Synthesis and anti-inflammatory evaluation of some new acyl-hydrazones bearing 2-aryl-thiazole

Pharmacological Evaluation of Novel Hydrazide and Hydrazone Derivatives: Anti-Inflammatory and Analgesic Potential in Preclinical Models

Hydrazones, characterized by their C=N-NH functional group, are promising candidates in medicinal chemistry due to their ability to interact with biological targets. This study evaluated the anti-inflammatory and analgesic properties of N-pyrrolylcarbohydrazide (1) and four pyrrole hydrazone derivatives (1A-D) in male Wistar rats (6 weeks old). Anti-inflammatory activity was assessed using a carrageenan-induced paw edema model, while formalin, tail flick, and paw withdrawal tests evaluated analgesia. Compound 1 exhibited dose-dependent anti-inflammatory activity. At 20 mg/kg, significant edema reductions were observed at the 2nd (p = 0.035) and 3rd hours (p = 0.022), while at 40 mg/kg, reductions remained significant at the 2nd (p = 0.008) and 3rd hours (p = 0.046). Compound 1A showed pronounced effects at 20 mg/kg at the 2nd (p = 0.005), 3rd (p < 0.001), and 4th hours (p = 0.004). Other compounds demonstrated minimal or no activity. Analgesic evaluation revealed that at 40 mg/kg, compound 1 significantly reduced paw-licking time in the second phase (p = 0.038). Compounds 1B, 1C, and 1D exhibited transient effects in the first phase only (p < 0.05). Compound 1A lacked significant analgesic activity. The findings suggest that structural modifications may enhance efficacy for broader therapeutic applications.

Design, synthesis, anticancer activity and molecular docking of quinoline-based dihydrazone derivatives

Based on the biologically active heterocycle quinoline, we successfully synthesized a series of quinoline-based dihydrazone derivatives (3a-3d). 1H NMR, 13C NMR, ESI-HRMS, IR, element analysis, UV/Vis spectroscopy and fluorescence spectroscopy were performed to comprehensively characterize their chemical structures, spectral properties and stability. Nitrosamine impurities were not detected in 3a-3d, and the systemic toxicological assessment indicated that the toxicity of 3a-3d was lower. Furthermore, their anticancer activity was evaluated by MTT, AO/EB double staining, apoptosis detection and ROS detection. The time-dependent UV/Vis spectra revealed that 3a-3d had good stability in solution. For all the newly synthesized compounds, cytotoxic activities were carried out against human gastric cancer cell line BGC-823, human hepatoma cell line BEL-7402, human breast cancer cell line MCF-7 and human lung adenocarcinoma cell line A549 as well as human normal liver cell line HL-7702. MTT assay indicated that all the tested compounds exhibited important antiproliferative activity against selected cancer cell lines with IC50 values ranging from 7.01 to 34.32 μM, while none of them had obvious cytotoxic activity to human normal liver cell line HL-7702. Further, the most potent compound 3c displayed stronger antiproliferative activity against all the selected cancer cell lines than the clinically used anticancer agent 5-FU. Especially, 3b and 3c displayed cytotoxic activity against MCF-7 cells with IC50 values of 7.016 μM and 7.05 μM, respectively. AO/EB double staining, flow cytometry and ROS detection suggested that 3b and 3c could induce MCF-7 cell apoptosis in a dose-dependent manner. Molecular docking suggests that 3b and 3c could bind with DNA via partial insertion. Additionally, molecular docking also suggests that CDK2 may be one of the targets for 3b and 3c. In a word, 3b and 3c could be suitable candidates for further investigation as chemotherapeutic agents in cancer treatment.

Novel Synthesized Benzophenone Thiazole Hybrids Exhibited Ex Vivo and In Silico Anti-Inflammatory Activity

Novel benzophenone-thiazole hybrids with different substituents were synthesized and evaluated for anti-inflammatory activity using an ex vivo human whole-blood assay. All hybrids (3c and 5a-h) showed significant anti-inflammatory activity via prostaglandin E2 (PGE2) release inhibition. Moreover, 5c (82.8% of PGE2 inhibition), 5e (83.1% of PGE2 inhibition), and 5h (82.1% of PGE2 inhibition) were comparable to the reference drugs. Molecular docking revealed potential preferable binding to the active sites of cyclooxygenase 2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) enzymes. This study provides the first evidence that benzophenone-thiazole hybrids may also dock in mPGES-1, a new attractive anti-inflammatory drug target, besides providing promising ex vivo anti-inflammatory activity. Thus, the novel hybrids are promising anti-inflammatory lead compounds and highlight the significance of optimal substituent selection in the design of potent PGE2 inhibitors.

