New chalcones bearing isatin scaffold: synthesis, molecular modeling and biological evaluation as anticancer agents

Chalcone: A Promising Bioactive Scaffold in Medicinal Chemistry

Chalcones are a class of privileged scaffolds with high medicinal significance due to the presence of an α,β-unsaturated ketone functionality. Numerous functional modifications of chalcones have been reported, along with their pharmacological behavior. The present review aims to summarize the structures from natural sources, synthesis methods, biological characteristics against infectious and non-infectious diseases, and uses of chalcones over the past decade, and their structure–activity relationship studies are detailed in depth. This critical review provides guidelines for the future design and synthesis of various chalcones. In addition, this could be highly supportive for medicinal chemists to develop more promising candidates for various infectious and non-infectious diseases.

Therapeutic Outcomes of Isatin and Its Derivatives against Multiple Diseases: Recent Developments in Drug Discovery

Isatin (1H indole 2, 3-dione) is a heterocyclic, endogenous lead molecule recognized in humans and different plants. The isatin nucleus and its derivatives are owed the attention of researchers due to their diverse pharmacological activities such as anticancer, anti-TB, antifungal, antimicrobial, antioxidant, anti-inflammatory, anticonvulsant, anti-HIV, and so on. Many research chemists take advantage of the gentle structure of isatins, such as NH at position 1 and carbonyl functions at positions 2 and 3, for designing biologically active analogues via different approaches. Literature surveys based on reported preclinical, clinical, and patented details confirm the multitarget profile of isatin analogues and thus their importance in the field of medicinal chemistry as a potent chemotherapeutic agent. This review represents the recent development of isatin analogues possessing potential pharmacological action in the years 2016–2020. The structure–activity relationship is also discussed to provide a pharmacophoric pattern that may contribute in the future to the design and synthesis of potent and less toxic therapeutics.

Upregulation of BAX and caspase-3, as well as downregulation of Bcl-2 during treatment with indeno[1,2-b]quinoxalin derivatives, mediated apoptosis in human cancer cells

Cancer is the world's foremost cause of death. There are over 100 different forms of cancer. Cancers are frequently named after the organs or tissues in which they develop. As a part of our aim to develop promising anticancer agents, a series of new indeno[1,2-b]quinoxaline derivatives were synthesized. All of the synthesized compounds were tested for anticancer activity in vitro in three human cancer cell lines: the HCT-116 colon cancer cell line, the HepG-2 liver cancer cell line, and the MCF-7 breast cancer cell line. Among the tested derivatives, 2, 3, 5, 12, 21, and 22 showed exceptional antiproliferative activities against the three tested cell lines compared to the reference standard imatinib. These compounds were, therefore, selected for further investigations. Evaluation of their cytotoxicity against a normal human cell line (WI-38) was performed, to ensure their safety and selectivity (IC₅₀  > 92 μM). Then, induction of apoptosis by the most active compounds was found to be accomplished by downregulation of Bcl-2 and upregulation of BAX and caspase-3. After that, the most promising apoptotic compound that increases the caspase-3 and BAX expression and downregulates Bcl-2 activity (3) was assessed for its impact on the cell cycle distribution in HepG-2 cells: The most potent derivative (3) induced cell cycle arrest at the G2/M phase. Finally, in silico evaluation of the ADME properties indicated that compound 3 is orally bioavailable and can be readily synthesized on a large scale.

In vivo screening and toxicity studies of indolinone incorporated thiosemicarbazone, thiazole and piperidinosulfonyl moieties as anticonvulsant agents

Based on the biological importance of the thiazole nucleus, we decided to prepare and evaluate the biological activity of some new isatin derivatives containing thiazole moiety. The 5-(piperidin-1-ylsulfonyl)indoline-2,3-dione (1) was prepared and used as a starting material in the synthesis of many isatin derivatives for anticonvulsant evaluation. All the newly synthesized thiazlidino/thiosemicarbazide-indolin-2-one derivatives screened in vivo for their anticonvulsant activity against pentylenetetrazole-induced convulsions in mice. The results were compared with phenobarbitone sodium as a standard anticonvulsant drug. Most of the tested compounds exhibited anticonvulsant activity with relative potency ranging from 0.02 to 0.2 in comparison to standard drug phenobarbitone. The most active compounds 3, 6a, 6c and 8, were exposed to further investigations in rats to evaluate the effect of most active derivatives on the haematological, liver, kidney functions as well as histopathological studies of the liver and kidney tissues. Finally, the most potent compounds 3, 6a, 6c and 8 observed good toxic properties for both liver and kidney function with mild variability changes on RBCs, WBCs, Platelets, Hb, AST, ALT, and creatinine level, as well as kidney and liver tissue and these good results obtained rather than used low dose from phenobarbitone.

