Search

Diarylureas are widely used in self-assembly and supramolecular chemistry owing to their outstanding characteristics as both H-bond donors and acceptors. Unfortunately, this bonding property is rarely applied in the development of urea-containing drugs. Herein, seven related dimethyl sulfoxide (DMSO) complexes were screened from 12 substrates involving sorafenib and regorafenib, mainly considering the substitution effect following a robust procedure. All complexes were structurally confirmed by spectroscopic means and thermal analysis. Specially, five cocrystals with three deuterated, named sorafenib·DMSO, donafenib·DMSO, deuregorafenib·DMSO, 6·DMSO, and 7·DMSO were obtained. The crystal structures revealed that all host molecules consistently bonded with DMSO in intermolecular interaction in a 1:1 stoichiometry. However, further comparison with documented DMSO complexes and parent motifs presented some arrangement diversities especially for 6·DMSO which offered a counter-example to previous rules. Major changes in the orientation of meta-substituents and the packing stability for sorafenib·DMSO and deuregorafenib·DMSO were rationalized by theory analysis and computational energy calculation. Cumulative data implied that the planarization of two aryl planes in diarylureas may play a crucial role in cocrystallization. Also, a polymorph study bridged the transformation between these ureas and their DMSO complexes.

Human dihydroorotate dehydrogenase (hDHODH) is an attractive target for cancer therapy. Based on its crystal structure, we designed and synthesized a focused compound library containing the structu...

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.

A novel scalable four-step process has been developed to improve the synthesis of obeticholic acid (OCA). The key step of this process was the isolation of the amide intermediate, which underwent hydrogenation, basic epimerization, ketone reduction, and amide hydrolysis in a one-pot procedure. The use of efficient single recrystallization for the final purification in this process made the corresponding work-up procedure more concise and environmentally friendly. A kilogram-scale production of OCA following this process could achieve over 70% yield with all impurities controlled below 0.10%.

Human dihydroorotate dehydrogenase (DHODH), the enzyme that catalyzes the rate‐limiting step in de novo pyrimidine biosynthesis, is considered to be an attractive target for potential treatment of autoimmune disease and cancer. Here, we present a novel class of human DHODH inhibitors with high inhibitory potency. The high‐resolution crystal structures of human DHODH complexed with various agents reveal the details of their interactions. Comparisons with the binding modes of teriflunomide and brequinar provide insights that may facilitate the development of new inhibitors targeting human DHODH.

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.

Serine, the source of the one-carbon units essential for de novo purine and deoxythymidine synthesis plays a crucial role in the growth of cancer cells. Phosphoglycerate dehydrogenase (PHGDH) which catalyzes the first, rate-limiting step in de novo serine biosynthesis has become a promising target for the cancer treatment. Here we identified H-G6 as a potential PHGDH inhibitor from the screening of an in-house small molecule library based on the enzymatic assay. We adopted activity-directed combinatorial chemical synthesis strategy to optimize this hit compound. Compound b36 was found to be the noncompetitive and the most promising one with IC50 values of 5.96 ± 0.61 μM against PHGDH. Compound b36 inhibited the proliferation of human breast cancer and ovarian cancer cells, reduced intracellular serine synthesis, damaged DNA synthesis, and induced cell cycle arrest. Collectively, our results suggest that b36 is a novel PHGDH inhibitor, which could be a promising modulator to reprogram the serine synthesis pathway and might be a potential anticancer lead worth further exploration.

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.

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.

A series of 1 H-thieno[2,3-c]chromen-4(2 H)-one derivatives were synthesised through Knoevenagel condensation of substituted flavanones with thiazolidine-2,4-dione in ethanol in the presence of piperidine. The mechanism of the reaction was proposed. All synthesised compounds were characterised by IR, 1H NMR, 13C NMR, HRMS, and elemental analysis. The structure of 2-(3-chlorophenyl)-1 H-thieno[2,3- c]chromen-4(2 H)-one was confirmed by a single crystal X-ray diffraction analysis. A preliminary antitumour screening showed that 2-(2-fluorophenyl)-1 H-thieno [2,3- c]chromen-4(2 H)-one had moderate to good activity against A549, BGC-823, HCT116 and MDA-MB-453 cancer cell lines, and 2-(3,4-dimethoxyphenyl)-1 H-thieno[2,3- c]chromen-4(2 H)-one displayed similar activity against these four kinds of cancer cells compared with the reference drug.