Chitosan nanoparticles of new chromone-based sulfonamide derivatives as effective anti-microbial matrix for wound healing acceleration

A new series of chromone and furochromone-based sulfonamide Schiff's base derivatives 3-12 were synthesized and evaluated for their antimicrobial activity against S. aureus, E. coli, C. albicans, and A. niger using agar diffusion method. Compound 3a demonstrated potent antimicrobial activities with MIC values of 9.76 and 19.53 μg/mL against S. aureus, E. coli and C. albicans, which is 2-fold and 4-fold more potent than neomycin (MIC = 19.53, 39.06 μg/mL respectively). To improve the effectiveness of 3a, it was encapsulated into chitosan nanoparticles (CS-3aNPs). The CS-3aNPs size was 32.01 nm, as observed by transmission electron microscope (TEM) images and the zeta potential value was 14.1 ± 3.07 mV. Encapsulation efficiency (EE) and loading capacity (LC) were 91.5 % and 1.6 %, respectively as indicated by spectral analysis. The CS-3aNPs extremely inhibited bacterial growth utilizing the colony-forming units (CFU). The ability of CS-3aNPs to protect skin wounds was evaluated in vivo. CS-3aNPs showed complete wound re-epithelialization, hyperplasia of the epidermis, well-organized granulation tissue formation, and reduced signs of wound infection, as seen through histological assessment which showed minimal inflammatory cells in comparison with untreated wound. Overall, these findings suggest that CS-3aNPs has a positive impact on protecting skin wounds from infection due to their antimicrobial activity.

Discovery of Novel Inhibitors of Cruzain Cysteine Protease of Trypanosoma cruzi

Chagas disease (CD) is a parasitic disease endemic in several developing countries. According to the World Health Organization, approximately 6-8 million people worldwide are inflicted by CD. The scarcity of new drugs, mainly for the chronic phase, is the main reason for treatment limitation in CD. Therefore, there is an urgent need to discover new targets for which new therapeutical agents could be developed. Cruzain cysteine protease (CCP) is a promising alternative because this enzyme exhibits pleiotropic effects by acting as a virulence factor, modulating host immune cells, and interacting with host cells. This systematic review was conducted to discover new compounds that act as cruzain inhibitors, and their effects in vitro were studied through enzymatic assays and molecular docking. Additionally, the advances and perspectives of these inhibitors are discussed. These findings are expected to contribute to medicinal chemistry in view of the design of new, safe, and efficacious inhibitors against Trypanosoma cruzi CCP detected in the last decade (2013-2022) to provide scaffolds for further optimization, aiming toward the discovery of new drugs.

Synthesis and characterization of novel acyl hydrazones derived from vanillin as potential aldose reductase inhibitors

In the polyol pathway, aldose reductase (AR) catalyzes the formation of sorbitol from glucose. In order to detoxify some dangerous aldehydes, AR is essential. However, due to the effects of the active polyol pathway, AR overexpression in the hyperglycemic state leads to microvascular and macrovascular diabetic problems. As a result, AR inhibition has been recognized as a potential treatment for issues linked to diabetes and has been studied by numerous researchers worldwide. In the present study, a series of acyl hydrazones were obtained from the reaction of vanillin derivatized with acyl groups and phenolic Mannich bases with hydrazides containing pharmacological groups such as morpholine, piperazine, and tetrahydroisoquinoline. The resulting 21 novel acyl hydrazone compounds were investigated as an inhibitor of the AR enzyme. All the novel acyl hydrazones derived from vanillin demonstrated activity in nanomolar levels as AR inhibitors with IC50 and KI values in the range of 94.21 ± 2.33 to 430.00 ± 2.33 nM and 49.22 ± 3.64 to 897.20 ± 43.63 nM, respectively. Compounds 11c and 10b against AR enzyme activity were identified as highly potent inhibitors and showed 17.38 and 10.78-fold more effectiveness than standard drug epalrestat. The synthesized molecules' absorption, distribution, metabolism, and excretion (ADME) effects were also assessed. The probable-binding mechanisms of these inhibitors against AR were investigated using molecular-docking simulations.

Anti-proliferative activity of nitroquinolone fused acylhydrazones as non-small cell human lung cancer agents

A new series of 8-nitroquinolone-based aromatic heterocyclic acyl hydrazones have been synthesised and characterised through various spectroscopic techniques. They were theoretically examined for molecular docking with various proteins related to the apoptosis of the non-small cell lung cancer cell line A549. The results indicate that the possible modes of interaction of all the synthesised compounds are compatible for use as anti-proliferative drugs. Also, the drug-likeness of the compounds was examined through theoretical ADMET analysis, which indicated good gastrointestinal absorption as well as low toxicity. Selected compounds were evaluated for their in vitro anti-cancer activity using A549, MCF-7 and HeLa cell lines through an MTT assay to determine cytotoxicity. Compounds 3c, 3a and 11c exhibited significant cytotoxicity towards A549 cells in the order of 3c (15.3 ± 0.7) > 3a (15.8 ± 0.1) > 11c (17.1 ± 0.2), whereas all the compounds show insignificant toxicity on normal human embryonic kidney cells up to a concentration of 200 μM. The best compounds among the series (3c and 11c) were chosen for further detection of apoptosis through fluorescence microscopic techniques using AO/EtBr and DAPI. The reduced DNA synthesis during the cell cycle was also investigated through flow cytometric techniques. The results indicate that the compounds possess significant anticancer properties due to the activation of the mitochondrial mediated intrinsic pathway.

