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The Clp protease is an AAA+ protease that executes abnormally folded or malfunctioning proteins, and has an important role in producing virulence factors, forming biofilms or persisters and developing methicillin-resistant Staphylococcus aureus (MRSA). Recent studies showed that Clp protease controls virulence via agr signaling and degrades antitoxins of the toxin–antitoxin system to modulate the formation of persisters and biofilms. In this review, we focus on recent developments concerning the virulence and persistence regulatory pathways and resistance-related mechanism of Clp protease in S. aureus, with an overview of the Clp modulators developed to treat MRSA infection.

Nuclear export factor chromosome region maintenance 1 (CRM1) is an attractive anticancer and antiviral drug target that spurred several research efforts to develop its inhibitor. Noncovalent CRM1 inhibitors are desirable, but none is reported to date. Here, we present the crystal structure of yeast CRM1 in complex with S109, a substructure of CBS9106 (under clinical test). Superimposition with the LFS-829 (another covalent CRM1 inhibitor) complex inspired the design of a noncovalent CRM1 inhibitor. Among nine synthesized compounds, noncovalent CRM1 inhibitor 1 (NCI-1) showed a high affinity to human and yeast CRM1 in the absence or presence of GST-bound Ras-related nuclear protein (RanGTP). Unlike covalent inhibitors, the crystal structure showed that NCI-1 is bound in the "open" nuclear export signal (NES) groove of CRM1, simultaneously occupying two hydrophobic pockets. NCI-1 additionally inhibited the nuclear export and proliferation of cells harboring the human CRM1-C528S mutant. Our work opens up the avenue of noncovalent CRM1 inhibitor development toward a more potent, less toxic, and broad-spectrum anticancer/antiviral therapy.

Proteostasis is the process of regulating intracellular proteins to maintain the balance of the cell proteome, which is crucial for cancer cell survival. Several proteases located in the cytoplasm, mitochondria, lysosome, and extracellular environment have been identified as potential antitumor targets because of their involvement in proteostasis. Although the discovery of small-molecule inhibitors targeting proteases faces particular challenges, rapid advances in chemical biology and structural biology, and the new technology of drug discovery have facilitated the development of promising protease modulators. In this review, the protein structure and function of important tumor-related proteases and their inhibitors are presented. We also provide a prospective on advances and the outlook of new drug strategies that target these proteases.

Caseinolytic protease P (ClpP) is considered as a promising target for the treatment of Staphylococcus aureus infections. In an unbiased screen of 2632 molecules, a peptidomimetic boronate, MLN9708, was found to be a potent suppressor of SaClpP function. A time-saving and cost-efficient strategy integrating in silico position scanning, multistep miniaturized synthesis, and bioactivity testing was deployed for optimization of this hit compound and led to fast exploration of structure-activity relationships. Five of 150 compounds from the miniaturized synthesis exhibited improved inhibitory activity. Compound 43Hf was the most active inhibitor and showed reversible covalent binding to SaClpP while did not destabilize the tetradecameric structure of SaClpP. The crystal structure of 43Hf-SaClpP complex provided mechanistic insight into the covalent binding mode of peptidomimetic boronate and SaClpP. Furthermore, 43Hf could bind endogenous ClpP in S. aureus cells and exhibited significant efficacy in attenuating S. aureus virulence in vitro and in vivo.

Background Limitations of current intracanal irrigants such as sodium hypochlorite (NaOCl) and chlorhexidine (CHX) necessitate the development of novel antimicrobial agents to control endodontic infection. Aim This study investigated the antimicrobial activities of a small molecule II-6s against Enterococcus faecalis associated with endodontic diseases. Methods The susceptibility of E. faecalis to II-6s was evaluated by the microdilution method and time-kill assay. Microbial resistance was assessed by repeated exposure of E. faecalis to II-6s. Cytotoxicity of II-6s was evaluated by CCK-8 assay. Virulence gene expression of the II-6s-treated E. faecalis cells was measured by RT-qPCR. Bacterial reductions in the dentinal tubules were further assessed by confocal laser scanning microscopy. Results II-6s exhibited potent antimicrobial activity against E. faecalis and down-regulated virulence-associated genes in E. faecalis. II-6s induced no drug resistance in E. faecalis with lower cytotoxicity as compared to NaOCl and CHX. More importantly, 0.003125% II-6s exhibited significant bactericidal effect against E. faecalis residing in the dentinal tubules, which was comparable to 5.25% NaOCl and 2% CHX. Conclusions II-6s has excellent antimicrobial activity, moderate cytotoxicity and induces no drug resistance, and thus is a promising agent for the treatment of endodontic infection.

The emergence of various drug-resistant Mycobacterium tuberculosis (Mtb) strains has necessitated the exploration of new drugs that lack cross-resistance with existing therapeutics. By screening the MedChemExpress bioactive compound library, ceritinib was identified as a compound with activity against Mtb H37Ra. Ceritinib had a MIC value of 9.0 μM in vitro and demonstrated in vivo efficacy in a BALB/c mouse model infected with autoluminescent H37Ra. Then, 32 novel ceritinib derivatives were synthesized, and their antimycobacterial activities were evaluated in vitro. The antimycobacterial activities of the synthesized compounds were drastically affected by substitutions at position 4 of the pyrimidine nucleus and were enhanced by the presence of 2-isopropoxy-5-methyl-4-(piperidin-4-yl)aniline at position 2 of the pyrimidine nucleus. The in vivo antitubercular activities of the three most potent compounds were evaluated. 5-Chloro-N2-(2-isopropoxy-5-methyl-4-(piperidin-4-yl) phenyl)-N4-(naph thalen-1-yl) pyrimidine-2,4-diamine (16j) remarkably reduced the Mtb burden of mice. This result suggested the potential of 16j as a novel drug with superior antitubercular activities. The results of experiments on the combination of sulfamethoxazole with 16j and in silico modeling suggest that dihydrofolate reductase is the potential molecular target of 16j.

