARS-CoV-2 infection; hence, inhibiting its activity might be a target for COVID-19. This study aims to use many computational approaches to provide compounds that could be optimized into clinical candidates. As there is no experimentally derived protein information, initially we develop the TMPRSS2 model. Then, we generate a pharmacophore model from TMPRSS2 active site consequently, and the developed models were employed for the screening of one million molecules from the Enamine database. The created model was then screened using e-pharmacophore-based screening, molecular docking, free energy estimation and molecular dynamic simulation. Also, ADMET prediction and density functional theory calculations were performed. Three potential molecules (Z126202570, Z46489368, and Z422255982) exhibited promising stable binding interactions with the target. In conclusion, these findings empower further in vitro and clinical assessment for these compounds as novel anti-COVID19 agents.

Recent Development in Substituted Benzothiazole as an Anticonvulsant Agent

Heterocyclic compounds and their derivatives gained more attention due to their valuable biological and pharmacological properties. Benzothiazole is a heterocyclic structure containing a bicyclic ring system with a large panel of applications. The benzothiazole is present in many new products undergoing research hoping that it possesses various biological activities. Epilepsy is a diverse group of diseases marked by neuronal excitability and hypersynchronous neuronal activity of motor, sensory or autonomic events with or without loss of consciousness. Presently, many antiepileptic drugs like lamotrigine, stiripentol tiagabine, pregabalin, felbamate, and topiramate are available and effective towards 60-80% of patients only, along with undesirable side effects, such as hepatotoxicity, gastrointestinal disturbance, drowsiness, gingival hyperplasia, and hirsutism. Thus, many attempts are still on-going to develop antiepileptic drugs with a safer profile. This review is mainly focused on the compilation of reported scientific literature data in the recent one-decade on the anticonvulsant activity of benzothiazole compounds.

Synthesis and Anticancer Activity of Thiadiazole Containing Thiourea, Benzothiazole and Imidazo[2,1-b][1,3,4]thiadiazole Scaffolds

BACKGROUND

A great array of nitrogen-containing heterocyclic rings were being extensively explored for their functional versatility in the field of medicine, especially in anticancer research. 1,3,4- thiadiazole is one of such heterocyclic rings with promising anticancer activity against several cancer cell lines, inhibiting diverse biological targets.

INTRODUCTION

The 1,3,4-thiadiazole, when equipped with other heterocyclic scaffolds, has displayed enhanced anticancer properties. The thiourea, benzothiazole, imidazo[2,1,b][1,3,4]-thiadiazoles are such potential scaffolds with promising anticancer activity.

METHODS

A new series of 5-substituted-1,3,4-thiadiazoles linked with phenyl thiourea, benzothiazole and 2,6-disubstituted imidazo[2,1-b][1,3,4]thiadiazole derivatives were synthesized and tested for invitro anticancer activity on various cancer cell lines.

RESULTS

The National Cancer Institute's preliminary anticancer screening results showed compounds 4b and 5b having potent antileukemic activity. Compound 4b selectively showed 32 percent lethality on Human Leukemia-60 cell line. The docking studies of the derivatives on aromatase enzyme (Protein Data Bank: 3S7S) have shown reversible interactions at the active site with good docking scores comparable to Letrozole and Exemestane. Furthermore, the selected derivatives were tested for anticancer activity on HeLa cell line based on the molecular docking studies.

CONCLUSION

Compounds 4b and 5b showed effective inhibition equivalent to Letrozole. These preliminary biological screening studies have given positive anticancer activity for these new classes of derivatives. An additional research study like the mechanism of action of the anticancer activity of this new class of compounds is necessary. These groundwork studies illuminate a future pathway for research of this class of compounds enabling the discovery of potent antitumor agents.