Novel N-Acyl Hydrazone Compounds as Promising Anticancer Agents: Synthesis and Molecular Docking Studies

In this study, a new series of N-acyl hydrazones 7a-e, 8a-e, and 9a-e, starting from methyl δ-oxo pentanoate with different substituted groups 1a-e, were synthesized as anticancer agents. The structures of obtained target molecules were identified by spectrometric analysis methods (FT-IR, ¹¹H NMR, ¹³C NMR, and LC-MS). The antiproliferative activity of the novel N-acyl hydrazones was evaluated on the breast (MCF-7) and prostate (PC-3) cancer cell lines by an MTT assay. Additionally, breast epithelial cells (ME-16C) were used as reference normal cells. All newly synthesized compounds 7a-e, 8a-e, and 9a-e exhibited selective antiproliferative activity with high toxicity to both cancer cells simultaneously without any toxicity to normal cells. Among these novel N-acyl hydrazones, 7a-e showed the most potent anticancer activities with IC₅₀ values at 7.52 ± 0.32-25.41 ± 0.82 and 10.19 ± 0.52-57.33 ± 0.92 μM against MCF-7 and PC-3 cells, respectively. Also, molecular docking studies were applied to comprehend potential molecular interactions between compounds and target proteins. It was seen that the docking calculations and the experimental data are in good agreement.

Visiblelight-induced ternary electron donor-acceptor complex enabled synthesis of 2-(2-hydrazinyl) thiazole derivatives and the assessment of their antioxidant and antidiabetic therapeutic potential

A mild and eco-friendly visible-light-induced synthesis of 2-(2-hydrazinyl) thiazole from readily accessible thiosemicarbazide, carbonyl, and phenacyl bromide in the absence of a metal catalyst and/or any extrinsic photosensitizer is reported. This approach only requires a source of visible light and a green solvent at room temperature to produce the medicinally privileged scaffolds of hydrazinyl-thiazole derivatives in good to outstanding yields. Experimental studies support the in situ formation of a visible-light-absorbing, photosensitized colored ternary EDA complex. The next step is to prepare a pair of radicals in an excited state, which makes it easier to prepare thiazole derivatives through a SET and PCET process. DFT calculations additionally supported the mechanistic analysis of the course of the reaction. The antioxidant and antidiabetic properties of some of the compounds in the synthesized library were tested in vitro. All the investigated compounds demonstrated appreciable antioxidant activity, as evidenced by the reducing power experiment and the IC₅₀ values of the DPPH radical scavenging experiment. Furthermore, the IC₅₀ values for 4c, 4d, and 4g also demonstrated a strong α-amylase inhibitory effect.

In Vivo Toxicity, Redox-Modulating Capacity and Intestinal Permeability of Novel Aroylhydrazone Derivatives as Anti-Tuberculosis Agents

The emergence and spread of Mycobacterium tuberculosis strains resistant to many or all anti-tuberculosis (TB) drugs require the development of new compounds both efficient and with minimal side effects. Structure-activity-toxicity relationships of such novel, structurally diverse compounds must be thoroughly elucidated before further development. Here, we present the aroylhydrazone compounds (3a and 3b) regarding their: (i) acute and subacute toxicity in mice; (ii) redox-modulating in vivo and in vitro capacity; (iii) pathomorphology in the liver, kidney, and small intestine tissue specimens; and (iv) intestinal permeability. The acute toxicity test showed that the two investigated compounds exhibited low toxicity by oral and intraperitoneal administration. Changes in behavior, food amount, and water intake were not observed during 14 days of the oral administration at two doses of 1/10 and 1/20 of the LD₅₀. The histological examination of the different tissue specimens did not show toxic changes. The in vitro antioxidant assays confirmed the ex vivo results. High gastrointestinal tract permeability at all tested pH values were demonstrated for both compounds. To conclude, both compounds 3a and 3b are highly permeable with low toxicity and can be considered for further evaluation and/or lead optimization.