Background: The side effects of present antimicrobials like chlorhexidine (CHX) and the emergence of drug resistance necessitate the development of alternative agents to control dental caries. Aim: This study developed a novel small molecule, namely II-6s, and investigated its antimicrobial activities against common oral streptococci associated with dental caries. Methods: The susceptibility of streptococci to II-6s was evaluated by the microdilution method, time-kill assay and scanning electron microscopy. The exopolysaccharides, dead/live bacteria and bacterial composition of the II-6s-treated Streptococcus mutans/Streptococcus gordonii/Streptococcus sanguinis 3-species biofilms were analyzed by confocal laser scanning microscopy, fluorescent in situ hybridization and quantitative PCR. The anti-demineralization effect and cytotoxicity of II-6s were evaluated by transverse microradiography and CCK-8 assay, respectively. Repeated exposure of S. mutans to II-6s was performed to assess if II-6s could induce drug resistance. Results: II-6s exhibited antimicrobial activity similar to CHX against S. mutans, S. gordonii and S. sanguinis and significantly inhibited exopolysaccharides production, live bacteria and the demineralizing capability of the 3-species streptococcal biofilms. Besides, II-6s showed reduced cytotoxicity relative to CHX and did not induce drug resistance in S. mutans after 15 passages. Conclusion: - II-6s may serve as a promising part of a successful caries management plan.

Ribosomes, which synthesize proteins, are critical organelles for the survival and growth of bacteria. About 60% of approved antibiotics discovered so far combat pathogenic bacteria by targeting ribosomes. However, several issues, such as drug resistance and toxicity, have impeded the clinical use of ribosome-targeting antibiotics. Moreover, the complexity of the bacteria ribosome structure has retarded the discovery of new ribosome-targeting agents that are considered as the key to the drug-resistance and toxicity. To deal with these challenges, efforts such as medicinal chemistry optimization, combination treatment, and new drug delivery system have been developed. But not enough, the development of structural biology and new screening methods bring powerful tools, such as cryo-electron microscopy technology, advanced computer-aided drug design, and cell-free in vitro transcription/translation systems, for the discovery of novel ribosome-targeting antibiotics. Thus, in this paper, we overview the research on different aspects of bacterial ribosomes, especially focus on discussing the challenges in the discovery of ribosome-targeting antibacterial drugs and advances made to address issues such as drug-resistance and selectivity, which, we believe, provide perspectives for the discovery of novel antibiotics.

Human caseinolytic protease P (HsClpP), an ATP-dependent unfolding peptidase protein in the mitochondrial matrix, controls protein quality, regulates mitochondrial metabolism, and maintains the integrity and enzyme activity of the mitochondrial respiratory chain (RC). Studies show that abnormalities in HsClpP lead to mitochondrial dysfunction and various human diseases. In this review, we provide a comprehensive overview of the structure and biological function of HsClpP, and the involvement of its dysexpression or mutation in mitochondria for a panel of important human diseases. We also summarize the structural types and binding modes of known HsClpP modulators. Finally, we discuss the challenges and future directions of HsClpP targeting as promising approach for the treatment of human diseases of mitochondrial origin.

Aberrant activation of ERK signaling pathway usually leads to oncogenesis, and small molecular agents targeting this pathway are impeded by the emergence of drug resistance due to reactivation of ERK signaling. Compound DEL-22379 has been reported to inhibit ERK dimerization which was unaffected by drug-resistant mechanism reactivating the ERK signaling. Here, we discussed a structure-activity relationship study of DEL-22379. Forty-seven analogues were designed and synthesized. Each synthesized compound was biologically evaluated for their inhibitory rates on several tumor cell lines and compounds with high inhibitory rates were further evaluated for IC50 values. The structure-activity relationship of idolin-2-one scaffold and the impact of Z/E configuration on potency were discussed. Potential safety of two synthesized analogues was investigated and in silico docking study of five compounds was performed to understand the structural basis of ERK dimerization inhibition.

The mechanisms underlying the pathophysiology of depression remain elusive, and the development of novel, effective antidepressant drugs remains necessary. A dihydroquinoline analog of agomelatine (AGO), N-(2-(7-methoxy-3,4-dihydroisoquinolin-1-yl)ethyl)acetamide hydrochloride (NMDEA), was synthesized by employing a scaffold-hopping strategy in our previous study. In this study, NMDEA was demonstrated to attenuate depression-related behaviors in mice models of chronic unpredictable mild stress (CUMS), using a sucrose preference test, a forced swimming test, and a tail suspension test. However, the antidepressant mechanism of NMDEA appears to differ from that for AGO. Based on the analysis of fecal microbiota from mice, stress can alter the richness of the gut bacterial community, increasing the expression of immune-modulating microbiota, such as Clostridia, and decreasing the expression of probiotic bacteria, such as Lactobacillus. Treatment with NMDEA was able to recover the richness and to regulate the dysbiosis among bacterial species. Several studies have demonstrated that the gut microbiota population can induce inflammatory processes. To explore the effects of NMDEA on the suppression of pro-inflammatory factors, we used Western blotting to analyze the levels of interleukin 1 beta (IL-1β), interleukin 6 (IL-6), p65, and inducible nitric oxide synthase (iNOS). NMDEA suppressed the activation of IL-1β and IL-6, in the hippocampus, and IL-1β, IL-6, p65, and iNOS, in lipopolysaccharide (LPS)-induced BV-2 cells. These results suggested that NMDEA may affect the microbiota-inflammasome-brain axis, regulating relevant neuro-inflammatory markers and gut microbiota. Our data also suggested that using small molecules to modify the gut microbiota population or alter inflammasome signaling may represent a new therapeutic opportunity for the mitigation of depression.

Objectives. Disruption of microbial biofilms is an effective way to control dental caries. Drug resistance and side effects of the existing antimicrobials necessitate the development of novel antibacterial agents. The current study was aimed at investigating the antibacterial activities of the repurposed natural compound napabucasin against oral streptococci. Methods. The minimum inhibitory concentration, minimum bactericidal concentration, minimum biofilm inhibition concentration, and minimum biofilm reduction concentration of Streptococcus mutans, Streptococcus gordonii, and Streptococcus sanguinis were examined by a microdilution method. Cytotoxicity of napabucasin against human oral keratinocytes, human gingival epithelia, and macrophage RAW264.7 was evaluated by CCK8 assays. The dead/live bacterium and exopolysaccharide in the napabucasin-treated multispecies biofilms were evaluated by confocal laser scanning microscopy. Microbial composition within the napabucasin-treated biofilms was further visualized by fluorescent in situ hybridization and qPCR. And the cariogenicity of napabucasin-treated biofilms was evaluated by transverse microradiography. Results. Napabucasin exhibited good antimicrobial activity against oral streptococcal planktonic cultures and biofilms but with lessened cytotoxicity as compared to chlorhexidine. Napabucasin reduced the cariogenic S. mutans and increased the proportion of the commensal S. gordonii in the multispecies biofilms. More importantly, napabucasin significantly reduced the demineralization capability of biofilms on tooth enamels. Conclusion. Napabucasin shows lessened cytotoxicity and comparable antimicrobial effects to chlorhexidine. Repurposing napabucasin may represent a promising adjuvant for the management of dental caries.