Cloud 3D-QSAR: a web tool for the development of quantitative structure-activity relationship models in drug discovery

Effective drug discovery contributes to the treatment of numerous diseases but is limited by high costs and long cycles. The Quantitative Structure-Activity Relationship (QSAR) method was introduced to evaluate the activity of a large number of compounds virtually, reducing the time and labor costs required for chemical synthesis and experimental determination. Hence, this method increases the efficiency of drug discovery. To meet the needs of researchers to utilize this technology, numerous QSAR-related web servers, such as Web-4D-QSAR and DPubChem, have been developed in recent years. However, none of the servers mentioned above can perform a complete QSAR modeling and supply activity prediction functions. We introduce Cloud 3D-QSAR by integrating the functions of molecular structure generation, alignment, molecular interaction field (MIF) computing and results analysis to provide a one-stop solution. We rigidly validated this server, and the activity prediction correlation was R2 = 0.934 in 834 test molecules. The sensitivity, specificity and accuracy were 86.9%, 94.5% and 91.5%, respectively, with AUC = 0.981, AUCPR = 0.971. The Cloud 3D-QSAR server may facilitate the development of good QSAR models in drug discovery. Our server is free and now available at http://chemyang.ccnu.edu.cn/ccb/server/cloud3dQSAR/ and http://agroda.gzu.edu.cn:9999/ccb/server/cloud3dQSAR/.

Importance of Fluorine in Benzazole Compounds

Fluorine-containing heterocycles continue to receive considerable attention due to their unique properties. In medicinal chemistry, the incorporation of fluorine in small molecules imparts a significant enhancement their biological activities compared to non-fluorinated molecules. In this short review, we will highlight the importance of incorporating fluorine as a basic appendage in benzothiazole and benzimidazole skeletons. The chemistry and pharmacological activities of heterocycles containing fluorine during the past years are compiled and discussed.

Recent advancement in the discovery and development of anti-epileptic biomolecules: An insight into structure activity relationship and Docking

Although there have been many advancements in scientific research and development, the cause of epilepsy still remains an open challenge. In spite of high throughput research in the field of anti-epileptic drugs, efficacy void is still prevalent before the researchers. Researchers have persistently been exploring all the possibilities to curb undesirable side effects of the anti-epileptic drugs or looking for a more substantial approach to diminish or cure epilepsy. The drug development has shown a hope to medicinal chemists and researchers to carry further research by going through a substantial literature survey. This review article attempts to describe the recent developments in the anti-epileptic agents, pertaining to different molecular scaffolds considering their structure-activity relationship, docking studies and their mechanism of actions.

Synthesis, Biological Evaluation and Molecular Docking Study of Pyrazole, Pyrazoline Clubbed Pyridine as Potential Antimicrobial Agents

Introduction:

In continuation of our efforts to find new antimicrobials, herein we report the synthesis of various pyrazole, pyrazoline, and pyridine based novel bioactive heterocycles (3a-t).

Methods:

Newly synthesized compounds were analysed for their antimicrobial activity. Compounds 3c, 3h, 3i, 3k, 3n, and 3q showed significant antimicrobial activity.

Results:

Molecular docking study for the most active analogues against DNA gyrase subunit b (PDB ID: 1KZN) corroborated well with the observed antimicrobial potency exhibiting significant binding affinity.

Conclusion:

Interpretation of the chemical structures reported in this paper was based on IR, 1H NMR, 13C NMR, and mass spectral data.

Identification of benzimidazole containing 4H-chromen-4-one derivative as potential MAP kinase inhibitors by in-silico approaches

MAP kinase is one of the important targets in the treatment of osteoarthritis, inflammation and cancer. Many p38 inhibitors with diverse chemical structures and modes of protein interaction have been designed on the basis of their ability to compete with ATP site or allosteric site for binding to MAP Kinase. This study involves the molecular docking of benzimidazoles containing 4H-chrome-4-one derivatives as potent inhibitors of the MAP kinase enzyme. The compounds were computationally designed and optimized with the molecular docking to investigate the interactions between the target compounds and the amino acid residues of the MAP Kinase. The inhibitory activities against human MAP kinase enzyme were investigated by molecular docking using the Autodock and discovery studio software. All the designed compounds were shown good binding energy when compared with the binging energies of standard drug Imatinib (anti-cancer). Among all the designed compounds, compound D1 and D6 have higher binding energy values when compared to standard drug. Here we also studied the molecular properties of designed compound using Molinspiration software. Further, we planned to synthesis these benzimidazole derivatives and screen for in-vitro and in-vivo of anti-cancer activity.