Horbachevsky Ternopil National Medical University, 1, Maidan Voli, Ternopil, Ukraine, Lviv Polytechnic National University, 12, S. Bandery St., Lviv, Ukraine, National University of Life and Environmental Sciences of Ukraine, Kyiv, Ukraine, Danylo Halytsky Lviv National Medical University, 69, Pekarska St., Lviv, Ukraine, Danylo Halytsky Lviv National Medical University, 69, Pekarska St., Lviv, Ukraine, Institute of Pharmacology and Toxicology, National Academy of Medical Sciences, 14, Anton Tsedik St., Kyiv, Ukraine. Synthesis of New 3-Morpholyl-Substituted 4-Aryl-2-Arylimino-2,3-Dihydrothiazole Derivatives and Their Anti-Inflammatory and Analgesic Activity

New 4-aryl-3-(morpholin-4-yl)-2-arylimino-2,3-dihydrothiazole derivatives 1.1-1.16 were obtained using the Hantzsch reaction by condensation of N-(morpholin-4-yl)-N'-arylthioureas with the corresponding α bromoacetophenones in alcohols. Synthesized hydrobromides 1.1-1.8 were formed as crystalline precipitates during the boiling of the reaction mixture. Bases 1.9-1.16 were obtained by neutralizing the corresponding hydrobromides with NH4OH solution. It has been proposed a possible mechanism of the reaction that is based on the study of the structure of the synthesized compounds. The structures of the synthesized compounds were confirmed by 1H NMR spectroscopy with its special techniques (NOESY and ROESY experiments). It has been shown the formation of the isomer 4-(4'-chlorophenyl)-3-(morpholin-4-yl)-2-(4'-chlorophenylamino)-2.3-dihydrothiazole on the basis of compound 1.14. Pharmacological screening of synthesized derivatives of 4-aryl-2-arylimino-2,3-dihydrothiazole compounds revealed the analgesic effect in the model of visceral pain caused by the introduction of acetic acid to white mice. The anti-inflammatory effect of the synthesized compounds was evaluated in vivo by reducing limb edema in rats with carrageenan-induced inflammation. Thus, the synthesized compounds have analgesic and anti-inflammatory activity.

Discovery and SAR Study of Quinoxaline–Arylfuran Derivatives as a New Class of Antitumor Agents

A novel class of quinoxaline–arylfuran derivatives were designed, synthesized, and preliminarily evaluated for their antiproliferative activities in vitro against several cancer cell lines and normal cells. The representative derivative QW12 exerts a potent antiproliferative effect against HeLa cells (IC50 value of 10.58 μM), through inducing apoptosis and triggering ROS generation and the accumulation of HeLa cells in vitro. Western blot analysis showed that QW12 inhibits STAT3 phosphorylation (Y705) in a dose-dependent manner. The BLI experiment directly demonstrated that QW12 binds to the STAT3 recombination protein with a KD value of 67.3 μM. Furthermore, molecular docking investigation showed that QW12 specifically occupies the pY+1 and pY-X subpocket of the SH2 domain, thus blocking the whole transmission signaling process. In general, these findings indicated that the study of new quinoxaline–aryfuran derivatives as inhibitors of STAT3 may lead to new therapeutic medical applications for cancer in the future.

Syntheses, Molecular Docking and Biological Evaluation of 2-(2- hydrazinyl)thiazoles as Potential Antioxidant, Anti-Inflammatory and Significant Anticancer Agents

BACKGROUND

Recently, researchers have worked on the development of new methods for the synthesis of bioactive heterocycles using polyethylene glycol as a green solvent. In this context, we report the synthesized 2-(2-hydrazinyl) thiazoles for their in vitro antioxidant, in vitro anti-inflammatory and in vitro anti-cancer activities.

OBJECTIVE

The objective of the study was to develop novel antioxidant, anti-inflammatory and anti-cancer drugs.

METHODS

At the outset, the condensation of substituted acetophenones 1, thiosemicarbazide 2, and α-haloketones 3 was carried out using PEG-400 (20 mL) in the presence of 5 mol% glacial acetic acid to afford thiosemicarbazones intermediate. Furthermore, these thiosemicarbazones were reacted with α-haloketones 3 to obtain appropriate 2-(2-hydrazinyl) thiazoles. The synthesized compounds were in vitro tested for their antioxidant, anti-inflammatory, and anti-cancer activity.

RESULTS

In vitro evaluation report showed that nearly all molecules possessed potential antioxidant activity against 2,2-Diphenyl-1-picrylhydrazyl (DPPH), nitric oxide (NO), superoxide radical (SOR) and hydrogen peroxide (H₂O₂) radical scavenging activity. Most 2-(2-hydrazinyl) thiazoles derivatives have shown potential anti-inflammatory activity as compared to diclofenac sodium as a reference standard. 2-(2-Hydrazinyl) thiazoles derivatives showed significant anticancer activity for human leukemia cell line K-562 compared to adriamycin as a reference standard.