Drug-resistant bacteria pose an increasingly serious threat to mankind all over the world. However, the currently available clinical treatments do not meet the urgent demand.Therefore, it is desirable to find new targets and inhibitors to overcome the problems of antibiotic resistance. Dihydrofolate reductase (DHFR) is an important enzyme required to maintain bacterial growth, and hence inhibitors of DHFR have been proven as effective agents for treating bacterial infections. This review provides insights into the recent discovery of antimicrobial agents targeting DHFR. In particular, three pathogens, Escherichia coli (E. coli), Mycobacterium tuberculosis(Mtb) and Staphylococcus aureus(S. aureus), and research strategies are emphasized. DHFR inhibitors are expected to be good alternatives to fight bacterial infections.

Purpose Lymph node metastasis (LNM) is a vital prognosis factor in patients with papillary thyroid microcarcinoma (PTMC). The study tried to identify clinicopathological factors for LNM of PTMC. Methods The clinicopathological data of 1031 patients with PTMC were extracted and analyzed. Univariate and multivariate analyses were used to identify risk factors associated with cervical lymph node metastasis. ROC analysis was used to determine the ideal critical points of the sum of the maximum diameter of multifocal in a unilateral lobe. Results The probability of LNM, central lymph node metastasis (CLNM) and lateral lymph node metastasis(LLNM)of PTMC patients were 35.6, 33.7 and 5.6%, respectively. In addition, 1.9% PTMC had LLNM only. Male, age ≤ 40 years, tumor largest diameter ≥ 5 mm, multifocal, non-uniform echoic distribution, the sum of the maximum diameter of multifocal in a unilateral lobe ≥ 8.5 mm, tumors in the lower pole location were prone to CLNM. Ultrasound mix-echo, the sum of the maximum diameter of the multifocal ≥ 10.75 mm, tumors in the upper pole location were extremely prone to LLNM. T3 were prone to LLNM or skip LLNM. Conclusions According to the clinicopathological characteristics of PTMC, the cervical lymph nodes should be correctly evaluated to guide the surgical treatment.

A series of (E)-3-(aryl(arylamino)methylene)indolin-2-one derivatives were synthesised using an efficient synthetic approach. The method involved reaction of 3-bromo-3-(bromo(aryl)methyl)indolin-2-one with substituted anilines through nucleophilic substitution and a simultaneous elimination using NaHCO3 in DMF. The anticancer activity of the products against four cell lines, HCT-116, A549, SKOV3 and MDA-MB-231, was also evaluated, and several compounds showed moderate inhibitory activity.

The RET tyrosine kinase is an important therapeutic target for medullary thyroid cancer (MTC), and drug resistance mutations of RET, particularly V804M and V804L, are a main challenge for the current targeted therapy of MTC based on RET inhibitors. In this investigation, we report the structural optimization and structure-activity relationship studies of N -phenyl-7,8-dihydro-6 H -pyrimido[5,4-b][1,4]oxazin-4-amine derivatives as a new class of RET inhibitors. Among all the obtained kinase inhibitors, 1-(5-( tert -butyl)isoxazol-3-yl)-3-(4-((6,7,8,9-tetrahydropyrimido[5,4-b][1,4]oxazepin-4-yl)amino)phenyl)urea ( 17d) is a multi-kinase inhibitor and potently inhibits RET and its drug resistance mutants. It showed IC 50 (half maximal inhibitory concentration) values of 0.010 μM, 0.015 μM, and 0.009 μM against RET-wild-type, RET-V804M, and RET-V804L, respectively. 17d displayed significant anti-viability potencies against various RET-driving tumor cell lines. In a xenograft mouse model of NIH3T3-RET-C634Y, 17d exhibited potent in vivo anti-tumor activity, and no obvious toxicity was observed. Mechanisms of action were also investigated by Western blot and immunohistochemical assays. Collectively, 17d could be a promising agent for the treatment of MTC, hence deserving a further investigation.

Antibiotic-resistance by bacteria is a growing global concern within the healthcare field, and it has provided an impetus for continued antimicrobial development. Pyrinezolid (PZ), a novel oxazolidinone compound, can effectively inhibit most gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE). Though PZ is a promising antimicrobial candidate, the druggability of PZ is limited by its poor water solubility. Therefore, the amphipathic mPEG-PLLA copolymer was used to prepare the pyrinezolid micelles (PZ-M). Herein, we described the preparation, pharmacokinetic properties, tissue distribution, efficacy and toxicity of PZ-M. In vivo studies show that PZ-M possess prolonged blood circulation time and increased oral bioavailability compared with free PZ. Meanwhile, PZ-M increase lung PZ exposure and reduce liver and kidney exposure, which indicates that PZ-M may enhance the efficacy in vivo in MRSA-related pneumonia patients and decrease potential renal and hepatic toxicities.

Chromosome region maintenance 1 (CRM1) exports nuclear export signal (NES) containing cargos from nucleus to cytoplasm and plays critical roles in cancer and viral infections. Biochemical and biophysical studies on this protein were often obstructed by its low purification yield and stability. With the help of PROSS server and NES protection strategy, we successfully designed three small fragments of CRM1, each made of four HEAT repeats and capable of binding to NESs in the absence of RanGTP. One of the fragments, C7, showed dramatically improved purification yield, thermostability, mechanostability, and resistance to protease digestion. We showed by isothermal titration that the protein kinase inhibitor NES binds to C7 at 1.18 μM affinity. Direct binding to C7 by several reported CRM1 inhibitors derived from plants were verified using pull-down assays. These fragments might be useful for the development of CRM1 inhibitors towards treatment of related diseases. The strategy applied here might help to tackle similar problems encountered in different fields.