In the current study, we used an integrated approach combining bioinformatics, rational drug design, one-pot synthesis, and biological experiments in vitro for the potential discovery of novel tryptophanyl-tRNA synthetase (TrpRS) inhibitors. Atom economic and diastereoselective syntheses were used to generate several Spirooxindole–indenoquinoxaline derivatives in situ from isatin and amino acids viz. proline, phenylglycine, and sarcosine through targeting the 1,3-dipolar cycloaddition of azomethine ylides. These compounds were assayed by biochemical TrpRS inhibition, using in vitro experiments to test against various gram-positive and gram-negative strains, and using diffuse large B cell lymphoma (DLBCL) cell lines. Compound 6e was found to be the most active in vitro with IC50 values of 225 and 74 nM for tests against hmTrpRS and ecTrpRS, respectively. We also found a MIC90 value of 4 µg/mL for tests against S. aureus and IC50 values which ranged from 2.9 to 4.8 µM for tests against proliferation of DLBCL cell lines. Moreover, compound 6e was remarkably good at inducing bacterial autolysis in MRSA strains. Our results suggested that such an integrated approach could be an attractive and viable strategy for the discovery of novel TrpRS inhibitors as potential lead compounds for antibiotics and as novel anticancer agents. Discovery of novel spirooxindole-indenoquinoxaline TrpRS inhibitors as potential lead compounds with antibacterial and antitumor activities.

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.

In an effort to discover novel inhibitors of M. tuberculosis Caseinolytic proteases (ClpP1P2), a combination strategy of virtual high-throughput screening and in vitro assay was employed and a new pyrrole compound, 1-(2-chloro-6-fluorobenzyl)-2, 5-dimethyl-4-((phenethylamino)methyl)-1H-pyrrole-3-carboxylate was found to display inhibitory effects against H37Ra with an MIC value of 77 µM. In order for discovery of more potent anti-tubercular agents that inhibit ClpP1P2 peptidase in M. tuberculosis, a series of pyrrole derivatives were designed and synthesized based on this hit compound. The synthesized compounds were evaluated for in vitro studies against ClpP1P2 peptidase and anti-tubercular activities were also evaluated. The most promising compounds 2-(4-bromophenyl)-N-((1-(2-chloro-6-fluorophenyl)-2, 5-dimethyl-1H- pyrrolyl)methyl)ethan-1-aminehydrochloride 7d, ethyl 4-(((4-bromophenethyl) amino) methyl)-2,5-dimethyl-1-phenyl-1H-pyrrole-3-carboxylate hydrochloride 13i, ethyl 1-(4-chlorophenyl)-4-(((2-fluorophenethyl)amino)methyl)-2-methyl-5-phenyl-1H-pyrrole-3-carboxylate hydrochloride 13n exhibited favorable anti-mycobacterial activity with MIC value at 5 µM against Mtb H37Ra, respectively.

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.

A series of small molecules with novel pyrrolo[1,2-a]quinoxaline-based scaffold was designed via molecular hybridization of privileged agents active against Mycobacterium tuberculosis. Twenty-three compounds were synthesized and investigated for their antitubercular activities in vitro where ten compounds showed appreciable activities and moderate cytotoxicity. Compound 12g with MIC values of 5 μg/ml as a representative may possess better oral bioavailability and indicated high permeability by the parallel artificial membrane permeation assay of the blood-brain barrier (PAMPA-BBB). Further, the determination of enzyme inhibition and molecular docking study indicated that InhA may be the biological target of the active compounds. The results suggest the pyrrolo[1,2-a]quinoxaline hybrids as potential antitubercular leads for the development of new antitubercular agents.