CONCLUSION

All tested compounds showed potential 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging activity. Among the tested series, 4b, 4d and 4e exhibited good hydrogen peroxide and 4b, 4e, 4f and 4g showed excellent superoxide radical scavenging activity. In addition, the 4b, 4e and 4g compounds revealed potent in vitro anti-inflammatory activity against standard diclofenac sodium drug. 2-(2-Hydrazinyl) thiazole derivatives, such as 4c and 4d, showed significant anticancer activity against human leukemia cell line K-562. Thus, these molecules provide an interesting template for the design and development of new antioxidant, anti-inflammatory, and anti-cancer agents.

Thiazole: A Versatile Standalone Moiety Contributing to the Development of Various Drugs and Biologically Active Agents

For many decades, the thiazole moiety has been an important heterocycle in the world of chemistry. The thiazole ring consists of sulfur and nitrogen in such a fashion that the pi (π) electrons are free to move from one bond to other bonds rendering aromatic ring properties. On account of its aromaticity, the ring has many reactive positions where donor–acceptor, nucleophilic, oxidation reactions, etc., may take place. Molecules containing a thiazole ring, when entering physiological systems, behave unpredictably and reset the system differently. These molecules may activate/stop the biochemical pathways and enzymes or stimulate/block the receptors in the biological systems. Therefore, medicinal chemists have been focusing their efforts on thiazole-bearing compounds in order to develop novel therapeutic agents for a variety of pathological conditions. This review attempts to inform the readers on three major classes of thiazole-bearing molecules: Thiazoles as treatment drugs, thiazoles in clinical trials, and thiazoles in preclinical and developmental stages. A compilation of preclinical and developmental thiazole-bearing molecules is presented, focusing on their brief synthetic description and preclinical studies relating to structure-based activity analysis. The authors expect that the current review may succeed in drawing the attention of medicinal chemists to finding new leads, which may later be translated into new drugs.

Synthesis and Antimicrobial Activity of Novel Hydrazone and 1,2,4-Triazole-3-thione Derivatives

Abstract

Novel hydrazone and 1,2,4-triazole-3-thione derivatives were obtained via the reaction of N1,N3,2-triaryl-6-hydroxy-6-methyl-4-oxocyclohexane-1,3-dicarboxamides with acid hydrazides and thiosemicarbazide, respectively. Structure of the products was proved using IR and 1H NMR spectroscopy methods. Some of the synthesized compounds were tested for antimicrobial activity

F. Soliman A, Moatasim Y, El Taweel A, Abdelhameed MF, Bekheit MS, Ali MA, Girgis AS. Synthesis of aspirin-curcumin mimic conjugates of potential antitumor and anti-SARS-CoV-2 properties

Series of piperidone-salicylate conjugates were synthesized through the reaction of 3E,5E-bis(arylidene)-4-piperidones with the appropriate acid chloride of acetylsalicylate in the presence of triethylamine. All the synthesized conjugates reveal antiproliferative properties against A431 (squamous skin) cancer cell line with potency higher than that of 5-fluorouracil. Many of the synthesized agents also exhibit promising antiproliferative properties against HCT116 (colon) cancer cell line, of which 5o and 5c are the most effective with 12.9, 9.8 folds potency compared with Sunitinib. Promising activity is also shown against MCF7 (breast) cancer cell line with 1.19, 1.12 folds relative to 5-fluorouracil. PI-flow cytometry of compound 5c supports the arrest of cell cycle at G1-phase. However, compound 5o and Sunitinib arrest the cell cycle at S-phase. The synthesized conjugates can be considered as multi-targeted tyrosine kinase inhibitors due to the promising properties against VEGFR-2 and EGFR in MCF7 and HCT116. CDOCKER studies support the EGFR inhibitory properties. Compounds 5p and 5i possessing thienylidene heterocycle are anti-SARS-CoV-2 with high therapeutic indices. Many of the synthesized agents show enhanced COX-1/2 properties than aspirin with better selectivity index towards COX-2 relative to COX-1. The possible applicability of the potent candidates discovered as antitumor and anti-SARS-CoV-2 is supported by the safe profile against normal (non-cancer, RPE1 and VERO-E6) cells.

Synthesis, molecular docking and ADME studies of thiazole-thiazolidinedione hybrids as antimicrobial agents

New thiazole-thiazolidinedione hybrids (5a-k) were efficiently synthesized and evaluated for their in-vitro antimicrobial activity against four fungal and bacterial strains. The chemical structures of the compounds were elucidated by FTIR, ¹H NMR, and ¹³C NMR spectral data. Most of the synthesized compounds were sensitive against gram positive, gram negative bacterial and fungal strains. Among the synthesized molecules, compounds 5h, and 5i exhibited promising inhibitory activity against all selected fungal strains and gram positive bacteria namely, Staphylococcus aureus, and Enterococcus faecalis. The molecular docking results predicted that the thiazole-thiazolidinedione derivatives bind to the active site protein ATP-binding pocket from E. coli, S. aureus and C. albicans with good interaction energy scores. Ct-DNA was used to evaluate the binding interactions of the selected compounds by means of absorption spectroscopy. To further characterize the drug-likeness and ADME properties were calculated using the Qikprop, the result of present study suggests that thiazole-thiazolidinedione hybrid could be an interesting approach for the design of new antimicrobial agents.Communicated by Ramaswamy H. Sarma.