Unlike other bacterial ClpP systems, mycobacterial ClpP1P2 complex is essential for mycobacterial survival. The functional details of Mycobacterium tuberculosis (Mtb) ClpP1P2 remains largely elusive and selectively targeting ClpP of different species is a big challenge. In this work, cediranib was demonstrated to significantly decrease the activity of MtbClpP1P2. By solving the crystal structure of cediranib-bound MtbClpP1P2, we found that cediranib dysregulates MtbClpP1P2 by interfering with handle domain of the equatorial region of MtbClpP1, indicating that the inter-ring dynamics are crucial for its function. This finding provides direct evidence for the notion that a conformational switch in the equatorial handle domain is essential for ClpP activity. We also present biochemical data to interpret the distinct interaction pattern and inhibitory properties of cediranib toward MtbClpP1P2. These results suggest that the variable handle domain region is responsible for the species-selectivity of cediranib, which suggests the equatorial handle domain as a potential region for screening pathogen-specific ClpP inhibitors.

Tuberculosis is the contagious disease responsible for the highest number of deaths worldwide. Here, we screened a commercially available compound library and found napabucasin to possess a moderate anti-tubercular activity against M. tuberculosis H37Ra (MIC 2.5 μg mL(–1), 10.4 μM). Three series of napabucasin derivatives were further evaluated for their in vitro anti-tubercular activities against Mtb H37Ra. The activity of most derivatives was either retained or enhanced compared with that of napabucasin. Compound 3s was the most active compound showing a MIC value of 0.3125 μg mL(–1) (0.9 μM). Furthermore, several compounds were selected and evaluated against the Mtb H37Rv standard strain and six Mtb clinical isolates. Importantly, these compounds were found to be effective against Mtb clinical isolates with multi-resistance to isoniazid, rifampicin, and ethambutol.

Human caseinolytic protease proteolytic subunit (HsClpP) is a highly conserved serine protease that plays an essential role in cell homeostasis through removal of the damaged and/or misfolded proteins. Recently, due to its critical role in cancer proliferation and metastasis, HsClpP has been considered as a promising target for the cancer treatment. In this paper, through a random screening toward a library of 2086 bioactive chemicals, a novel compound I, 3-(3,5-dibromo-4-hydroxybenzylidene) -5-iodoindolin-2-one, was identified as a potent suppressor of HsClpP. Herein, a series of compound I derivatives were synthesized, and evaluated for their anti-cancer activities on a variety of cancers cells. Through the preliminary biological assay in vitro, including MTT assay and proteolytic activity assay, compound I was identified as the most potent inhibitor. Treatment with compound I impaired the migration of Hela cells. In addition, compound I disrupted the mitochondrial function, and reduced the level of the SDHB and induced the production of the ATF4. In general, compound I is a promising probe of HsClpP for cancer treatment, and is a good lead compound for the development of novel anti-cancer agent.

Antibiotics have been a key part of clinical treatments for more than 70 years. Long-term use of antimicrobial treatments has led to the development of severe bacterial resistance, which has become increasingly serious due to antibiotic abuse, resulting in the treatment of bacterial infections becoming challenging. The repurposing of approved drugs presents a promising strategy to address current bottlenecks in the development of novel antibacterial agents. Drug repurposing is a cost-effective emerging strategy, which aims to treat resistant infectious diseases by identifying known drugs with predicted efficacy for diseases other than the target disease. This strategy has potential in the treatment of tuberculosis (TB), particularly drug-resistant TB. In recent years, a panel of drugs approved for clinical use or clinical trials, such as linezolid, vancomycin and celecoxib, have been found to have anti-TB activities. However, the utility of drug repurposing is limited by the number of candidate compounds and their low activities. The low activities of repurposed drugs have slowed the development of a drug-repurposing strategy for anti-TB drugs. The present review discusses progress in the discovery of new anti-TB agents through drug repurposing since 2014. We also discuss the challenges faced and analyze the innovative ways that are being used to overcome these difficulties. This review may provide a useful guide for researchers in the field of drug repurposing.

With antibiotics resistance developing rapidly, new antibacterial agents are needed to be discovered. We readily synthesized 11 indolin-2-one compounds and found a hybrid of indolin-2-one and nitroimidazole 3-((1-methyl-5-nitro-1H-imidazol-2-yl)methylene)indolin-2-one to be effective on Staphylococcus aureus strains. Six derivatives of this compound were further designed and synthesized in order to enhance its efficacy. After a second turn of structural refinement, a novel hybrid of indolin-2-one and nitroimidazole 3-((1-methyl-5-nitro-1H-imidazol-2-yl)methylene)-5-nitroindolin-2-one with a nitro group on C-5 position of indolin-2-one was shown to exhibit remarkable antibacterial activities with a low MIC value against MRSA ATCC 33591. Besides, this molecule demonstrated its potency on Gram-negative bacteria and VRE strain. The time-killing curve experiment showed its good bactericidal activity. Low hemolytic rate suggested its promising safety profile.

FYL-66 and its hydrochloride FYL-67 have been identified as new chemical entities (NCE) with pronounced in vitro and in vivo activities against MRSA and MSSA. Aiming to explore the structure–activity relationship at the C-5 side chain of FYL-66 and find novel potential antibacterial agents, a series of analogues were designed and synthesized by the introduction of various substituents at the C-5 position of the oxazolidinone ring. Their in vitro antibacterial activities were also evaluated by the microdilution method. Novel compounds 31, 33, 37, 39 and 40 demonstrated potent antibacterial activities with MIC values in the range of 2–4 μg mL−1. Difluoro-substituted analogue 40 was found to possess a good balance between antibacterial efficacy, physicochemical properties and safety profile. In a murine systemic infection model, analogue 40 showed comparable protection rates with FYL-66. The absolute bioavailability of 40 was 89.6% with half-lives of 8.87 ± 3.25 h (p.o.) and 5.40 ± 1.40 h (i.v.), respectively. Meanwhile, our findings show the importance of the C-5 side chain of FYL-66 and imply compounds with small C-5 substituents mimicking the acetamide group display better activities. It is also quite intriguing that different antibacterial effects are presented by analogues of FYL-66, Linezolid and other oxazolidinones with the same fluoro-substitution patterns of the acetyl group at the C-5 position.