Pyrazoline Hybrids as Promising Anticancer Agents: An Up-to-Date Overview

Pyrazolines are five-membered heterocycles possessing two adjacent nitrogens. They have attracted significant attention from organic and medicinal chemists due to their potent biological activities and the numerous possibilities for structural diversification. In the last decade, they have been intensively studied as targets for potential anticancer therapeutics, producing a steady yearly rise in the number of published research articles. Many pyrazoline derivatives have shown remarkable cytotoxic activities in the form of heterocyclic or non-heterocyclic based hybrids, such as with coumarins, triazoles, and steroids. The enormous amount of related literature in the last 5 years prompted us to collect all these published data from screening against cancer cell lines, or protein targets like EGFR and structure activity relationship studies. Therefore, in the present review, a comprehensive account of the compounds containing the pyrazoline nucleus will be provided. The chemical groups and the structural modifications responsible for the activity will be highlighted. Moreover, emphasis will be given on recent examples from the literature and on the work of research groups that have played a key role in the development of this field.

From Riluzole to Dexpramipexole via Substituted-Benzothiazole Derivatives for Amyotrophic Lateral Sclerosis Disease Treatment: Case Studies

The 1,3-benzothiazole (BTZ) ring may offer a valid option for scaffold-hopping from indole derivatives. Several BTZs have clinically relevant roles, mainly as CNS medicines and diagnostic agents, with riluzole being one of the most famous examples. Riluzole is currently the only approved drug to treat amyotrophic lateral sclerosis (ALS) but its efficacy is marginal. Several clinical studies have demonstrated only limited improvements in survival, without benefits to motor function in patients with ALS. Despite significant clinical trial efforts to understand the genetic, epigenetic, and molecular pathways linked to ALS pathophysiology, therapeutic translation has remained disappointingly slow, probably due to the complexity and the heterogeneity of this disease. Many other drugs to tackle ALS have been tested for 20 years without any success. Dexpramipexole is a BTZ structural analog of riluzole and was a great hope for the treatment of ALS. In this review, as an interesting case study in the development of a new medicine to treat ALS, we present the strategy of the development of dexpramipexole, which was one of the most promising drugs against ALS.

Synthetic and therapeutic perspectives of nitrogen containing heterocycles as anti-convulsants

Epilepsy is one of the commonly prevailing neurological disorders. According to the reports, it is evident that about 80% of the epileptic cases have been observed in developing countries. Although there are many drugs with significant potency available in the market; still there is an issue of selectivity and toxicity. Therefore, continuous attempts have been made by the researchers to develop newer therapeutic agents against epilepsy. Many synthetic strategies have been available in the literature to synthesize various classes of anticonvulsants with promising activity. In the presented review, authors have summarized some newer synthetic routes being used for the synthesis of nitrogen-containing anticonvulsants taking a cue from the reported established anticonvulsant drugs viz. vigabatrin, sodium valproate, oxcarbazepine, felbamate, retigabine, and gabapentin. Various derivatives with the substitution for better anticonvulsant profile have been described in the figures for easy comparative study. The structure-activity relationship (SAR) of compounds with maximum potency has also been discussed. This article may serve as a boost for the researchers to modify the pre-existing synthetic routes as well as to improve potency and yield of the compounds.