Synthesis and Biological Activity of Hydrazones and Derivatives: A Review

Hydrazones and their derivatives are very important compounds in medicinal chemistry due to their reported biological activity for the treatment of several diseases, like Alzheimer's, cancer, inflammation, and leishmaniasis. However, most of the investigations on hydrazones available in literature today are directed to the synthesis of these molecules with little discussion available on their biological activities. With the purpose of bringing lights into this issue, we performed a revision of the literature and wrote this review based on some of the most current research reports of hydrazones and derivatives, making it clear that the synthesis of these molecules can lead to new drug prototypes. Our goal is to encourage more studies focused on the synthesis and evaluation of new hydrazones, as a contribution to the development of potential new drugs for the treatment of various diseases.

Novel [1,2,3]triazolo[4,5-d]pyrimidine derivatives containing hydrazone fragment as potent and selective anticancer agents

In this paper, based on molecular hybridization, a series of [1,2,3]triazolo[4,5-d]pyrimidine derivatives containing hydrazine was synthesized and their antiproliferative activities against 5 cancer cell lines (MGC-803, PC3, PC9, EC9706 and SMMC-7721) were evaluated. We found that most of them exhibited obvious growth inhibition effects on these tested cancer cells, especially compound 34 on PC3 cells (IC₅₀ = 26.25 ± 0.28 nM). Meanwhile, compound 34 displayed best selectivity on PC3, compared with the other cancer cell lines, as well as excellent selectivity towards normal cell lines (Het-1A, L02 and GES-1). Further investigations demonstrated that 34 could significantly inhibit PC3 cells' colony formation, increase cellular ROS content, suppress EGFR expression and induce apoptosis. Our findings indicate that 34 may serve as a novel lead compound for the discovery of more triazolopyrimidine derivatives with improved anticancer potency and selectivity.

Design of balanced COX inhibitors based on anti-inflammatory and/or COX-2 inhibitory ascidian metabolites

The aim of this study was to design and synthesize COX-1/COX-2 balanced inhibitors incorporating the structural motifs of anti-inflammatory ascidian metabolites. We designed a series of substituted indole analogs that incorporate the key structures of the ascidian metabolites, herdmanines C and D. The synthesized analogs were tested for their inhibitory activity against COX-1 and COX-2, and compound 5m, which displayed balanced inhibition, was further evaluated for in vitro anti-inflammatory activity. Compound 5m suppressed the expression of pro-inflammatory factors, including iNOS, COX-2, TNF-α, and IL-6 in LPS-stimulated murine RAW264.7 macrophages. The reduction of PGE₂, NO, and ROS was also observed, together with the suppression of NF-κB, IKK, and IκBα phosphorylation. Our results characterized 5m as a COX-1/COX-2 balanced inhibitor that subsequently caused ROS inhibition and NF-κB suppression, and culminated in the suppression of iNOS, COX-2, TNF-α, and IL-6 expression.

Comparative Phytochemical Profile, Antioxidant, Antimicrobial and In Vivo Anti-Inflammatory Activity of Different Extracts of Traditionally Used Romanian Ajuga genevensis L. and A. reptans L. (Lamiaceae)

Several Ajuga species are used in Romanian folk medicine for their antioxidant, antimicrobial and anti-inflammatory properties, to treat pain, fever or arthritis. Still, the active compounds responsible for these effects and their mechanism of action are scarcely known. This research was designed to investigate the phytochemical profile (e.g. iridoids, polyphenolic compounds, phytosterols), as well as the biological potential (antioxidant, antibacterial, antifungal, anti-inflammatory properties) of two selected Ajuga species collected from different regions of Romanian spontaneous flora. The main compounds identified in A. reptans aerial parts extracts were 8-O-acetylharpagide, isoquercitrin and β-sitosterol, whilst in A. genevensis were 8-O-acetylharpagide, luteolin and campesterol. The extracts were screened for their antioxidant potential using different methods (DPPH, TEAC, EPR) and the results showed a good activity, in accordance with the polyphenol content (18-26 mg GAE/g dw). The antifungal activity on the tested strains was good. The determination of few parameters linked with the inflammatory mechanism allowed the assessment of in vivo anti-inflammatory potential. Ajuga reptans and A. genevensis ethanol extracts had anti-inflammatory activity through lowering the oxidative stress, phagocytosis, PMN and total leukocytes. The best anti-oxidative and anti-inflammatory activity was observed for the Ajuga reptans 100 mg dw/mL extract when compared with diclofenac, thus the dose could be correlated with the pharmacological effect. These findings provide substantial evidence that both selected Ajuga species have the potential to be valued as sources of phytochemicals in effective anti-inflammatory herbal preparations.