OBJECTIVES Infections of hospitalized patients caused by biofilms formed by Staphylococcus aureus represent a major problem. Using in vitro and in vivo biofilm models, we evaluated the efficacy of the novel oxazolidinone FYL-67, by using linezolid (the only clinically approved oxazolidinone antibiotic) as a control, for inhibiting S. aureus biofilm formation. METHODS Antibiofilm activity was determined using strains of methicillin-susceptible S. aureus and methicillin-resistant S. aureus. We studied the mechanism(s) and pharmacodynamics of antibiofilm activity as follows: (i) effects of pre- and post-exposure to FYL-67 or linezolid on biofilm formation; (ii) the effect of FYL-67 on biofilm structure; (iii) the role of FYL-67 in biofilm composition; (iv) effects on cell morphology; and (v) efficacy of FYL-67 and linezolid using an in vivo murine model of catheter infection. RESULTS FYL-67 effectively inhibited biofilm formation using in vitro and in vivo assays. CONCLUSIONS Our data suggest that oxazolidinone compounds, such as FYL-67, may serve as antibiofilm agents.

In this study, a series of novel naphthalene compounds were synthesized and screened for their antidepressant-like activities in vitro and in vivo. Their values for two descriptors (ClogP, tPSA) of the blood-brain barrier (BBB) were calculated for early assessment of the central nervous system (CNS) drug-likeness. Seven of them (6d, 6i, 6k, 6o, 6p, 6s and 6t) demonstrated potential protective effects on corticosterone-induced lesion of PC12 cells although they cannot repair the irreversible oxidant injury to PC12 cells by hydrogen peroxide. Compounds with promising neurorestorative activities (6k, 6o and 6p) were further evaluated for their in vivo effects by forced swim test (FST) and open field test (OFT) in C57 mice models. The FST results showed that compounds 6k, 6o and 6p remarkably reduced the immobility time of the tested mice. Among them, compound 6k was the most potent one, much more effective than Agomelatine and comparable to Fluoxetine. The OFT results showed that mice treated with compound 6k traveled a longer distance than those treated with Agomelatine or Fluoxetine, indicating a better general locomotor activity. The paper also proposed a possible binding mode of compound 6k with glucocorticoid receptor by docking study. The in vitro cytotoxicity data on HEK293 and L02 cells suggested compound 6k to be a promising antidepressant candidate for subsequent investigation.

Small molecules with oxathiazol-2-one moiety were recently reported as potent inhibitors of Mycobacterium bovis var. bacilli Calmette–Guerin (BCG), among which HT1171 was the most potent and selective proteasome inhibitor. Herein we synthesized a series of novel compounds by bioisosteric replacement of the oxathiazol-2-one ring with 3H-1,2,4-dithiazol-3-one, and also fifteen 1,3,4-oxathiazol-2-one molecules in order for potency comparison and structure–activity relationship elucidation since their antibacterial effects on the virulent strains were not evaluated before. All the compounds were assessed for antitubercular activities on the virulent H37Rv strain by a serial dilution method. Among the tested compounds, 3H-1,2,4-dithiazol-3-one compound 4n was found to be the most active with a lowest MIC90 value of 1 μg/mL. Furthermore, the cytotoxicities of all the compounds against normal human liver cell line L02 were determined by an MTT method. Compound 4n displayed a lower inhibitory ratio than HT1171 at the concentration of 100 μM, indicating its better safety profile.

In this work, a novel oxazolidinone compound FYL-67 was synthesized, and the obtained FYL-67 could form nanoassemblies in aqueous solution by a self-assembly method without using any carrier, organic solvent, or surfactant. The prepared FYL-67 nanoassemblies had a particle size of 264.6 ± 4.3 nm. The FYL-67 nanoassemblies can be lyophilized into a powder form without any cryoprotector or excipient, and the re-dissolved FYL-67 nanoassemblies are stable and homogeneous. The in vitro release profile showed a significant difference between rapid release of free FYL-67 and much slower and sustained release of FYL-67 nanoassemblies. In vitro susceptibility tests were conducted in three strains of methicillin-susceptible Staphylococcus aureus (MSSA) and three strains of methicillin-resistant Staphylococcus aureus (MRSA), using linezolid as a positive control. FYL-67 nanoassemblies exhibited excellent in vitro activity, with a minimum inhibitory concentration (MIC) value of 0.5 μg mL(-1) against MRSA. In the in vitro post-antibiotic effect (PAE) evaluation, FYL-67 nanoassemblies showed a more powerful effect than linezolid. Besides, in vitro cytotoxicity tests indicated that FYL-67 nanoassemblies had a very low cytotoxicity on HEK293 cells and L02 cells. Furthermore, in both MSSA and MRSA systemic infection mouse models, FYL-67 nanoassemblies showed a lower ED(50) than linezolid. In a murine model of MRSA systemic infection, FYL-67 nanoassemblies displayed an ED(50) of less than 4.0 mg kg(-1), which is 2.3-fold better than that of linezolid. Our findings suggested that the FYL-67 nanoassemblies may be a potential drug candidate in MRSA therapy.

A series of 4-(1 H-indol-3-yl-methylene)-1 H-pyrazol-5(4 H)-one derivatives have been synthesised. The Z structure of 4-[(1-methyl-1 H-indol-3-yl)methylene]-3-phenyl-1 -p-tolyl-1 H-pyrazol-5-one was determined by X-ray crystallography. The antitumour activity was evaluated against five cancer cells by MTT assay. [(1 H-Indol-3-yl)methylene]-1-(2,4-dini-trophenyl)-3-methyl-1 H-pyrazole-5-one and 4-{4-[(1-benzyl-1 H-indol-3-yl)methylene]-3-methyl-5-oxo-4,5-dihydro-1 H-pyrazol-1-yl}-benzoic acid have similar anticancer activity with 5-UF on the test cancer cells (exception of A375). Almost all the target compounds displayed antitumour activity against A549 and PC-9, and those with benzyl at 1-position of indole had higher activity against PC-9 (IC50 value lower than 30 μM). Those with benzyl at the indole and carboxyl at the phenyl part of of pyrazole were more active against PC-9 and A549 cells, providing a good indication for subsequent optimisation as lung cancer inhibitory agents.