In our previous study, FYL-67, a novel linezolid analogue with the morpholinyl ring replaced by a 4-(pyridin-2-yl)-1H-pyrazol-1-yl group, was demonstrated to own an excellent activity against Gram-positive organisms,such as methicillin-resistant Staphylococcus aureus (MRSA). However, metabolic biotransformation was not investigated. This study was performed to identify the phase I metabolites of FYL-67 using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The chemical structures were confirmed by comparison with corresponding chemical standards obtained internal. Primary elucidation of the metabolic pathway of FYL-67 in vitro was performed using liver preparations (microsomes and hepatocytes) from rats and humans, and SD (Sprague Dawley, rat, rattus norvegicus) rats were used for the study of in vivo approach. To the end, two metabolites (M1 and M2 ) were detected after in vitro as well as in vivo experiments. Based on LC-MS/MS analyses, the metabolites were demonstrated to be 5-(aminomethyl)-3-(3-fluoro-4-(4-(pyridin-2-yl)-1H-pyrazol-1-yl)phenyl)oxazolidin-2-one (M1 ) and 3-(3-fluoro-4-(4-(pyridin-2-yl)-1H-pyrazol-1-yl)phenyl)-5-(hydroxymethyl)oxazolidin-2-one (M2 ). Amide hydrolysis at acetyl group of FYL-67 leading to the formation of M1 was observed and suggested to play a major role in both in vivo and in vitro phase I metabolism of FYL-67. M1 was demonstrated to undergo a further oxidation to form M2 . In addition, the results indicated no species difference existing between rats and humans. The outcomes of our research can be utilized for the development and validation of the analytical method for the quantification of FYL-67 as well as its metabolites in biological samples. Furthermore, it is helpful to conduct studies of pharmacodynamics and toxicodynamics. Copyright © 2015 John Wiley & Sons, Ltd.

The asymmetric synthesis of 3-alkyl-3-hydroxyindolin-2-ones via direct aldol reaction of isatin with ketones catalyzed by natural amino acid salts is described, in which the phenylalanine lithium salt was found to be the best catalyst. This strategy was then applied to a variety of isatin and ketone substrates and the corresponding aldol products were obtained in excellent yields (up to 97%) with good to excellent enantioselectivities (up to 90%).

A series of novel teraryl oxazolidinone compounds was designed, synthesized, and evaluated for their antimicrobial activity and toxicities. The compounds with aromatic N-heterocyclic substituents at the 4-position of pyrazolyl ring showed better antibacterial activity against the tested bacteria than other compounds with different patterns of substitution. Among all potent compounds, 10f exhibited promising safety profile in MTT assays and in hERG K(+) channel inhibition test. Furthermore, its phosphate was found to be highly soluble in water (47.1 mg/mL), which is beneficial for the subsequent in vivo test. In MRSA systemic infection mice models, 10f phosphate exerted significantly improved survival protection compared with linezolid. The compound also demonstrated high oral bioavailability (F = 99.1%). Moreover, from the results of in vivo toxicology experiments, 10f phosphate would be predicted to have less bone marrow suppression.

A series of scutellarein-O-alkylamine derivatives were designed, synthesized and tested as multifunctional agents for the treatment of Alzheimer's disease (AD). The results showed that most of these compounds exhibited good multifunctional activities. Among them, compound 16d demonstrated significant metal chelating properties, moderate acetylcholinesterase (AChE) inhibitory and anti-oxidative activity, and excellent inhibitory effects on self-induced Aβ(1-42) aggregation, Cu(2+)-induced Aβ(1-42) aggregation, human AChE-induced Aβ(1-40) aggregation and disassembled Cu(2+)-induced aggregation of the well-structured Aβ(1-42) fibrils. Both kinetic analysis of AChE inhibition and molecular modeling study suggested that 16d binds simultaneously to the catalytic active site and peripheral anionic site of AChE. Moreover, compound 16d showed a good protective effect against H2O2-induced PC12 cell injury, with low toxicity in SH-SY5Y cells. Furthermore, the step-down passive avoidance test showed this compound significantly reversed scopolamine-induced memory deficit in mice. Thus, 16d was shown to be an interesting multifunctional lead compound worthy of further study.