Design and Synthesis of New Benzophenone Derivatives with In Vivo Anti-Inflammatory Activity through Dual Inhibition of Edema and Neutrophil Recruitment

A series of novel benzophenone derivatives containing a thiazole heterocyclic nucleus were designed by molecular hybridization. Molecular docking studies have demonstrated the inhibitory potential of the designed compounds against cyclooxygenase (COX) isoenzymes. These compounds were synthesized, characterized, and evaluated for their anti-inflammatory properties by the croton oil-induced ear edema assay to examine their effect on both prostaglandin (PG) production and neutrophils recruitment. The thiazole derivatives displayed a potent effect in terms of reducing ear edema. The analysis suggested that the presence of 4-phenyl-2-hydrazinothiazole and the absence of C4'-OCH₃ on the benzophenone derivative structure are strongly related to the inhibition of PG production. In addition, the derivatives 2e, 3a and 3c concomitantly inhibit PG production and neutrophil recruitment, which may be a mechanism of action better than of common NSAIDs due to their inability to inhibit the neutrophil recruitment. Thus, these compounds can be considered as potential lead compounds toward the development of new anti-inflammatory drugs with an innovating mechanism of action.

Synthesis, in vitro and in vivo biological evaluation, COX-1/2 inhibition and molecular docking study of indole-N-acylhydrazone derivatives

The objective of this work was to obtain and evaluate anti-inflammatory in vitro, in vivo and in silico potential of novel indole-N-acylhydrazone derivatives. In total, 10 new compounds (3a-j) were synthesized in satisfactory yields, through a condensation reaction in a single synthesis step. In the lymphoproliferation assay, using mice splenocytes, 3a and 3b showed inhibition of lymphocyte proliferation of 62.7% (±3.5) and 50.7% (±2), respectively, while dexamethasone presented an inhibition of 74.6% (±2.4). Moreover, compound 3b induced higher Th2 cytokines production in mice splenocytes cultures. The results for COX inhibition assays showed that compound 3b is a selective COX-2 inhibitor, but with less potency when compared to celecoxib, and compound 3a not presented selectivity towards COX-2. The molecular docking results suggest compounds 3a and 3b interact with the active site of COX-2 in similar conformations, but not with the active site of COX-1, and this may be the main reason to the COX-2 selectivity of compound 3b. In vivo carrageenan-induced paw edema assays were adopted for the confirmation of the anti-inflammatory activity. Compound 3b showed better results in suppressing edema at all tested concentrations and was able to induce an edema inhibition of 100% after 5 h of carrageenan injection at the 30 mg kg^-1 dosage, corroborating with the COX inhibition and lymphoproliferation results. I addition to our experimental results, in silico analysis suggest that compounds 3a and 3b present a well-balanced profile between pharmacodynamics and pharmacokinetics. Thus, our preliminary results revealed the potentiality of a new COX-2 selective derivative in the modulation of the inflammatory process.

Synthesis, X-ray diffraction study and pharmacological evaluation of 3-amino-4-methylthiophene-2-acylcarbohydrazones

N-acylhydrazone is an interesting privileged structure that has been used in the molecular design of a myriad of bioactive compounds. In order to identify new antinociceptive drug candidates, we described herein the design, synthesis, X-ray diffraction study and the pharmacological evaluation of a series of 3-amino-4-methylthiophene-2-acylcarbohydrazone derivatives (8a-t). Compounds were prepared in good overall yields through divergent synthesis from a common key intermediate and were characterized by classical spectroscopy methods. X-ray diffraction study was employed for unequivocal determination of the imine double bond stereochemistry. 8a-t were evaluated in vivo through oral administration using the classical writhing test in mice. N-acylhydrazone derivatives 8j and 8l displayed relative potency similar to dipyrone, highlighting them as promising analgesic lead-candidates for further investigation.

Synthesis and antimicrobial activity of 3,4-dihydropyrimidin-2(1H)-one derivatives containing a hydrazone moiety

The title compounds were synthesized and characterized by IR,1H NMR,13C NMR and HRMS data. Their antimicrobial activities against bacterial strainsEscherichia coliand fungal strainsAspergillus nigerwere evaluated.