In vitro Evaluation of Isatin derivatives as Potent Anti-Breast Cancer Agents against MCF-7, MDA MB 231, MDA-MB 435 and MDA-MB 468 Breast Cancers cell lines: A Review

INTRODUCTION

Breast cancer (BC) is one of the most frequent malignancy and most common reasons of impermanence in women. The backbone of therapy for BC is principally chemotherapy, but due to its non-specific nature between normal cells and cancer cells and severe side effects are the main barriers in its therapy. So, there is an intense requirement for the enlargement of more efficacious, more specific and safer anti-BC agents.

OBJECTIVE

Isatin (IST) is an endogenous molecule which is a principal class of heterocyclic compounds and exhibits a wide range of therapeutic activities which can be used as a starting material for the synthesis of several drug molecules. Many literatures were reported previously on different pharmacological activities of IST derivatives and particularly on anticancer activity but this review mainly focus on anti-BC activities of IST derivatives through MCF-7, MDA MB 231, MDA-MB 435 and MDA-MB 468 cell lines. Here in we mentioned, a total 33 IST derivatives (compound 24- 56) which shown good anti-BC activity. IST derived compounds are also available in market and are used for various cancer types like sunitinib for renal cell carcinoma (RCC) and Nintedanib used for the cryptogenic fibrosing alveolitis treatment but when evaluated for BC did not get much success.

CONCLUSION

This review mainly highlights anti-BC activities of various IST analogues using MCF-7, MDA MB 231, MDA-MB 435 and MDA-MB 468 cell lines, display the potent compound of the series and structure-activity relationships of compounds with molecular docking also. So, this study mainly shows the importance of IST as major sources for drug design and development of newer anti-BC drugs.

In vitro antimicrobial evaluation and in silico studies of coumarin derivatives tagged with pyrano-pyridine and pyrano-pyrimidine moieties as DNA gyrase inhibitors

Several coumarin-containing substitute nitrogen heterocycles have recently received considerable importance due to their diverse pharmacological properties. One-pot and rapid synthesis of coumarin derivatives was achieved via reactions of acetyl-coumarin with p-chloro-benzaldehyde and malononitrile to provide compound 2-containing cyano-amine using conventional heating. Compound 2 was condensed with different carbon electrophiles triethyl orthoformate, phenyl isocyanate, carbon disulfide, benzoyl chloride, and acetyl chloride that afforded the corresponding chromene derivatives 3-17. All the newly synthesized compounds were characterized by elemental and spectroscopic evidences. All of the synthesized compounds were tested for antimicrobial activity against S. Pneumoniae, S. Epidermidis, S. Aureus, and E. coli as Gram + ve Bacteria, K. Pneumoniae, S. Paratyphi as Gram -ve Bacteria, P. Italicum, A. Fumigatus representative for Fungi. The preliminary screening results showed that most of the compounds had moderate to high activity against all tested organisms. The most potent four compounds were subjected to further investigation against E. Coli DNA gyrase and topoisomerase IV inhibitory activity, and the results showed that all of these derivatives inhibit DNA gyrase and thus cell division. Also, in silico studies were done for the most active compounds which showed good results.

Isatin-derived azoles as new potential antimicrobial agents: Design, synthesis and biological evaluation

Novel antibiotics are forced to be developed on account of multidrug-resistant bacteria with serious threats to human health. This work developed isatin-derived azoles as new potential antimicrobial agents. Bioactive assay revealed that isatin hybridized 1,2,4-triazole 7a exhibited excellent inhibitory activity against E. coli ATCC 25,922 with an MIC value of 1 µg/mL, which was 8-fold more potent than reference drug norfloxacin. The active molecule 7a possessed the ability to kill some bacteria and fungi as well as displayed low propensity to induce resistance towards E. coli ATCC25922. Preliminary mechanism investigation indicated that hybrid 7a might block deoxyribonucleic acid (DNA) replication by intercalating with DNA and possibly interacting with DNA polymerase III, thus exerting its antimicrobial potency.

