Synthesis and PreliminaryIn-VitroCytotoxic Evaluation of Some Novelbis-Heterocycles Incorporating Thienothiophene

Recent synthetic approaches towards thienothiophenes: a potential template for biologically active compounds

Heterocyclic compounds are attractive candidates because of their vast applications in natural and physical sciences. Thienothiophene (TT) is an annulated ring of two thiophene rings with a stable and electron-rich structure. Thienothiophenes (TTs) fully represent the planar system, which can drastically alter or improve the fundamental properties of organic, π-conjugated materials when included into a molecular architecture. These molecules possessed many applications including, pharmaceutical as well as optoelectronic properties. Different isomeric forms of thienothiophene showed various applications such as antiviral, antitumor, antiglaucoma, antimicrobial, and as semiconductors, solar cells, organic field effect transistors, electroluminiscents etc. A number of methodologies were adopted to synthesize thienothiophene derivatives. In this review, we have addressed different synthetic strategies of various isomeric forms of thienothiophene that have been reported during last seven years, i.e., 2016-2022.

Synthesis of New Thiazole Clubbed Imidazo[2,1-b]thiazole Hybrid as Antimycobacterial Agents

Aims:

The study aims to synthesize bioactive hybrid pharmacophores (thiazole ring and imidazo[2,1-b]thiazole system) by incorporating them to one biological assessment molecular system.

Background:

Literature survey revealed that various imidazo[2,1-b]thiazoles, thiazoles and hydrazones have powerful anti-mycobacterial activity.

Objective:

This study demonstrates the effectiveness of molecular hybridization and the scope for imidazo[2,1-b]thiazole-hydrazone-thiazoles to develop as promising anti-mycobacterial agents.

Method:

Several imidazo[2,1-b]thiazole–hydrazine-thiazoles 5a-g, 7a,b, 9a,b, 11a,b, 13, and 15a,b were generated using a molecular hybridization strategy and assessed against Mycobacterium tuberculosis (ATCC 25618) for their in vitro antituberculous activity.

Result:

Derivative 7b (MIC = 0.98 μg/mL) has shown the most promising anti-mycobacterial activity among the series tested. Brief structure-activity relationship studies found that the thiazole of chlorophenyl or pyridine or coumarin had a significant relation with the anti-mycobacterial activity.

Conclusion:

Promising anti-mycobacterial activity of compound 7b compared with reference drug suggests that this compound may contribute as a lead compound in search of new potential anti-mycobacterial agents.

Synthesis, Molecular Docking Screening and Anti-Proliferative Potency Evaluation of Some New Imidazo[2,1-b]Thiazole Linked Thiadiazole Conjugates

BACKGROUND

Imidazo[2,1-b]thiazole scaffolds were reported to possess various pharmaceutical activities.

RESULTS

The novel compound named methyl-2-(1-(3-methyl-6-(p-tolyl)imidazo[2,1-b]thiazol-2-yl)ethylidene)hydrazine-1-carbodithioate 3 acted as a predecessor molecule for the synthesis of new thiadiazole derivatives incorporating imidazo[2,1-b]thiazole moiety. The reaction of 3 with the appropriate hydrazonoyl halide derivatives 4a-j and 7-9 had produced the respective 1,3,4-thiadiazole derivatives 6a-j and 10-12. The chemical composition of all the newly synthesized derivatives were confirmed by their microanalytical and spectral data (FT-IR, mass spectrometry, 1H-NMR and 13C-NMR). All the produced novel compounds were screened for their anti-proliferative efficacy on hepatic cancer cell lines (HepG2). In addition, a computational molecular docking study was carried out to determine the ability of the synthesized thiadiazole molecules to interact with active site of the target Glypican-3 protein (GPC-3). Moreover, the physiochemical properties of the synthesized compounds were derived to determine the viability of the compounds as drug candidates for hepatic cancer.

CONCLUSION

All the tested compounds had exhibited good anti-proliferative efficacy against hepatic cancer cell lines. In addition, the molecular docking results showed strong binding interactions of the synthesized compounds with the target GPC-3 protein with lower energy scores. Thus, such novel compounds may act as promising candidates as drugs against hepatocellular carcinoma.

Design, Synthesis, Molecular Docking Study and Anti-Hepatocellular Carcinoma Evaluation of New Bis-Triazolothiadiazines

OBJECTIVE

The reaction of bis(4-amino-4H-1,2,4-triazole-3-thiol) with hydrazonoyl halides and α-halo-ketones gave a new series of bis-1,2,4-triazolo[3,4-b]thiadiazine derivatives.

METHODS

The structure of the new products was established on the basis of their elemental and spectral data (mass, 1H NMR, 13C NMR and IR) and an alternate method.

RESULTS

Several of the synthesized products were subjected to in vitro anticancer screening against human hepatocellular carcinoma (HepG-2) and the results showed that compounds 16, 14 and 12 have promising activities (IC50 value of 24.8±9.1, 28.3±0.5, and 31±2.9μM, respectively) compared with Harmine reference drug (IC50 value of 22.4±1.11 μM).

CONCLUSION

Moreover, molecular docking studies were performed to analyze the binding modes of the discovered hits into the active site of DYRK1A using iGEMDOCK.

Tetrazole hybrids with potential anticancer activity

Cancer is one of the main causes of death throughout the world. The anticancer agents are indispensable for the treatment of various cancers, but most of them currently on the market are not specific, resulting in series of side effects of chemotherapy. Moreover, the emergency of drug-resistance towards cancers has already increased up to alarming level in the recent decades. Therefore, it's imperative to develop novel anticancer candidates with excellent activity against both drug-susceptible and drug-resistant cancers, and low toxicity as well. Tetrazole is the bioisoster of carboxylic acid, and its derivatives demonstrated promising anticancer activity. Hybridization of tetrazole with other anticancer pharmacophores may provide novel candidates with anticancer potency. The present review described the anticancer activity of tetrazole hybrids, and the structure-activity relationship (SAR) is also discussed to provide an insight for rational designs of tetrazole anticancer candidates with higher efficiency.

One Pot Single Step Synthesis and Biological Evaluation of Some Novel Bis(1,3,4-thiadiazole) Derivatives as Potential Cytotoxic Agents

A novel series of bis(1,3,4-thiadiazole) derivatives were synthesized in one step methodology with good yields by condensation reaction between bis-hydrazonoyl chloride 1 and various reagents. The structures of the prepared compounds were confirmed by spectral data (IR, NMR, and MS), and elemental analysis. The anticancer activity against human breast carcinoma (MCF-7) cancer cell lines was evaluated in MTT assay. The results revealed that the bis-thiadiazole derivatives 5c,d, 7b,c and 9c had higher antitumor activity than the standard drug Imatinib.