Rapid Synthesis of N-Tosylhydrazones under Solvent-Free Conditions and Their Potential Application Against Human Triple-Negative Breast Cancer

Iodine/DMSO-catalyzed oxidative deprotection of N-tosylhydrazone for benzoic acid synthesis

An oxidative deprotection of tosylhyrdazones has been demonstrated to afford benzoic acids using iodine and DMSO system. This efficient oxidative deprotection protocol offers exceptional functional group toleration under mild reaction conditions without any initiators or bases. Notably, the tosylhydrazone with the heteroaryl ring or with the aryl ring having base-sensitive hydroxyl and ester functional groups smoothly afforded the corresponding benzoic acid analogues under developed conditions. Moreover, this method features short reaction times, high product yields and easy purification by avoiding column-chromatographic purification.

N-H Insertion of Anilines on N-Tosylhydrazones Induced by Visible Light Irradiation

Diazo compounds and their precursors represent an interesting chemical category for organic synthesis. Particularly, N-tosylhydrazones have attracted attention for their easy accessibility and diverse reactivity, including carbene transfer reactions. We described a visible light-induced N-H insertion reaction of anilines on in situ-generated diazo compounds. Optimal conditions using DBU in toluene efficiently yielded the desired products. Mechanistic studies enabled us to trap a carbene intermediate that plays a key role in the transformation.

Molecular Hybrid Design, Synthesis, In Vitro Cytotoxicity, In Silico ADME and Molecular Docking Studies of New Benzoate Ester-Linked Arylsulfonyl Hydrazones

In this paper, we present the synthesis and characterization of two known sulfonyl hydrazides (1 and 2) and their new sulfonyl hydrazone derivatives (9-20), as well as in vitro and in silico investigations of their cytotoxic properties against human lung (A549) and human breast (MCF-7) cancer cell lines. The target compounds (9-20) obtained in high yields were synthesized for the first time by a multi-step reaction, and their structures were confirmed by elemental analysis and various spectral techniques, including FT-IR, 1H-, and 13C-NMR. The antiproliferative profiles of these compounds (1, 2, and 9-20) in this study were determined at concentrations of 200, 100, 50, and 25 µM against selected cancer cell lines for 72 h using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method. Except for compounds 1 and 2, other compounds (9-20) demonstrated cytotoxic activity at concentrations lower than 200 µM. The newly synthesized compounds (9-20) demonstrated antiproliferative activities at a micromolar level, with IC50 values in the range of 29.59-176.70 μM for the A549 cell line and 27.70-170.30 μM for the MCF-7 cell line. Among these compounds, compound 15 (IC50 = 29.59 μM against A549 cell line and IC50 = 27.70 μM against MCF-7 cell line) showed the highest cytotoxic activity against these two cancer cell lines compared to the reference drug cisplatin (IC50 = 22.42 μM against A549 cell line and IC50 = 18.01 μM against MCF-7 cell line). From docking simulations, to establish a plausible binding mode of compounds, we noticed that compound 15 demonstrated the highest affinity (-6.8508 kcal/mol) for estrogen receptor-beta (ERbeta) compared to others, suggesting promising ERbeta binding potential. Most compounds followed Lipinski's rule of five, with acceptable logP values. Additionally, all had mixed gastrointestinal absorption and limited blood-brain barrier permeability. Overall, our study proposed new sulfonyl hydrazones as a potential class of anticancer agents.

N-Heterocyclic Carbene-Catalyzed Facile Synthesis of Phthalidyl Sulfonohydrazones: Density Functional Theory Mechanistic Insights and Docking Interactions

N-heterocyclic carbene catalysis reaction protocol is disclosed for the synthesis of phthalidyl sulfonohydrazones. A broad range of N-tosyl hydrazones react effectively with phthalaldehyde derivatives under open-air conditions, enabling the formation of a new C-N bond via an oxidative path. The reaction proceeds under mild reaction conditions with broad substrate scopes, wide functional group tolerance, and good to excellent yields. The mechanistic pathway is studied successfully using control experiments, competitive reactions, ESI-MS spectral analyses of the reaction mixture, and computational study by density functional theory. The potential use of one of the phthalidyl sulfonohydrazone derivatives as the inhibitor of β-ketoacyl acyl carrier protein synthase I of Escherichia coli is investigated using molecular docking.

