Synthesis and biological evaluation of 2-amino-5-sulfanyl-1,3,4-thiadiazole derivatives as antidepressant, anxiolytics and anticonvulsant agents

Synthesis, biological and molecular modelling for 1,3,4-thiadiazole sulfonyl thioureas: bacterial and fungal activity

Some substituted thioureas (6a-i) containing a 1,3,4-thiadiazole ring were synthesized by the reaction of the corresponding substituted 2-amino-1,3,4-thiadiazoles 3a-i with p-toluenesulfonyl isocyanate in a one-pot procedure. The antibacterial and antifungal activities of these sulfonyl thioureas were estimated using a minimum inhibitory concentration protocol. Almost all the thioureas exhibited remarkable antimicrobial activity. Amongst the studied compounds, thioureas 6a, 6c, 6h, and 6i were better inhibitors against the bacterium S. aureus, with MIC values of 0.78-3.125 μg mL-1. These compounds were also tested for their inhibition against S. aureus enzymes, including enzymes of DNA gyrase, DNA topoisomerase IV (Topo IV), and dihydrofolate reductase. Amongst the compounds, 6h was a strong inhibitor, with IC50 values of 1.22, 53.78, and 0.23, respectively. Induced fit docking calculations were performed to observe the binding efficiency and steric interactions of these compounds. The obtained results showed that compound 6h was compatible with the active sites of S. aureus DNA gyrase 2XCS. This ligand interacted with residues ASP1083 (chain D), MET1121 (chain B), ARG1122 (chain D), and also with HOH2035, HOH2089, HOH2110, HOH2162. Molecular dynamics simulation in a water solvent system showed that the active interactions with residues ASP083 and MET1121 (chain B), along with ASP1083, MET1121, and ARG1122 (chain D), played an important role in stabilizing complex 6h/2XCS in the active pocket.

Indane-1,3-Dione: From Synthetic Strategies to Applications

Indane-1,3-dione is a versatile building block used in numerous applications ranging from biosensing, bioactivity, bioimaging to electronics or photopolymerization. In this review, an overview of the different chemical reactions enabling access to this scaffold but also to the most common derivatives of indane-1,3-dione are presented. Parallel to this, the different applications in which indane-1,3-dione-based structures have been used are also presented, evidencing the versatility of this structure.

New 1,3,4-thiadiazoles derivatives: synthesis, antiproliferative activity, molecular docking and molecular dynamics

Aim: A series of 1,3,4-thiadiazole himachalene hybrids were prepared from the treatment of a himachalen-4-one thiosemicarbazone derivative with N-aryl-C-ethoxycarbonyl-nitrilimines and diarylnitrilimines via a 1,3-dipolar cycloaddition reaction. Materials & methods: The structures were confirmed by NMR, IR and high-resolution mass spectroscopy (HRMS). Results & conclusion: The newly synthesized hybrid compounds were tested for their in vitro antitumor activities against a panel of cancer cell lines including fibrosarcoma (HT-1080), lung carcinoma (A-549) and breast carcinoma (MCF-7 and MDA-MB-231). Among the tested products, 4a showed excellent activity against the HT-1080 and MCF-7 cell lines with IC50 values of 11.18 ± 0.69 and 12.38 ± 0.63 μm, comparable to that of the reference drug. Docking results confirmed that the active inhibitors were well accumulated in the mushroom tyrosinase active site. Flow cytometry analysis indicated that hybrid 4a induced apoptosis and cell cycle arrest in the G0/G1 phase. Molecular modeling studies affirmed the intercalative binding of compound 4a in the active site.

1,3,4-Thiadiazole Scaffold: As Anti-Epileptic Agents

A wide range of biological activities is exhibited by 1,3,4-thiadiazole moiety such as antidiabetic, anticancer, anti-inflammatory, anticonvulsant, antiviral, antihypertensive, and antimicrobial. To date, drugs such as butazolamide, and acetazolamide. Several modifications have been done in the 1,3,4-thiadiazole moiety which showed good potency as anticonvulsant agents which are highly effective and have less toxicity. After in-depth literature survey in this review, we have compiled various derivatives of 1,3,4-thiadiazole scaffold as anticonvulsant agents.

