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To this day, the quest to find new drugs is still a challenge due to the growing demands of patients suffering from chronic inflammatory diseases and the need for the individualization of therapy. The aim of this research was to synthesize new 1,2,4-triazole derivatives containing propanoic acid moiety and to investigate their anti-inflammatory, antibacterial and anthelmintic activity. Compounds 3a–3g were obtained in reactions of amidrazones 1a–1g with succinic anhydride. Several analyses of proton and carbon nuclear magnetic resonance (1H NMR, 13C NMR, respectively), as well as high-resolution mass spectra (HRMS), confirmed the structures of 1,2,4-triazole derivatives 3a–3g. Toxicity, antiproliferative activity and influence on cytokine release (TNF-α: Tumor Necrosis Factor-α, IL-6: Interleukin-6, IFN-γ: Interferon-γ, and IL-10: Interleukin-10) of the compounds 3a–3g were evaluated in peripheral blood mononuclear cells culture. Moreover, mitogen-stimulated cell culture was used for biological activity tests. The antimicrobial and anthelmintic activity of derivatives 3a–3g were studied against Gram-positive and Gram-negative bacterial strains and Rhabditis sp. culture. Despite the lack of toxicity, compounds 3a–3g significantly reduced the level of TNF-α. Derivatives 3a, 3c and 3e also decreased the release of IFN-γ. Taking all of the results into consideration, compounds 3a, 3c and 3e show the most beneficial anti-inflammatory effects.

A new Au(III) complex was synthesized from an amidrazone derivative and HAuCl4. Cyclization of amidrazone moiety lead to the 1,2,4-triazolo[1,5a]pyridine ring system, followed by Au(III) chelation. The crystal and molecular structure of the final compound was studied by single crystal X-ray diffraction as well as by 1H 13C and 1H 15N HMQC- and HMBC-NMR spectroscopy, which resulted in the assignment of all detected signals. This species was tested in vitro as an antibacterial and antiproliferative agent. It exhibited good antibacterial activity against Staphylococcus aureus and was proved to be more potent than amoxicillin against Bacillus subtilis and the drug resistant strain of Klebsiella pneumoniae. In contrast, its antiproliferative properties against cancer cell lines A549, HT-29, MV-4-11 and MCF-7 were relatively low.

Amidrazones are widely used in chemical synthesis, industry and agriculture. We compiled some of the most important findings on the biological activities of amidrazones described in the years 2010–2022. The data were obtained using the ScienceDirect, Reaxys and Google Scholar search engines with keywords (amidrazone, carbohydrazonamide, carboximidohydrazide, aminoguanidine) and structure strategies. Compounds with significant biological activities were included in the review. The described structures derived from amidrazones include: amidrazone derivatives; aminoguanidine derivatives; complexes obtained using amidrazones as ligands; and some cyclic compounds obtained from amidrazones and/or containing an amidrazone moiety in their structures. This review includes chapters based on compound activities, including: tuberculostatic, antibacterial, antifungal, antiparasitic, antiviral, anti-inflammatory, cytoprotective, and antitumor compounds, as well as furin and acetylocholinesterase inhibitors. Detailed information on the compounds tested in vivo, along the mechanisms of action and toxicity of the selected amidrazone derivatives, are described. We describe examples of compounds that have a chance of becoming drugs due to promising preclinical or clinical research, as well as old drugs with new therapeutic targets (repositioning) which have the potential to be used in the treatment of other diseases. The described examples prove that amidrazone derivatives are a potential source of new therapeutic substances and deserve further research.

1H-pyrrole-2,5-dione derivatives are known for their wide range of pharmacological properties, including anti-inflammatory and antimicrobial activities. This study aimed to synthesize new 3,4-dimethyl-1H-pyrrole-2,5-dione derivatives 2a–2f in the reaction of N3-substituted amidrazones with 2,3-dimethylmaleic anhydride and evaluate their structural and biological properties. Compounds 2a–2f were studied by the 1H-13C NMR two-dimensional techniques (HMQC, HMBC) and single-crystal X-ray diffraction (derivatives 2a and 2d). The anti-inflammatory activity of compounds 2a–2f was examined by both an anti-proliferative study and a production study on the inhibition of pro-inflammatory cytokines (IL-6 and TNF-α) in anti-CD3 antibody- or lipopolysaccharide-stimulated human peripheral blood mononuclear cell (PBMC) cultures. The antibacterial activity of compounds 2a–2f against Staphylococcus aureus, Enterococcus faecalis, Micrococcus luteus, Esherichia coli, Pseudomonas aeruginosa, Yersinia enterocolitica, Mycobacterium smegmatis and Nocardia corralina strains was determined using the broth microdilution method. Structural studies of 2a–2f revealed the presence of distinct Z and E stereoisomers in the solid state and the solution. All compounds significantly inhibited the proliferation of PBMCs in anti-CD3-stimulated cultures. The strongest effect was observed for derivatives 2a–2d. The strongest inhibition of pro-inflammatory cytokine production was observed for the most promising anti-inflammatory compound 2a.