A scaffold-hopping strategy toward Agomelatine based on in silico screening and knowledge analysis was employed to design novel antidepressant agents. A series of 3, 4-dihydroisoquinoline compounds were selected for chemical synthesis and biological assessment. Three compounds (6a-1, 6a-2, 6a-9) demonstrated protective effects on corticosterone-induced lesion of PC12 cells. Compound 6a-1 also displayed low inhibitory effects on the growth of HEK293 and L02 normal cells and it was further evaluated for its potential antidepressant effects in vivo. The forced swim test (FST) results revealed that compound 6a-1 remarkably reduced the immobility time of rats and the open field test (OFT) results indicated a better general locomotor activity of the rats treated with compound 6a-1 than those with Agomelatine or Fluoxetine. Mechanism studies implied that compound 6a-1 can significantly reduce PC12 cell apoptosis by up-regulation of GSH and down-regulation of ROS in corticosterone-induced lesion of PC12 cells. Meanwhile, the down-regulation of calcium ion concentration and up-regulation of BDNF level in PC12 cells may account for the neuroprotective effects. Furthermore, compound 6a-1 can increase cell survival and cell proliferation, promote cell maturation in the rat hippocampus after chronic treatment. The acute toxicity data in vivo indicated compound 6a-1 exhibited less hepatotoxicity than Agomelatine.

Results from previous studies on the association between methylenetetrahydrofolate reductase (MTHFR) polymorphisms C677T and A1298C and lung cancer have been conflicting. The aim of this meta-analysis was to clarify the effect of MTHFR polymorphisms on the risk of lung cancer. An electronic search of PubMed, EMBASE, the Cochrane library, and the China Knowledge Resource Integrated Database for papers on C677T and A1298C and susceptibility to lung cancer was performed. The STATA software (Version 13.0) was used for statistical analysis. Statistical heterogeneity, tests of publication bias, and a sensitivity analysis were performed. Twenty-six studies on C677T (12,324 cases and 12,532 controls) and thirteen studies on A1298C (6773 cases and 8207 controls) were included in the meta-analysis. The MTHFR C677T polymorphism showed significant pooled ORs for the homozygote comparison (TT versus CC: OR = 1.518, 95%CI = 1.220-1.890), heterozygote comparison (CT versus CC: OR = 1.053, 95%CI = 0.940-1.179), dominant model (CT + TT versus CC: OR = 1.143, 95%CI = 1.013-1.291), recessive model (TT versus CT + CC: OR = 1.435, 95%CI = 1.190-1.730), and additive model (T versus C: OR = 1.176, 95%CI = 1.066-1.298). In summary, our meta-analysis showed that the MTHFR C677T polymorphism is associated with a significant increase in lung cancer risk in Asian and overall populations, but not in Caucasian populations. However, no significant association between the MTHFR A1298C polymorphism and lung cancer risk was found in either the Caucasian or Asian group with any genetic models.

Published studies on the association between the C677T and A1298C polymorphisms of the methylenetetrahydrofolate reductase (MTHFR) gene and male infertility risk are controversial. To obtain a more precise evaluation, we performed a meta-analysis based on published case-control studies. We conducted an electronic search of PubMed, EMBASE, the Cochrane Library, the Web of Science, and the China Knowledge Resource Integrated Database for papers on MTHFR gene C677T and A1298C polymorphisms and male infertility risk. Pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) were used to assess the strength of association in homozygote, heterozygote, dominant, recessive, and additive models. Statistical heterogeneity, test of publication bias, and sensitivity analysis were carried out using the STATA software (Version 13.0). Overall, 21 studies of C677T (4505 cases and 4024 controls) and 13 studies of A1298C (2785 cases and 3094 controls) were included in this meta-analysis. For C677T, the homozygote comparison results were OR = 1.629, 95%CI (1.215- 2.184), and the recessive model results were OR = 1.462 (1.155- 1.850). For A1298C, the homozygote comparison results were OR = 1.289 (1.029-1.616), and the recessive model results were OR = 1.288 (1.034-1.604). In conclusion, the current meta-analysis showed that the MTHFR C677T polymorphism was associated with a significantly increased male infertility risk in the Asian and overall populations, but not in the Caucasian population, and there was a significant association between the A1298C polymorphism and male infertility risk in the Asian, Caucasian, and overall groups.

Background and Aim: (Z)2-(5-(4-methoxybenzylidene)-2, 4-dioxothiazolidin-3-yl) acetic acid (MDA) is an aldose reductase (AR) inhibitor. Recent studies suggest that AR contributes to the pathogenesis of inflammation by affecting the nuclear factor κB (NF-κB)-dependent expression of cytokines and chemokines and therefore could be a novel therapeutic target for inflammatory pathology. The current study evaluated the in vivo role of MDA in protecting the liver against injury and fibrogenesis caused by CCl4 in rats, and the underlying mechanisms. Methods: A single injection of CCl4 induced acute hepatitis, and repeated injections were used to induce hepatic fibrosis in rats. Therapeutic efficacy was assessed by comparison of the severity of hepatic injury and fibrosis in MDA-treated rats versus untreated controls. Results: MDA significantly protected the liver from injury by reducing the activity of serum alanine aminotransferase, and improving the histological architecture of the liver. MDA modulated NF-κB-dependent activation of inflammatory cytokines by reducing hepatic mRNA levels of tumor necrosis factor-α, interleukin-1β, inducible nitric oxide (NO) synthase and transforming growth factor-β. In addition, MDA attenuated oxidative stress by increasing the content of hepatic glutathione. These favorable changes were associated with suppressed hepatic NF-κB activation by MDA. MDA treatment improved liver fibrosis in rats that received repeated CCl4 injections. In vitro, MDA attenuated phosphorylation of IκB and activation of NF-κB, and thus prevented biosynthesis of NO in lipopolysaccharide-activated RAW264.7 cells. Conclusions: The present study suggests that AR is a novel therapeutic anti-inflammatory target for the treatment of hepatitis and liver fibrosis.

A series of compounds with a diphenyl ether nucleus were synthesized by incorporating various amines into the diphenyl ether scaffold with an amide bond. Their antitubercular activities were evaluated against Mycobacterium tuberculosis H(37)Rv by a microdilution method, with MIC values ranging from 4 to 64μg/mL. Through structure-activity relationship studies, the two chlorine atoms at 3 and 4 positions in the phenyl ring of R(2) group were found to play a significant role in the antitubercular activity. The most potent compound 6c showed an MIC value of 4μg/mL and a good safety profile in HepG2 cell line by the MTT assay. Compound 6c was further found to be effective in a murine model of BCG infection, providing a good lead for subsequent optimization.