Development of adamantane scaffold containing 1,3,4-thiadiazole derivatives: Design, synthesis, anti-proliferative activity and molecular docking study targeting EGFR

A new series of 1,3,4-thiadiazolo-adamantane derivatives were synthesized through molecular hybridization approach, then used as starting material to synthesize chloro and cyano acetamide-thiadiazole derivatives 2, 3. The newly designed compounds 1-3 were treated with different reagents to design 5-adamantyl thiadiazole derivatives 4-17 and evaluate their in vitro anti-proliferative activity against three cancer cell lines (MCF-7, HepG-2 and A549). Doxorubicin was used as a positive control. The most promising compounds 5, 6, 10a, 10b, 14b, 14c, and 17 showed up-regulation for BAX and down-regulation of Bcl-2, these findings proved their role as hopeful apoptotic inducers. In addition, the inhibitory activity against both wild EGFR^WT and mutant EGFR^L858R-TK for these derivatives revealed that compounds 5, 14c, and 17 have IC₅₀ value ranging from 85 nM to 71.5 nM against wild EGFR^WT and 37.85-41.19 nM against the mutant type, Lapatinib was used as a reference standard with IC₅₀ values of 31.8 nM and 39.53 nM, respectively. The most potent derivatives were subjected to further evaluation against double mutant EGFR ^L858R/T790M and showed good IC₅₀ values between (0.27-0.78 nM) compared to Lapatinib (0.18 nM) and Erlotinib (0.21 nM). Among them, thiazolo-thiadiazole adamantane derivative 17 exhibited the strongest inhibitory activity to the EGFR. Molecular docking studies were performed inside the active site of EGFR (1M17), and binding energy scores ranged between (-19.19 to -22.07 Kcal/mol) compared to Erlotinib (-19.10 Kcal/mol). Furthermore, oral bioavailability beside some pharmacokinetics properties of these derivatives were also investigated in this research work.

Design, synthesis, in vitro antimicrobial evaluation and molecular docking studies of indol-2-one tagged with morpholinosulfonyl moiety as DNA gyrase inhibitors

A series of Schiff bases 3, 5, 7 and hydrazones 9 were achieved via reaction of 5-(morpholinosulfonyl)indol-2,3-dione (1) with appropriate amines and/or hydrazide derivatives. Representative compounds of the synthesized products were tested and evaluated as antimicrobial agents. According to MIC and MBC results from compounds 9a, 9c, 7a, 3b, 3c, and 5b were able to exhibit significant antibacterial activity against both Gram-positive and Gram-negative bacteria together with moderate antifungal activities. Also, a multi-drug resistance study (MDRS) was carried out to evaluate the activity of most potent compounds, and these compounds showed considerable results compared with Norfloxacin and Tetracycline which observed no results against strains used in this study. The inhibitory activity of most potent compounds (3b, 3c, 5b, 7a, 9a, and 9c) against DNA gyrase isolated from S. aureus was examined. The results indicated that all of these derivatives inhibiting DNA gyrase and therefore lead to separate bacterial DNA and inhibit cell division. Compounds 3b, 9c showed to be very potent inhibitors towards S. aureus DNA gyrase with IC₅₀ values (18.75 ± 1.2 and 19.32 ± 0.99 µM) respectively, compared with Ciprofloxacin (26.43 ± 0.64 µM). Molecular docking studies indicated that the synthesized compounds observed good binding with the enzyme and showed lower binding energy of the most promising compounds than a standard drug used, and enabled a better understanding of their structural features.

Recent advances in isatin hybrids as potential anticancer agents

The isatin framework is a useful template for the development of novel anticancer agents. This is exemplified by the fact that several isatin-based anticancer agents, such as semaxanib, sunitinib, nintedanib, and hesperadin, are already in use or under clinical trials for the treatment of diverse kinds of cancers. Isatin-based hybrids could be obtained by incorporating other anticancer pharmacophores into the isatin skeleton and they have the potential to overcome drug resistance with reduced side effects. Thus, isatin-based hybrids may provide attractive scaffolds for the development of novel anticancer agents. This review covers the recent advances of isatin-based hybrids with anticancer activity, covering articles published between 2001 and 2019. The anticancer activities of these molecules and the structure-activity relationships are also discussed. The purpose of this review article is to set up the direction for the design and development of isatin-based hybrids with high efficacy and low toxicity.