Every year novel biologically active compounds are designed as antitumor agents. This review covers and highlights some of the most important findings described during 2018–2020 to appoint the benefits and drawbacks regarding the activity and toxicity of the metal-based cancer drug candidates. We review new multi-action platinum(IV) prodrugs and other metal complexes with high chemotherapeutic potential, which are designed to overcome cisplatin-resistant cancer cells. We also overview new complexes of Os(II), Ru(II), Ir(III), and Zn(II) used for photodynamic therapy, as well as the complexes conjugated with conventional drugs exhibiting new mechanisms of action. Promising complexes that exceed the selectivity of cisplatin, highly effective in vitro and in vivo, against certain types of neoplasms are distinguished in the lung, colon, liver, stomach, breast cancers and others.

A series of new linear trisubstituted N1-acylamidrazones have been investigated using a variety of analytical techniques and theoretical calculations to check the influence of the type of N1-acyl substituent on the resonance forms and conformational behavior in the solid state and in solution. The 1D- and 2D-NMR experiments, supported by computational studies, revealed that in solution all amidrazones exhibit conformational syn/anti isomerism that results from the hindered rotation around the amide bond. In the case of the propenoic acid derivative, the ROESY, HSQC, and HMBC experiments proved a third equilibrium structure that corresponds to the planar ylide form. The SC XRD data confirmed that the compounds tend to exist as Z-anti conformers of their hydrazone-amide tautomeric species in the solid state. The carboxyl-amide heterosynthon is favoured provided that the carboxyl group is not involved in the intramolecular hydrogen bonding. Interestingly, after replacement of the cyclic C1-substituent by the smaller propanoic acid unit, which results in lower steric hindrance, both syn and anti conformers can exist. Furthermore, in the former case both the neutral molecules and zwitterions are present in the single crystal. The relative stability of the distinct crystal forms was examined using TG-DSC methods supplemented with cohesive energy calculations (CRYSTAL). The results indicate that the unsolvated forms are stable in a wide range of temperatures; however, inclusion of solvent molecules makes them prone to cyclization at higher temperatures. This paper reports the first observation of temperature-induced cyclization of N1-acylamidrazone to its cyclic triazole derivative in the solid state.

Polymorphism of four biologically active 3-(4,5-diaryl-4H-1,2,4-triazole-3-yl)propenoic acid derivatives has been investigated. Traditional solution-based solid-state forms screening revealed three anhydrous forms of 3-[4-phenyl-5-(2-pyridyl)-4H-1,2,4-triazole-3-yl]propenoic acid. Noteworthy, two pairs of concomitant polymorphs were detected for this system. Two other compounds were found to be dimorphic. The molecular and crystal structures of all obtained crystal forms were established by single-crystal X-ray diffraction. The resulting crystal structures were analyzed in terms of molecular conformation, intermolecular interaction patterns, and crystal packing motifs. The experimental studies were supported by extended lattice and interaction energy calculations. It was found that the carboxylic group adopts the anti conformation in all studied forms and is involved in the intramolecular O–H···Ntriazole hydrogen bonding. In consequence, the association modes are dominated by the weak C–H···O, C–H···N hyd...

The series of 1,2,4-triazole derivatives containing methacrylic acid moiety were synthesized in reaction of N3-substituted amidrazones with itaconic anhydride. Preliminary calculated bioavailability parameters of obtained compounds suggested good penetration via cell membranes and their good absorption after oral intake. Antimicrobial evaluation in vitio showed diverse activity of obtained triazoles mainly on Gram-positive bacterial strains. One derivative was also examined to determine the effect on the central nervous system of mice.