Preparation and Thermogravimetric and Antimicrobial Investigation of Cd (II) and Sn (II) Adducts of Mercaptopyridine, Amino Triazole Derivatives, and Mercaptothiazoline Organic Ligand Moieties

The solid adducts of SnCl₂.(3amt).H₂O, SnCl₂.2(3amt).H₂O, CdCl₂.(3amt), CdCl₂.2(3amt), SnCl₂.(2mct).0.5H₂O, SnCl_2.2(2mct), CdCl₂.(2mct), CdCl₂.2(2mct).H₂O, SnCl₂.(2mcp).1.5H₂O, >₂.2(2mcp).4H₂O, CdCl₂.(2mcp), CdCl₂.2(2mcp), SnCl₂.(4amt).4H₂O, SnCl₂.2(4amt).1.5H₂O, CdCl₂.(4amt).H₂O, and CdCl₂.2(4amt) (where the 3amt, 4amt, 2mct, and 2mcp represent 3-amino-1,2,4-triazole, 4-amino-1,2,4-triazole, 2-mercaptothiazoline, and 2-mercaptopyridine simple organic chelates, respectively) were prepared using a solid-state route and investigated by CHN elemental analysis and infrared spectroscopy. Additionally, we investigated the thermogravimetric characterization and antimicrobial proprieties. It is verified that for 3amt and 4amt adducts, the coordination occurs through nitrogen atom. For 2mct compounds, the coordination occurs through nitrogen (Sn) or sulfur (Cd). For 2mcp adducts, both coordination sites nitrogen and sulfur are involved. By examination of TG curves, it is confirmed that for each hydrated compounds, the first mass loss step is linked with the release of water molecules followed by the release of ligand molecules and sublimation of the metal chloride. Furthermore, it is verified that, considering only the release of ligand molecules (3amp, 4amp, 2mct, or 2mcp), the cadmium adducts are always more stable than the correspondent tin adducts probably due to the formation of cross-linking bonds in these compounds. Finally, of these 16 adducts, 14 showed antimicrobial activities against different bacterial and fungal strains.

A series of 1,3-imidazoles and triazole-3-thiones based thiophene-2-carboxamides as anticancer agents: Synthesis and anticancer activity

By addition of semicarbazide or phenylhydrazine hydrochloride to thienoylisothiocyanate (1) resulted in building of thiosemicarbazide derivative (2), triazole derivative (4) and thiophene-2-carboxamide (5), respectively. Basic cyclization of compound 2 led to formation of oxadiazine (3). Synthesis of thiadiazine derivative (6) was achieved via reaction of compound 5 and maleic anhydride in triethyl amine. Heating of compound 5 with ethyl chloroacetate or sodium ethoxide produced thiadiazine derivative (7) and triazolethione (8), respectively. Thiosemicarbazide derivative 11 was synthesized by addition of nicotinic hydrazide to compound 1. Refluxing of compound 11 with lead acetate afforded triazole (13). Moreover, acid and base mediated cyclizations of compound 11 gave thiadiazole (12) and 1,2,4-triazolethione (14) throughout thiophene intermediate, respectively. Addition of ethyl 2-aminothiophene-3-carboxylate to compound 1 formed thiourea (15) which was refluxed with ethoxide giving thiophene-3-carboxylic acid (16). Lastly, nucleophilic addition of amino phenol or ethylene diamine to compound 1 yielded oxazine structure (18) and imidazole derivative (19), respectively. The yields of the synthesized compounds were 61-95%. The detailed synthesis and spectroscopic data of the new compounds are reported.

Synthesis of Some Novel Thiadiazole Derivative Compounds and Screening Their Antidepressant-Like Activities

Novel thiadiazole derivatives were synthesized through the reaction of acetylated 2-aminothiadiazole and piperazine derivatives. The chemical structures of the compounds were clarified by Infrared Spectroscopy (IR), ¹H Nuclear Magnetic Resonance Spectroscopy (¹H-NMR), ¹³C Nuclear Magnetic Resonance Spectroscopy (¹³C-NMR) and Electronspray Ionisation Mass Spectroscopy (ESI-MS) spectroscopic methods. Antidepressant-like activities were evaluated by the tail-suspension (TST) and modified forced swimming (MFST) methods. Besides, possible influence of the test compounds on motor activities of the animals were examined by activity cage tests. In the TST, administration of the compounds 2c, 2d, 2e, 2f, 2g and 2h significantly decreased the immobility time of mice regarding the control values. Further, in the MFST, the same compounds reduced the total number of immobility behaviors while increasing swimming performance. However, no change was observed in the total number of climbing behaviors. These data suggested that compounds 2c, 2d, 2e, 2f, 2g and 2h possess notable antidepressant-like activities. Reference drug fluoxetine (10 mg/kg) was also exhibited its antidepressant activity, as expected. No significant difference was seen between the locomotor activity values of the test groups signifying that observed antidepressant-like activities are specific. Theoretical calculation of absorption, distribution, metabolism, excretion (ADME) properties for the obtained compounds were performed and obtained data supported the antidepressant-like potential of these novel thiadiazole derivatives.