Synthesis, Type II diabetes inhibitory activity, antimicrobial evaluation and docking studies of indeno[1,2-c]pyrazol-4(1H)-ones

We report a convenient and efficient synthesis of indeno[1,2-c]pyrazol-4(1H)-ones (4a‒o) by the reaction of a variety of 2-acyl-(1H)-indene-1,3(2H)-diones (1) and 2-hydrazinylbenzo[d]thiazole/2-hydrazinyl-6-substitutedbenzo[d]thiazoles (2) in the presence of glacial acetic acid in good yields. The structure of the compounds thus prepared were confirmed by analytical and spectral (FT-IR, ¹H NMR, ¹³C NMR, and HRMS) techniques. All the synthesized indeno[1,2-c]pyrazol-4(1H)-ones (4a‒o) were assayed for their in vitro Type II diabetes inhibitory activity by using Acarbose as standard drug and in vitro antimicrobial activity utilizing Streptomycin and Fluconazole as reference drugs. Among the synthesized derivatives, 4e (IC₅₀ = 6.71 μg/mL) was found to be more potent against α-glucosidase enzyme as compared with the standard Acarbose (IC₅₀ = 9.35 μg/mL) and 4i (IC₅₀ = 11.90 μg/mL) exhibited good inhibitory activity against α-amylase enzyme as compared with the standard Acarbose (IC₅₀ = 22.87 μg/mL). Also, all the titled compounds showed good antimicrobial activity. In addition, in vitro α-glucosidase and α-amylase inhibition were supported by docking studies performed on the derivatives 4e and 4o, respectively.

Structural Activity Relationship and Importance of Benzothiazole Derivatives in Medicinal Chemistry: A Comprehensive Review

:

Benzothiazole (1, 3-benzothiazole) is one of the heterocyclic compounds, which is a weak base having varied biological activities. The unique methine center present in the thiazole ring makes benzothiazole as the most important heterocyclic compound. It is a common and integral structure of many natural and synthetic bioactive molecules. Benzothiazole derivatives show a variety of activities, with less toxic effects and their derivatives showed enhanced activities, which has proven Benzothiazole scaffold as one of the important moieties in medicinal chemistry. Benzothiazole ring containing compounds possess various pharmacological activities such as anti-viral, anti-microbial, antiallergic, anti-diabetic, anti-tumor, anti-inflammatory, anthelmitic and anti-cancer, which makes benzothiazole a rapidly developing and interesting compound in the medicinal chemistry. This review briefly explains the importance, common methods of synthesis of the benzothiazole scaffold and also explains the popular benzothiazole molecules which have applications in various fields of chemistry. A review has been carried out based on various pharmacological activities containing benzothiazole moieties and rationalize the activities based on the structural variations. Literature on benzothiazole derivatives reveals that substitution on the C-2 carbon atom and C-6 are the reasons for a variety of biological activities.

Some 1,3,5-trisubstituted pyrazoline derivatives targeting breast cancer: Design, synthesis, cytotoxic activity, EGFR inhibition and molecular docking

Different 1,3,5-trisubstituted pyrazoline derivatives 2a-c, 3-c, 4a-f, 6a-c, 7a-f and 8a-d were prepared via condensation reaction of the appropriate chalcone 1a-c or 5a-c with various hydrazine derivatives. All compounds were screened for their cytotoxicity against breast MCF-7 cancer cell line and the normal fibroblasts WI-38. Thirteen compounds 2a, 3a, 3c, 4a-d, 6c, 7d, 7e, 8b, 8d and 8f revealed promising cytotoxicity against MCF-7 compared to the reference standard staurosporine and they were safe to the normal fibroblasts WI-38. In addition, compounds 3c, 6c, 7d, 8b and 8d elicited higher cytotoxicity than erlotinib and exhibited promising EGFR inhibitory activity at submicromolar level comparable to that of erlotinib except for compound 8b that may exert its cytotoxicity via another mechanism besides EGFR inhibition. Molecular docking of 3c, 6c, 7d, 8b and 8d in the active site of EGFR confirmed the obtained results.