Idiopathic pulmonary fibrosis is regarded as a lethal chronic disease accompanied with excessive collagen disposition. In the early stage, monocyte chemotactic protein-1 (MCP-1) plays a crucial role in the process. Our previously screening with a vitro assay through inhibition of chemotaxis of RAW264.7 cells stimulated by MCP-1 proved that several analogues of thiazolidinediones, especially (Z)-5-(4-methoxybenzylidene)thiazolidine-2,4-dione (SKLB010), had potency of protecting acute liver injury in vivo without obvious toxicity. The present study aimed to investigate the preventive effect of SKLB010 in bleomycin-induced pulmonary fibrosis and further explore the underlying mechanisms. Bleomycin (BLM) was injected intratracheally at a single dose of 5 U kg(-1) for pulmonary fibrosis induction. SKLB010 (25, 50 mg/kg/d) was respectively administrated by gavages 1 d prior to BLM administration and continued to the end of the study (for 4 weeks). Our results demonstrated that SKLB010 diminished the increase of macrophage, neutrophil and lymphocyte counts as well as the levels of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 in bronchoalveolar lavage fluid on day 14 (p0.05). Moreover, oral gavages of SKLB010 also ameliorated histological changes and significantly suppressed collagen deposition on day 28. The treatment with SKLB010 exerted approximately 34.6% the hydroxyproline content reduction for 25 mg/kg dose and 56.7% reduction for 50 mg/kg dose in contrast to bleomycin-induced group (p0.05). Meanwhile, SKLB010 inhibited the overexpression of tumor growth factor (TGF)-β1 and Smad3 in a dose-dependent manner. In conclusion, our results showed that SKLB010 could attenuate the BLM-induced pulmonary fibrosis in vivo and therefore be a promising anti-fibrogenic candidate.

In our previous study, we have demonstrated that (Z)-5-(4-methoxybenzylidene) thiazolidine-2, 4-dione (SKLB010), a novel analogue of thiazolidinediones, showed protection against concanavalin A (Con A)-induced hepatitis via inhibiting the migration of macrophages and the expression of pro-inflammatory mediators. In present study, Transwell assay was applied to study the effects of SKLB010 on macrophage-like Raw264.7 cell migration and we investigated the effects of SKLB010 on NO generation in vitro. We also studied in vivo effects of SKLB010 on adjuvant-induced arthritis in Lewis rats by oral administration. It was proved that SKLB010 depressed cells migration and the production of NO in Raw264.7 cells in a dose-dependent way. Our results also indicated that oral administration of 50 mg/kg SKLB010 markedly resulted in a clear suppression of clinical signs compared to untreated groups, showing as markedly reduction of paw swelling and inhibition of body weight decreasing. The improvement in disease severity was accompanied by suppression of CD68-positive cells in knee joint and by inhibition of production in pro-inflammatory cytokines of TNF-α, IL-1β and IL-6 in serum. The elevated TNF-α, IL-1β and iNOS mRNA expression in tissue were down-regulated after treatment with SKLB010. SKLB010 also significantly inhibited the histological progress of RA. These data indicate that SKLB010 is a potent anti-inflammatory therapeutic agent targeting the inflammatory response of macrophages.

Two series of 3-aminopyrazole compounds including 24 1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazoles and 16 pyrazolo[3,4-b]pyridines were synthesized and evaluated against HCT116, A549, and A2780 tumor cell lines. Among them, three compounds were found to have the ideal anti-proliferative activities in vitro. Docking experiments showed that the novel pyrazolo[3,4-b]pyridines share the similar interaction mode with Aurora-A kinase as PHA739358.

Phosphoinositide 3-kinase-gamma (PI3Kgamma) has been identified to play the critical roles in inflammatory cells activation and recruitment in multiply inflammatory diseases and it promised to be a prospective target for relevant inflammatory diseases therapy. AS605240, a selective PI3Kgamma inhibitor, has been proved effective on several inflammatory diseases. In this study, we investigated the protective effect of AS605240 on bleomycin-induced pulmonary fibrosis in rats. Our results showed that orally administration of AS605240 significantly prevented lung inflammation and reduced collagen deposition. AS605240 also inhibited augmented expression of TNF-alpha and IL-1beta induced by bleomycin instillation. Moreover, the mRNA levels of TNF-alpha and IL-1beta in lung were remarkably suppressed. Histological assessment found that AS605240 reduced the expression of TGF-beta(1) and prevented T lymphocytes infiltration to lung. Phospho-Akt level in inflammatory cells by blocking PI3Kgamma was down-regulated and the inhibition of Akt phosphorylation was further confirmed by Western blot. Our findings illustrated that AS605240 was effective for preventing pulmonary fibrosis by suppressing inflammatory cells recruitment and production of inflammatory cytokines. These findings also suggest that PI3Kgamma may be a useful target in treating inflammation diseases and AS605240 may represent a promising novel agent for the future therapy of pulmonary fibrosis.

A large amount of evidence suggests that monocytes/macrophages infiltration is implicated in a variety of inflammatory diseases including acute liver injury. Monocyte chemoattractant protein 1 (MCP-1) plays a crucial role in the process of macrophages recruitment. We herein presented a small-molecule library and a feasible quick screening method of evaluating potency of inhibition of chemotaxis of RAW264.7 cells stimulated by MCP-1. Fifty-three small molecules were synthesized and screened, and four compounds (2g, 2h, 4f, and 6h) showed inhibitory effects with IC(50) values range from 0.72 to 20.47 microM, with compound 4f being the most efficient. Further in vivo studies demonstrated that oral administration of 2g, 2h, 4f, or 6h decreases, most significantly for 4f, the serum levels of alanine aminotransaminase (ALT) and asparate aminotransaminase (AST) in ConA-induced acute livery injury BALB/c mice. Histopathological evaluation liver sections confirmed 4f as a potent, orally active compound for hepatoprotective effects against ConA-induced acute liver injury in BALB/c mice.

The protease β-secretase plays a critical role in the synthesis of pathogenic amyloid-β in Alzheimer's disease. In this study, pharmacophore constructed from receptor-ligand complex was used to screen Chemdiv and Zinc database and the resulting hits were subjected to docking experiments using LiandFit and CDOCKER programs. Molecules with high consensus scores and good interaction patterns in docking programs were retained. Drug-likeness assay including Lipinski's rule of five and ADMET properties filters were further used to identify BACE1 inhibitor. Finally, 13 compounds with novel scaffolds were selected and, considering of the nature of relative high LogP value of many marketed AD drugs, three of them with top 3 predicted LogP value were evaluated for their IC50 values in vitro by BACE1 enzymatic activity study. We believe that compound 13 with an IC50 value of 136 µM can be a lead compound with great potential in BACE1 inhibition and increasing activity by subsequently structure modification or optimization. At the same time, we found that the interaction between the residues Asp228, Asp32 of BACE1 and ligands is significant through analyzing the binding mode of 13 candidate compounds.