Some reactions of selected chlorooxoesters and haloesters with a 1-allylthiourea under various conditions have been performed. The reactions have been performed in methanol in alkaline and neutral environment. Condensation of 1-allylthiourea with chlorooxoesters has been further led via acetal as intermediate compound. As a result, the compounds containing thiazole and a 4,5-dihydrothiazole ring with a good yield have been obtained. The structures of the compounds were verified by 1H NMR, 13C NMR as well as X-ray diffraction analysis. Due to the potential biological activity of the synthesized compounds, the parameters of their bioavailability have been determined, and the probability of pharmacological action has been defined. All of the obtained compounds fulfilled the rule of five, which indicate their good absorption after oral intake. The probability of pharmacological action and potential targets calculated for the obtained compounds show that they can be potential drugs. Graphical abstract

The series of new 1,2,4-triazole derivatives with methacrylic acid moiety were synthesized and characterized by NMR and IR spectroscopy as well as X-ray crystallography. The influence of newly synthesized compounds on the inflammation on the level of cytokine production and the proliferation of human peripheral blood mononuclear cells (PBMC) were experimentally evaluated. Obtained triazoles showed antiproliferative activity and diverse effects on cytokine production. Two compounds demonstrated potentially anti-inflammatory activity and comparable effects with ibuprofen.

2-Allylaminodihydrothiazole derivatives (III) are synthesized by condensation of allylthiourea (I) with haloesters (II) in alkaline medium, whereas 2-allylaminothiazole derivatives (V) are obtained by condensation of (I) with chlorooxoesters (IV) via acetal as intermediate compound, both of them with good yields.

A new linear amidrazone derivative, 6-acetyl-cyclohex-3-enecarboxylic acid [1-pyridin-2-yl-1-(pyridyn-2-yloamin)meth-(Z)-ylidene] hydrazide, H(2)L (2) and its Cu(II) complex, [Cu(2)L(2)]·4H(2)O (3) were synthesized and characterized by elemental analysis, IR and (1)H NMR spectroscopy and cyclic voltammetry. Compound 2 was synthesized in the equimolar reaction of N(3)-substituted amidrazone with cis-1,2,3,6-tetrahydrophthalic anhydride. The Cu complex of 2 was obtained in the reaction with copper(II) acetate. The molecular structures of 2 and 3 were determined by X-ray crystallography. The parent ligand exists in its amide-hydrazone form in the solid state. The central amidrazone moiety has a Z configuration with respect to the double C=N bond. Coordination to the metal center promotes Z/E isomerization of the hydrazone group of the ligand. Compound 3 is a dinuclear four-coordinated Cu(II) complex with the amidrazone ligand behaving as a tetradentate double deprotonated chelating one. Several biological activities of 2 and 3 were examined in vitro; they were: antimicrobial properties against selected bacterial and fungal strains, suppression of phytohemagglutinin A (PHA)-induced proliferation of human peripheral blood mononuclear cells (PBMC) and their effects on tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) production. The cytotoxic activity of Cu(II) complex was determined with respect to the four carcinoma cell lines (SW 984, CX-1, L-1210, A-431). The studied complex exhibited significant cytotoxic effects (particularly against CX-1 colon carcinoma), comparable to those reported for cisplatin. Both compounds have shown a relatively low antibacterial activity and were devoid of antifungal properties.

Two new 1,2,4-triazole-containing alkenoic acid derivatives were obtained from the reaction of N -phenyl-(pyridin-2-yl)carbohydrazonamide with itaconic anhydride, depending on the reaction conditions. The structures of 2-((4-phenyl-5-(pyridin-2-yl)-4 H -1,2,4-triazol-3-yl)methyl)acrylic acid or ( E )-2-methyl-3(4-phenyl-5-(pyridine-2-yl)-4 H -1,2,4-triazol-3-yl)acrylic acid were confirmed by means of 1D and 2D NMR spectroscopic data as well as by single-crystal X-ray diffraction analysis. The experiential 1 H and 13 C chemical shifts were compared with those calculated with B3LYP, EDF1, and EDF2 density functional theories. The theoretical study of the observed terminal-to-internal alkene isomerization was performed with density functional (DFT) B3LYP/6-31+G ∗ method using SM8 water and DMF solvation models. Antimicrobial activities of the newly prepared alkenoic acid derivatives were verified experimentally by a broth microdilution method.

A series of novel compounds were synthesized in reactions of N(3) -substituted amidrazones with cis-1,2-cyclohexanedicarboxylic anhydride: linear, isoindole, and triazole derivatives. All new structures were confirmed by H(1) NMR and IR spectrometry as well as elemental analysis. Potential biological effects of new compounds were predicted with the Prediction of Activity Spectra for Substances (PASS) program. Antiviral, antibacterial, analgesic, and anti-inflammatory activities were experimentally verified.