Novel Arylsulfonylhydrazones as Breast Anticancer Agents Discovered by Quantitative Structure-Activity Relationships

Breast cancer (BC) is the second leading cause of cancer death in women, with more than 600,000 deaths annually. Despite the progress that has been made in early diagnosis and treatment of this disease, there is still a significant need for more effective drugs with fewer side effects. In the present study, we derive QSAR models with good predictive ability based on data from the literature and reveal the relationships between the chemical structures of a set of arylsulfonylhydrazones and their anticancer activity on human ER+ breast adenocarcinoma and triple-negative breast (TNBC) adenocarcinoma. Applying the derived knowledge, we design nine novel arylsulfonylhydrazones and screen them in silico for drug likeness. All nine molecules show suitable drug and lead properties. They are synthesized and tested in vitro for anticancer activity on MCF-7 and MDA-MB-231 cell lines. Most of the compounds are more active than predicted and show stronger activity on MCF-7 than on MDA-MB-231. Four of the compounds (1a, 1b, 1c, and 1e) show IC50 values below 1 μM on MCF-7 and one (1e) on MDA-MB-231. The presence of an indole ring bearing 5-Cl, 5-OCH3, or 1-COCH3 has the most pronounced positive effect on the cytotoxic activity of the arylsulfonylhydrazones designed in the present study.

Development of New Antimycobacterial Sulfonyl Hydrazones and 4-Methyl-1,2,3-thiadiazole-Based Hydrazone Derivatives

Fifteen 4-methyl-1,2,3-thiadiazole-based hydrazone derivatives 3a–d and sulfonyl hydrazones 5a–k were synthesized. They were characterized by ¹H-NMR, ¹³C NMR, and HRMS. Mycobacterium tuberculosis strain H37Rv was used to assess their antimycobacterial activity. All compounds demonstrated significant minimum inhibitory concentrations (MIC) from 0.07 to 0.32 µM, comparable to those of isoniazid. The cytotoxicity was evaluated using the standard MTT-dye reduction test against human embryonic kidney cells HEK-293T and mouse fibroblast cell line CCL-1. 4-Hydroxy-3-methoxyphenyl substituted 1,2,3-thiadiazole-based hydrazone derivative 3d demonstrated the highest antimycobacterial activity (MIC = 0.0730 µM) and minimal associated cytotoxicity against two normal cell lines (selectivity index SI = 3516, HEK-293, and SI = 2979, CCL-1). The next in order were sulfonyl hydrazones 5g and 5k with MIC 0.0763 and 0.0716 µM, respectively, which demonstrated comparable minimal cytotoxicity. All compounds were subjected to ADME/Tox computational predictions, which showed that all compounds corresponded to Lipinski’s Ro5, and none were at risk of toxicity. The suitable scores of molecular docking performed on two crystallographic structures of enoyl-ACP reductase (InhA) provide promising insight into possible interaction with the InhA receptor. The 4-methyl-1,2,3-thiadiazole-based hydrazone derivatives and sulfonyl hydrazones proved to be new classes of lead compounds having the potential of novel candidate antituberculosis drugs.

Novel 2,4,6-Trimethylbenzenesulfonyl Hydrazones with Antibacterial Activity: Synthesis and In Vitro Study

This research describes the synthesis and in vitro antimicrobial activity study of a series of 2,4,6-trimethylbenzenesulfonyl hydrazones. Twenty-five hydrazones (2-26) were synthesized on the basis of condensation reaction. The in vitro bioactivity study confirmed the potential application of obtained derivatives as antimicrobial agents. Among the tested compounds, the highest activity was discovered for derivative 24, which possessed minimal inhibitory concentration (MIC) ranging from 7.81 to 15.62 µg/mL against Gram-positive reference bacterial strains. Synthesized benzenesulfonyl hydrazones can be applied as potential ligands for the synthesis of bioactive metal complexes.

Rapid Synthesis of N-Tosylhydrazones under Solvent-Free Conditions and Their Potential Application Against Human Triple-Negative Breast Cancer

Some N-tosylhydrazone derivatives were effectively synthesized under solvent-free conditions by using a grinding method at room temperature. The short reaction time, clean and mild process with simple workup and easy purification of the target compounds were salient features of the present protocol, which enables straightforward access to N-tosylhydrazones. Among the tosylhydrazone derivatives evaluated, compound 3 l exhibits excellent apoptosis-promoting and anticancer potential against triple-negative breast cancer (TNBC) cell lines. This research shows that our synthesized compound 3 l may be a desirable and effective therapeutic drug against TNBC.