Ibuprofen is the first line of treatment for osteoarthritis and arthritis. The main side effects of ibuprofen especially in long-term treatment include gastric ulcer, duodenal ulcer and indigestion etc. Therefore, screening drugs with effective gastric protective effects and low toxicity for combination therapy with ibuprofen is necessary. The mechanism of gastric damage induced by ibuprofen is still unclear, however, cell damage caused by reactive oxygen species (ROS) is considered as the main reason. Preliminary screening of literature with the criteria of low toxicity led to four histamine-2 receptor antagonists (H2RAs): nizatidine, famotidine, lafutidine, and roxatidine acetate, which were selected for further investigation. These drugs were evaluated systemically by examining the gastric ulcer index, lipid peroxidation (LPO), membrane permeability, toxicity to main organs, and the influence on the activity of antioxidant enzymes, and myeloperoxidase (MPO). Nizatidine was found to be the best gastric protective agent. It exhibited excellent protective effect by increasing antioxidant enzyme activity, decreasing MPO activity, reducing LPO, and membrane permeability. Combination treatment with nizatidine and ibuprofen did not show any significant toxicity. Nizatidine was considered as a good option for combination therapy with ibuprofen especially for diseases that require long-term treatment such as arthritis and osteoarthritis.

The protein kinase inhibitor 7-hydroxystaurosporine (UCN-01) is one of the most potent and frequently used proapoptotic stimuli. The BH3-only molecule of Bcl-2 family proteins has been reported to contribute to UCN-01-induced apoptosis. Here we have found that UCN-01 triggers Puma-induced mitochondrial apoptosis pathway. Our data confirmed that Akt-FoxO3a pathway mediated Puma activation. Importantly, we elucidate the detailed mechanisms of Puma-induced apoptosis. Our data have also demonstrated that caspase-9 is a decisive molecule of Puma induction after UCN-01 treatment. Caspase-9 mediates apoptosis through two kinds of feedback loops. On the one hand, caspase-9 enhances Puma activation by cleaving Bcl-2 and Bcl-xL independent of caspase-3. On the other hand, caspase-9 directly activated caspase-3 in the presence of caspase-3. Caspase-3 could cleave XIAP in an another positive feedback loop to further sensitize cancer cells to UCN-01-induced apoptosis. Therefore, caspase-9 mediates Puma activation to determine the threshold for overcoming chemoresistance in cancer cells.

Micro- and nanoparticle formulations are widely used to improve the bioavailability of low solubility drugs. In this study, biodegradable poly(L-lactide acid)-Pluronic L121-poly(L-lactide acid) (PLLA-L121-PLLA) was developed. And then a controlled drug delivery system (CDDS), docetaxel (DOC) loaded PLLA-L121-PLLA porous microsphere (DOC MS) was prepared for colorectal peritoneal carcinomatosis (CRPC) therapy. DOC MS was prepared by DOC and PLLA-L121-PLLA using an oil-in-water emulsion solvent evaporation method. The particle size, morphological characteristics, encapsulation efficiency, in vitro drug release studies and in vitro cytotoxicity of DOC MS have been investigated. In vitro release profile demonstrated a significant difference between rapid release of free DOC and much slower and sustained release of DOC MS. Furthermore, cytotoxicity assay indicated cytotoxicity was increased after DOC was encapsulated into polymeric microspheres. In addition, intraperitoneal administration of DOC MS could effectively suppress growth and metastasis of CT26 peritoneal carcinomatosis in vivo, and prolonged the survival of tumor bearing mice. Immunohistochemistry staining of tumor tissues with Ki-67 revealed that DOC MS induced a stronger anti-tumor effect by increasing apoptosis of tumor cells in contrast to other groups (P

A variety of new mono-oxazolidinone molecules by modifying the C-ring of Linezolid, a marketed antibiotic for MRSA, were synthesized and tested for their in vitro antibacterial activities against several Staphylococcus aureus , Mycobacterium smegmatis and two Gram-negative bacteria strains ( Escherichia coli and Pseudomonas aeruginosa ). Among them, compounds 4 – 7 displayed moderate antimicrobial activities. After development of a second oxazolidinone ring in the western part of the mono-oxazolidinone compounds 4 – 7 by a ring closure reaction with N , N′ -carbonyldiimidazole (CDI), we found thus obtained bis-oxazolidinone compounds 22 – 25 possess excellently inhibitory activities against H 37 Rv but poor or no effects on other test bacteria. Among them, bis-oxazolidinone compound 22 and 24 are the most potent two compounds with a same MIC value of 0.125 μg/mL against H 37 Rv virulent strain. Compound 22 also exhibited extremely low cytotoxicity on monkey kidney Vero cells with a selective index (IC 50 /MIC) over 40,000, which suggested bis-oxazolidinone compound 22 is a promising lead compound for subsequent investigation in search of new antitubercular agents.

In this work, nineteen analogues of Agomelatine were readily synthesized through structural modification of the acetamide side-chain starting from the key common intermediate 2-(7-methoxynaphthalen-1-yl) ethanamine (3), which was prepared from commercially available compound 2-(7-methoxynaphthalen-1-yl) acetonitrile (2) in two steps. Corticosterone-induced PC12 pheochromocytoma cells phenotypic in vitro model was utilized to evaluate their potential antidepression activities. Imide compound 4a and acylamino carboxylic acid analogue 5b showed good protective effects on traumatic PC12 cells with protection rates of 34.2% and 23.2%, respectively. Further in vivo assessments in C57 mice FST (forced swim test) model demonstrated that compound 4a significantly reduced the immobility time of the tested subjects, indicating antidepressant-like activity. Preliminary toxicity assays conducted on human normal liver L02 cells and embryonic kidney 293 cells suggested a relatively low safety risk for compound 4a compared with the marketed drugs Agomelatine and Fluoxetine. The promising antidepressant-like efficacy of compound 4a, together with the relatively low toxicity to the normal tested cells and high liability of diffusion through the blood-brain barrier (BBB), presents us insights of exploration of me-better drug candidates of Agomelatine.

Several 4-[indol-3-yl-methylene]-1H-pyrazol-5(4H)-one derivatives (V) (32 examples) are synthesized via an Aldol condensation reaction.