18087-41-7

Upstream product

• 79-19-6 thiosemicarbazide 
• 2642-63-9 3',4'-dichloroacetophenone 

Relevant academic research and scientific papers

Structural design, synthesis and pharmacological evaluation of thiazoles against Trypanosoma cruzi

Chagas disease is one of the most significant health problems in the American continent. benznidazole (BDZ) and nifurtimox (NFX) are the only drugs approved for treatment and exhibit strong side effects and ineffectiveness in the chronic stage, besides different susceptibility among T. cruzi DTUs (Discrete Typing Units). Therefore, new drugs to treat this disease are necessary. Thiazole compounds have been described as potent trypanocidal agents. Here we report the structural planning, synthesis and anti-T. cruzi evaluation of a new series of 1,3-thiazoles (7–28), which were designed by placing this heterocycle instead of thiazolidin-4-one ring. The synthesis was conducted in an ultrasonic bath with 2-propanol as solvent at room temperature. By varying substituents attached to the phenyl and thiazole rings, substituents were observed to retain, enhance or greatly increase their anti-T. cruzi activity. In some cases, methyl at position 5 of the thiazole (compounds 9, 12 and 23) increased trypanocidal property. The exchange of phenyl for pyridinyl heterocycle resulted in increased activity, giving rise to the most potent compound against the trypomasigote form (14, IC50trypo = 0.37 μM). Importantly, these new thiazoles were toxic for trypomastigotes without affecting macrophages and cardiomyoblast viability. The compounds were also evaluated against cruzain, and five of the most active compounds against trypomastigotes (7, 9, 12, 16 and 23) inhibited more than 70% of enzymatic activity at 10 μM, among which compound 7 had an IC50 in the submicromolar range, suggesting a possible mechanism of action. In addition, examination of T. cruzi cell death showed that compound 14 induces apoptosis. We also examined the activity against intracellular parasites, revealing that compound 14 inhibited T. cruzi infection with potency similar to benznidazole. The antiparasitic effect of 14 and benznidazole in combination was also investigated against trypomastigotes and revealed that they have synergistic effects, showing a promising profile for drug combination. Finally, in mice acutely-infected with T. cruzi, 14 treatment significanty reduced the blood parasitaemia and had a protective effect on mortality. In conclusion, we report the identification of compounds (7), (12), (15), (23) and (26) with similar trypanocidal activity of benznidazole; compounds (9) and (21) as trypanocidal agents equipotent with BDZ, and compound 14 with potency 28 times better than the reference drug without affecting macrophages and cardiomyoblast viability. Mechanistically, the compounds inhibit cruzain, and 14 induces T. cruzi cell death by an apoptotic process, being considered a good starting point for the development of new anti-Chagas drug candidates.

Structural design, synthesis and pharmacological evaluation of 4-thiazolidinones against Trypanosoma cruzi

Chagas disease is an infection caused by protozoan Trypanosoma cruzi, which affects approximately 8-10 million people worldwide. Benznidazole is the only drug approved for treatment during the acute and asymptomatic chronic phases of Chagas disease; howev

Synthesis, anti-HIV activity, molecular modeling study and QSAR of new designed 2-(2-arylidenehydrazinyl)-4-arylthiazoles

Taking into consideration the eminence of 1,3-thiazoles in medicinal chemistry and in a view of procuring more pronounced biological contour, the synthesis of 2-(2-arylidenehydrazinyl)-4-arylthiazoles 6–43 was made possible by the cyclization reaction of thiosemicarbazones and α-bromoacetophenones. The thiosemicarbazones 5a-m were in turn synthesized from substituted benzaldehydes or acetophenones and thiosemicarbazide. Optimization of the reaction conditions was carried out in order to attain the target molecules in good yields. All the new compounds were evaluated in vitro for their antiviral activity against the replication of HIV-1 and HIV-2 in MT4 cells using a MTT assay. Screening results indicated that compounds 32–34 are the only compounds in the series inhibiting HIV-1 and HIV-2 replication in cell cultures with IC50 of >2.71, >2.19 and > 1.71 μM, respectively. The molecular docking of compounds 32 and 34 with some amino acids of human immunodeficiency virus reverse transcriptase (HIV RT) were also studied. The preliminary quantum structure-activity relationship (QSAR) among the newly synthesized congeners was obtained by two methods, Multiple Linear Regression (MRL) and Genetic Function Approximation (GFA).

Cyclopalladated complexes containing tridentate thiosemicarbazone ligands of biological significance: Synthesis, structure and antimalarial activity

The C-H activation reaction of two aryl-derived thiosemicarbazones with K2[PdCl4] affords tetranuclear cyclopalladated complexes (3 and 4) where the thiosemicarbazone ligand acts as a tridentate donor [C,N,S] coordinated to palladium via the ortho-carbon of the aryl ring, imine nitrogen and thiolato sulfur. The palladium-sulfur bridging coordination bonds give rise to a Pd4S4 core. These Pd-Sbridging bonds were cleaved with a variety of mono-and bis-phosphines to give a series of mono, di and tetranuclear organopalladium complexes (5-12) where the phosphorus atom coordinates to palladium trans to the imine nitrogen. All of the complexes were fully characterized using various analytical and spectroscopic techniques. These palladium complexes along with their free ligands were evaluated as bioorganometallic antimalarial agents against two Plasmodium falciparum strains, 3D7 (chloroquine sensitive) and K1 (chloroquine and pyrimethamine resistant). Some of the complexes were found to be moderate inhibitors of parasite growth and were more active than the corresponding free ligand.