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.

DB-6, with an IUPAC name of (Z)-5-(2,4-di-tert-butyl-6-((2,4-dioxothiazolidin-5-ylidene)methyl)phenyl)-5'-methyl-7,7'-dimethoxy-[4,4'-bibenzo[d][1,3]dioxole]-5,5'-dicarboxylate, is an investigational agent for acute liver failure. The focus of this study is the identification and characterization of major unknown impurities in DB-6 bulk drug samples. Four major impurities of DB-6 were detected by a high-performance liquid chromatography (HPLC) method and designated as IMP-I, IMP-II, IMP-III and IMP-IV. Accurate masses of these impurities were determined by using a Q-TOF mass spectrometer. Based on chromatographic, spectrometric data and plausible chemical transformation mechanism, the structures of IMP-I, IMP-II, IMP-III and IMP-IV were identified, respectively, as bifendate, (E)-5-(2,4-di-tert-butyl-6-((2,4-dioxothiazolidin-5-ylidene)methyl)phenyl)-5'-methyl-7,7'-dimethoxy-[4,4'-bibenzo[d][1,3]dioxole]-5,5'-dicarboxylate, (Z)-5-(3,5-di-tert-butyl-2-hydroxybenzylidene) thiazolidine-2,4-dione and bis(2,4-di-tert-butyl-6-((Z)-(2,4-dioxothiazolidin-5-ylidene)methyl)phenyl)-7,7'-dimethoxy-[4,4'-bibenzo[d][1,3]dioxole]-5,5'-icarboxylate. The impurities were isolated by preparative-HPLC or preparative high-speed counter-current chromatography and their structures were confirmed by NMR spectroscopy.

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.

A concise, environmentally benign, and cost-effective route was developed for the large-scale preparation of 1, a novel oxazolidinone antibacterial candidate. The key intermediate 2-(1-(2-fluoro-4-nitrophenyl)-1H-pyrazol-4-yl)pyridine 7 was prepared with high purity by mild deamination of the regioisomeric mixture 21. The mixture was prepared from a nucleophilic SNAr reaction by selective C–N coupling of the secondary amine functionality of 4-(pyridin-2-yl)-1H-pyrazol-3-amine 14 with 1,2-difluoro-4-nitrobenzene 10 in optimized conditions with the primary amine group remaining intact. The gaseous nitrogen release rate and reaction mixture temperature of the deamination step can be well controlled by altering the feeding manner, thereby providing safety guarantees. The optimized synthetic strategy of 1 with an overall yield of 27.6%, including seven sequential transformations by only five solid–liquid isolations, significantly improved the product separation workup. The strategy bypassed time-consuming and ...

Twelve 2-(2-((4-substituted-phenoxy)methyl)-1H-benzo[d]imidazol-1-yl)-acetylhydrazone derivatives were synthesized. These synthesized compounds have been tested for their antitumor activity in vitro against A549, MDA-MB-231, A375, and HCT116 cancer cells using the MTT assay. Among them, the compounds containing hydroxyl on position 2 at phenyl of hydrazone displayed a good anticancer activity, especially those containing two hydroxyl on 2 and 4 place at phenyl of hydrazone, for example, N′-(2,4-dihydroxybenzylidene)-2-(2-((p-tolyloxy)methyl)-1H-benzo[d]imidazol-1-yl)acetohydrazide 7b, N′-(2,4-dihydroxybenzylidene)-2-(2-(phenoxymethyl)-1H-benzo[d]imidazol-1-yl) acetohydrazide 7f, 2-(2-((4-chlorophenoxy)methyl)-1H-benzo[d]imidazol-1-yl)-N′-(2,4-dihydroxybenzylidene)acetohydrazide 7j, have excellent antitumor activity. The results revealed that hydroxyl on position 2 at phenyl of hydrazone was necessary for anticancer activity, and another hydroxyl group on 4 place at phenyl can increase the inhibitory activity. An electron-withdrawing substituent at position 4 on phenyl ring of 2-phenoxylbenzimidazole was favorable to increasing anticancer activity toward MDA-MB-231, A375, and HCT116 cells.