Pharmacophore modeling and 3D-QSAR studies of 2,4-disubstituted pyrimidine derivatives as Janus kinase 3 inhibitors

A robust pharmacophore model was developed and the structure-activity relationship was analyzed using 71 pyrimidine derivatives reported for covalent Janus Kinase 3 (JAK3) inhibition. Pharmacophore modeling developed a five featured pharmacophore: one H-bond acceptor, two H-bond donors, one hydrophobic, and one aromatic ring features. The atom-based three-dimensional QSAR models with statistical significance were generated using the training set of 52 compounds. The excellent predictive correlation coefficients were obtained for 3D models determined using a test set of 19 molecules. The generated QSAR model implies that the hydrophobic character is important for the JAK3 inhibitory activity of these compounds. Additionally, electron-withdrawing and hydrogen bond donor groups at specific positions positively contribute to the JAK3 inhibition potency. These results provided essential three-dimensional structural requirements and the crucial binding features of 2,4-disubstituted pyrimidine derivatives, which may direct for the design and discovery of novel potent JAK3 inhibitors.

A Review on Anticancer Potentials of Benzothiazole Derivatives

Benzothiazole is an organic compound bearing a heterocyclic nucleus (thiazole) which imparts a broad spectrum of biological activities to it. The significant and potent activity of benzothiazole moiety influenced distinctively by nature and position of substitutions. This review summarizes the effect of various substituents in recent trends and approaches to design and develop novel benzothiazole derivatives for anticancer potential in different cell lines by interpreting the Structure- Activity Relationship (SAR) and mechanism of action of a wide range of derivatives. The list of derivatives is categorized into different groups and reviewed for their anticancer activity. The structure-activity relationship for the various derivatives revealed an excellent understanding of benzothiazole moiety in the field of cancer therapy against different cancer cell line. Data obtained from the various articles showed the potential effect of benzothiazole moiety and its derivatives to produce the peculiar and significant lead compound. The important anticancer mechanisms found are tyrosine kinase inhibition, topoisomerase inhibition and induction of apoptosis by Reactive Oxygen Species (ROS) activation. Therefore, the design and development of novel benzothiazole have broad scope in cancer chemotherapy.

Sulfonic Acid-Functionalized Magnetic Nanoparticles as an Efficient Catalyst for the Synthesis of Benzo[4, 5]imidazo[1, 2-a]pyrimidine Derivatives, 2-Aminobenzothia Zolomethylnaphthols and 1-Amidoalkyl-2-naphthols

BACKGROUND

Carbon-based sulfonated catalysts have several advantages but their separation by filtration is still a challenge. On the other hand, the synthesis of magnetic sulfonated carbon nanoparticle indicated that the magnetic separation could be an efficient way to separate the catalyst from the reaction mixture.

OBJECTIVE

In order to synthesize a separable magnetic Fe3O4@C-SO3H nanoparticle (MNPs) with high catalytic activity in organic transformation, three environmental-benign and low-cost sulfonic acidfunctionalized magnetic nanoparticle (Fe3O4@C-SO3H) were successfully synthesized.

MATERIALS AND METHODS

The Nano catalysts were prepared by solvothermal carbonization of Sucrose (Suc), Starch (Sta) or Cellulose (Cel) in the presence of Fe3O4 Nanoparticle and then grafting of the sulfonic groups on the surface of resulted Fe3O4@C nanoparticles in the presence of p-Toluenesulfonic. Then the Nano catalysts were characterized using XRD, FESEM and FT-IR.

RESULTS

Three Fe3O4@C-SO3H were successfully synthesized. The resulted MNPs were used for the synthesis of benzo [4, 5] imidazo[1, 2-a]-pyrimidine derivatives, 2/-aminobenzothiazolomethylnaphthols and 1-amidoalkyl-2-naphthols under solvent-free conditions in excellent yields. It was found that high catalytic activity and easy magnetic separation from the reaction mixture are important achievement with regard to the efficiency and reusability of the catalyst in synthesis.

CONCLUSION

The MNPs were synthesized and used as an efficient catalysts for the one-pot synthesis of benzo [4, 5] imidazo[1, 2-a]-pyrimidine derivatives, 2/-aminobenzothiazolomethylnaphthols, and 1-amidoalkyl-2- naphthols under solvent-free conditions in excellent yields. High catalytic activity and easy magnetic separation from the reaction mixture are two factors for evaluating the performance of Fe3O4@C-SO3H nanoparticles in the organic transformations.