Synthesis and Evaluation of New 1,3,4-Thiadiazole Derivatives as Antinociceptive Agents

In the current work, new 1,3,4-thiadiazole derivatives were synthesized and investigated for their antinociceptive effects on nociceptive pathways of nervous system. The effects of these compounds against mechanical, thermal and chemical stimuli were evaluated by tail-clip, hot-plate and acetic acid-induced writhing tests, respectively. In addition, activity cage was performed to assess the locomotor activity of animals. The obtained data indicated that compounds 3b, 3c, 3d, 3e, 3g and 3h increased the reaction times of mice both in the hot-plate and tail-clip tests, indicating the centrally mediated antinociceptive activity of these compounds. Additionally, the number of writhing behavior was significantly decreased by the administration of compounds 3a, 3c, 3e and 3f, which pointed out the peripherally mediated antinociceptive activity induced by these four compounds. According to the activity cage tests, compounds 3a, 3c and 3f significantly decreased both horizontal and vertical locomotor activity of mice. Antinociceptive behavior of these three compounds may be non-specific and caused by possible sedative effect or motor impairments.

New heterocyclic compounds from 1,2,4-triazole and 1,3,4-thiadiazole class bearing diphenylsulfone moieties. Synthesis, characterization and antimicrobial activity evaluation

Some new 5-(4-(4-X-phenylsulfonyl)phenyl)-4-(R)-2H-1,2,4-triazol-3(4H)-thiones 4a,b; 5a,b and 5-(4-(4-X-phenylsulfonyl)phenyl)-N-(R)-1,3,4-thiadiazol-2-amines 6a,b; 7a,b were obtained by cyclization of new N(1)-[4-(4-X-phenylsulfonyl)benzoyl]-N(4)-(R)-thiosemicarbazides 2a,b; 3a,b (X=H, Br). The 1,2,4-triazoles were synthesized by intramolecular cyclization of acylthiosemicarbazides, in basic media. On the other hand, 1,3,4-thiadiazoles were obtained from same acylthiosemicarbazides, in acidic media. These new intermediates from thiosemicarbazide class were afforded by the reaction of 4-(4-X-phenylsulfonyl)benzoic acids hydrazides (X=H, Br) 1a,b with 4-trifluoromethoxyphenyl or 3,4,5-trimethoxyphenyl isothiocyanate. The newly synthesized compounds were characterized by IR, (1)H NMR, (13)C NMR, MS and elemental analysis. All the new compounds were screened for their antimicrobial activity against some bacteria (Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 13061, Escherichia coli ATCC 25922, Enterobacter cloacae ATCC 49141, Acinetobacter baumannii ATCC 19606 and Pseudomonas aeruginosa ATCC 27853) and yeasts (Candida albicans ATCC 90028 and Candida parapsilosis ATCC 22019).

Synthesis and antiviral activity of 5‑(4‑chlorophenyl)-1,3,4-thiadiazole sulfonamides

Starting from 4-chlorobenzoic acid, 10 new 5-(4-chlorophenyl)-N-substituted-N-1,3,4-thiadiazole-2-sulfonamide derivatives were synthesized in six-steps. Esterification of 4-chlorobenzoic acid with methanol and subsequent hydrazination, salt formation and cyclization afforded 5-(4-chlorophen-yl)-1,3,4-thiadiazole-2-thiol (5). Conversion of this intermediate into sulfonyl chloride 6, followed by nucleophilic attack of the amines gave the title sulfonamides 7a-7j whose structures were confirmed by NMR, IR and elemental analysis. The bioassay tests showed that compounds 7b and 7i possessed certain anti-tobacco mosaic virus activity.