Phytochemical Composition, Antioxidant, Antimicrobial and in Vivo Anti-inflammatory Activity of Traditionally Used Romanian Ajuga laxmannii (Murray) Benth. ("Nobleman's Beard" - Barba Împăratului)

In the Romanian folk medicine, aerial parts of Ajuga laxmannii ("nobleman's beard," Romanian - "barba boierului" or "avrămească" or "creştinească") are traditionally used as galactagogue and anti-inflammatory agents. The present study aimed to evaluate the chemical composition (polyphenols, iridoids, and phytosterols), antioxidant, antimicrobial and in vivo anti-inflammatory activity of different extracts of A. laxmannii aerial parts. The major identified bioactive compounds were rutin, 8-O-acetylharpagide and β-sitosterol. The antioxidant activity of A. laxmannii extracts was evaluated using several methods, and the results showed good antiradical effects. Moreover, the antimicrobial evaluation showed a potent antifungal activity against C. albicans and P. funiculosum. Furthermore, the anti-inflammatory effect was determined by monitoring some parameters involved in the inflammatory process. The results obtained showed differences between the analyzed extracts; and therefore the importance of choosing the best solvent in order to extract the appropriate amount of bioactive compounds. A. laxmannii ethanol extract showed an anti-inflammatory effect by reducing total leukocytes, PMN, phagocytosis, and oxidative stress. Compared to diclofenac, only the 50 mg/mL A. laxmannii extract had better anti-inflammatory and anti-oxidative stress effects, and this could justify the importance of a correlation between the activity and the used concentration. These findings strongly suggest that A. laxmannii could be considered as a valuable source of bioactive compounds, which could be further valued as anti-inflammatory agents in the composition of several herbal drugs.

COX Inhibition Profile and Molecular Docking Studies of Some 2-(Trimethoxyphenyl)-Thiazoles

Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used therapeutic agents that exhibit frequent and sometimes severe adverse effects, including gastrointestinal ulcerations and cardiovascular disorders. In an effort to obtain safer NSAIDs, we assessed the direct cyclooxygenase (COX) inhibition activity and we investigated the potential COX binding mode of some previously reported 2-(trimethoxyphenyl)-thiazoles. The in vitro COX inhibition assays were performed against ovine COX-1 and human recombinant COX-2. Molecular docking studies were performed to explain the possible interactions between the inhibitors and both COX isoforms binding pockets. Four of the tested compounds proved to be good inhibitors of both COX isoforms, but only compound A3 showed a good COX-2 selectivity index, similar to meloxicam. The plausible binding mode of compound A3 revealed hydrogen bond interactions with binding site key residues including Arg120, Tyr355, Ser530, Met522 and Trp387, whereas hydrophobic contacts were detected with Leu352, Val349, Leu359, Phe518, Gly526, and Ala527. Computationally predicted pharmacokinetic profile revealed A3 as lead candidate. The present data prove that the investigated compounds inhibit COX and thus confirm the previously reported in vivo anti-inflammatory screening results suggesting that A3 is a suitable candidate for further development as a NSAID.

Synthesis and investigation of antimicrobial activities of nitrofurazone analogues containing hydrazide-hydrazone moiety

In this research we synthesized and tested for in vitro antimicrobial activity 21 nitrofurazone analogues. The compounds we obtained were identified on the basis of ¹H NMR and ¹³C NMR spectroscopy. The in vitro screening of antimicrobial properties of synthesized compounds revealed a wide spectrum of antimicrobial activity. Compounds 28, 29, 32–43, and 45–48 showed very high bactericidal effect towards Staphylococcus spp. ATTC and Bacillus spp. ATTC (MIC = 0.002–7.81 µg/ml and MBC = 0.002–31.25 µg/ml). The levels of activity of several compounds were far better than those of nitrofurantoin, ciprofloxacin or cefuroxime.

Cytotoxicity and Antioxidant Potential of Novel 2-(2-((1H-indol-5yl)methylene)-hydrazinyl)-thiazole Derivatives

Newly synthesized 2-(2-((1H-indol-5yl)methylene)-hydrazinyl)-thiazole derivatives were evaluated for their in vitro cytotoxicity on two carcinoma cell lines A2780 and HeLa. Significant cytotoxic activity for 2-(2-((1H-indol-5-yl)methylene)hydrazinyl)-4-methylthiazole (1) and 2-(2-((1H-indol-5-yl)methylene)hydrazinyl)-4-phenylthiazole (3), on both A2780 [IC₅₀: 11.6 μM (1), and 12.4 μM (3)] and HeLa [IC₅₀: 22.4 μM (1) and 19.4μM (3)] cell lines is reported. Their antioxidant potential was evaluated by spectrophotometric method, using DPPH radical or Fe (TPTZ)³⁺ complex, and EPR spectroscopy, therefore the compounds 1 and 3 showed remarkable antioxidant activity simultaneously with a cytotoxic effect on A2780 and HeLa cell lines. Furthermore, based on theoretical quantum chemical calculation, the present study analyzed the chemoselectivity of the hydrogen extraction from the indolyl-hydrazinil-thiazoles in reaction with free radicals.