Enaminone-Derived Pyrazoles with Antimicrobial Activity

A series of pyrazoles derived from the substituted enaminones were synthesized and were evaluated for antimicrobial activity. All the compounds were characterized by the spectral data and elemental analysis. The synthesized compounds were initially screened for their antimicrobial activity against ATCC 6538, NCTC 10400, NCTC 10418, and ATCC 27853. During initial screening, compounds (P1, P6, and P11) presented significant antimicrobial activity through disc diffusion assay. These compounds were further evaluated for antimicrobial activity at different time points against Gram-positive and Gram-negative bacteria and presented significant activity for 6 hours. The activity was found to be greater against Gram-positive bacteria. In contrast at 24 hours, the activity was found only against Gram-positive bacteria except compound (P11), showing activity against both types of bacteria. Compound (P11) was found to have highest activity against both Gram-positive and Gram-negative bacteria.

Molecular docking, QSAR properties and DNA/BSA binding, anti-proliferative studies of 6-methoxy benzothiozole imine base and its metal complexes

The molecular and QSAR (Quantitative Structure-Activity Relationship) properties of title compound 2-((6-Methoxybenzo[d]thiazol-2-ylimino)methyl)-6-ethoxyphenol (HL) were evaluated employing HyperChem 7.5 tools. The interaction of the 1a-1e complexes of HL with calf thymus DNA (CT-DNA) was investigated by absorption titrations, Fluorescence quenching and viscosity measurements. The experimental data suggest that these complexes bind to CT-DNA through an intercalative mode, wherein DNA-binding affinity of 1e is found to be greater compared to other complexes. The tryptophan emission-quenching with bovine serum albumin (BSA) experiment revealed stronger binding of 1e than other complexes in the hydrophobic region of protein. The photocleavage of plasmid pBR322 DNA investigated in the presence of the title complexes inferred conversion of supercoiled form of DNA plasmid to circular nicked form. Free-radical scavenging activity studies of HL and its metal complexes determined by their interaction with the stable free-radical DPPH have shown promising antioxidant property. Further cytotoxicity studies with HeLa and MCF-7 cell lines indicated that the compounds can efficiently inhibit the cell proliferation in a dose dependent manner. The DAPI staining assay studies revealed the higher potency of 1e to induce apoptosis. AbbreviationsBSABovine serum albumin proteinCT-DNACalf thymus DNADMSODimethyl sulfoxideDAPI4',-6-Diamidino-2-phenylindole dihydrochlorideESI-MSElectrospray ionization mass spectrometryIC₅₀Half-maximal inhibitory concentrationMBTYE2-((6-methoxybenzo[d]thiazol-2-ylimino) methyl)-6-ethoxyphenolMTT3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromidePBSPhosphate-buffered salineTrisTris(hydroxymethyl)aminomethaneCommunicated by Ramaswamy H. Sarma.

Synthesis, characterization, molecular docking and biological activities of novel pyrazoline derivatives

In this study, synthesis of ethyl 2-((4-bromophenyl)diazenyl)-3-oxo-phenylpropanoate 1 was carried out and a series of new 3H-pyrazol-3-ones (P1-7) were synthesized from 1 as well as various hydrazines. The obtained yields of the synthesized compounds were moderate (40-70%) and these compounds were confirmed by spectral data. These novel pyrazoline derivatives were effective inhibitor compounds of the human carbonic anhydrase I and II isozymes (hCAs I and II) and of the acetylcholinesterase (AChE) enzyme, with K_i values in the range of 17.4-40.7 nM for hCA I, 16.1-55.2 nM for hCA II, and 48.2-84.1 nM for AChE. In silico studies were performed on the compounds inhibiting hCA I, hCA II, and AChE receptors. On the basis of the findings, the inhibition profile of the new pyrazoline compounds at the receptors was determined.