Piperlongumine (PL) shows an inhibitory effect on tumor growth; however, lipophilicity has restricted its further applications. Nanotechnology provides an effective method to overcome the poor water solubility of lipophilic drugs. Polymeric micelles with small particle size can passively target tumors by the enhanced permeability and retention (EPR) effect, thus improving their anti-tumor effects. In this study, to improve the water solubility and anti-tumor activity of PL, PL encapsulated polymeric micelles (PL micelles) were prepared by a solid dispersion method. The prepared PL micelles showed a small particle size and high encapsulation efficiency, which could be lyophilized into powder, and the re-dissolved PL micelles are homogenous and stable in water. In addition, a sustained release behavior of PL micelles was observed in vitro. Encapsulation of PL into polymeric micelles could increase the cytotoxicity, cellular uptake, reactive oxygen species (ROS) and oxidized glutathione (GSSG), and reduce glutathione (GSH) levels in vitro. Encapsulation of PL into polymeric micelles enhanced its inhibitory effect on neovascularization both in vitro and in vivo. Compared with free PL, PL micelles showed a stronger inhibitory effect on the proliferation, migration, invasion and tube formation of human umbilical vein endothelial cells (HUVECs). Additionally, in a transgenic zebrafish model, embryonic angiogenesis was inhibited by PL micelles. Furthermore, PL micelles were more effective in inhibiting tumor growth and prolonging survival in a subcutaneous CT-26 murine tumor model in vivo. Therefore, our data revealed that the encapsulation of PL into biodegradable polymeric micelles enhanced its anti-angiogenesis and anti-tumor activities both in vitro and in vivo.

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.

The asymmetric synthesis of 3-alkyl-3-hydroxyindolin-2-ones via direct aldol reaction of isatin with ketones catalyzed by natural amino acid salts is described, in which the phenylalanine lithium salt was found to be the best catalyst. This strategy was then applied to a variety of isatin and ketone substrates and the corresponding aldol products were obtained in excellent yields (up to 97%) with good to excellent enantioselectivities (up to 90%).

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.

Honokiol, widely known as an antitumor agent, has been used as an antiangiogenesis drug lead. In this paper, 47 honokiol analogues and derivatives were investigated for their antiangiogenic activity by application of the transgenic zebrafish screening model, antiproliferative and cytotoxic activity against HUVECs, and three tumor cell lines by MTT assay. 3',5-Diallyl-2,4'-dihydroxy-[1,1'-biphen-yl]-3,5'-dicarbaldehyde (8c) was found to suppress the newly grown segmental vessels from the dorsal aorta of zebrafish and prevent inappropriate vascularization as well as exhibit more potent inhibitory effects on the proliferation of HUVECs, A549, HepG2, and LL/2 cells (IC(50) = 15.1, 30.2, 10.7, and 21.7 μM, respectively) than honokiol (IC(50) = 52.6, 35.0, 16.5, and 65.4 μM, respectively). Analogue 8c also effectively inhibited the migration and capillary-like tube formation of HUVECs in vitro. The antiangiogenic effect and antiproliferative activity of these structurally modified honokiol analogues and derivatives have led to the establishment of a structure-activity relationship.

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.

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.

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.

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.

In the title compound, C13H10FNO5S, the dihedral angle between the benzene rings is 47.63 (14)°. In the crystal, π–π stacking occurs between nearly parallel benzene rings of adjacent molecules, the centroid–centroid distance being 3.7806 (16) Å. Weak intermolecular C—H...O hydrogen bonding is also present in the crystal structure.

In the molecule of the title compound, C13H13BrN2O2S, the dihedral angle formed by the pyridine and benzene rings is 66.87 (3)°. An intramolecular N—H...Br hydrogen bond is observed. In the crystal structure, N—H...O hydrogen bonds, C—H...π interactions and aromatic π–π stacking interactions [centroid–centroid distance = 3.757 (14) Å] link the molecules into a three-dimensional network.

This paper describes the application of high-performance counter-current chromatography (HPCCC) as a fast, useful and economic alternative for the separation and purification of seven honokiol derivatives (two of them are isomers), which were synthesized by a one-pot procedure. Five honokiol derivatives were successfully separated by n-hexane-ethyl acetate-methanol-water solvent system at three different volume ratios in a step-gradient elution. Two derivatives were obtained through a cycle elution mode. The whole separation process produced 366.3 mg, 323.6 mg, 242.8 mg, 216.2 mg, 203.5 mg, 185.8 mg and 279.3 mg of 3'-formylhonokiol (1), 2'-methoxy-3'-formylhonokiol (2), 2'-methoxyhonokiol (3), 4-methoxyhonokiol (4), 3',5-diformylhonokiol (5), 2',4-dimethoxy-3'-formylhonokiol (6) and 2',4-dimethoxyhonokiol (7) from crude sample of 3 g with purities of 98.7%, 99.3%, 98.6%, 98.2%, 99.0%, 98.4% and 99.2%, respectively. The purities and structural identification were determined by HPLC, (1)H NMR, (13)C NMR and mass spectroscopy.

A series of honokiol analogues were synthesized by modifying the 5- and/or 3'-position(s) of honokiol to assess their anti-tumor effects. Some compounds exerted more potent anti-proliferative activities than those of honokiol on K562 leukemia cells, A549 alveolar basal epithelial cells, SPC-A1 adenocarcinoma cells and A2780 human ovarian carcinoma cells in vitro. Compounds 2b, 3a, and 3c displayed most potent anti-proliferative activities against these tested cell strains and their anti-drug resistance effects were evaluated in vitro on cisplatin-resistant A2780 human ovarian carcinoma cells. The structure-activity relationship was also proposed.

Both analytical and preparative high-speed counter-current chromatography (HSCCC) were used to isolate and separate chemical bioactive constituents from the seeds of Millettia pachycarpa Benth, a famous traditional Chinese medicine. Three rotenoids and one isoflavone were successfully purified for the first time by HSCCC with a two-phase solvent system composed of n -hexane–ethyl acetate–methanol–water (HEMWat) (1:0.8:1:0.6, v/v/v/v). The separation parameters were first performed on the analytical HSCCC and optimized conditions were then scaled up to preparative HSCCC. The separation produced 160.2 mg tephrosin, 14.6 mg 4′,5′-dimethoxy-6,6-dimethylpyranoisoflavone, 109.4 mg deguelin, 6.7 mg 6a,12a-dehydrodeguelin with respective purities of 95, 93, 95, 95%, in one single run from 400 mg crude extract of the seeds of M. pachycarpa Benth. The purity of the isolated compounds was analyzed by high-performance liquid chromatography (HPLC) and their structures were identified by electrospray ionization mass spectrometry (ESI-MS); 1 H nuclear magnetic resonance ( 1 H NMR) and 13 C nuclear magnetic resonance ( 13 C NMR) analysis. This paper is an excellent example of the role that CCC is playing in isolating active compounds for pre-clinical trials of new chemical entities, even when scaling up between centrifuges from different manufacturers.

In our program to synthesize a series of novel derivatives as potential analogs of honokiol for anti-tumor treatment, we have found that at least three of the derivatives of honokiol showed more potency to inhibit the proliferation of K562 leukemia cells and SPC-A1 adenocarcinoma cells. As a critical step to our further series synthesis of derivatives of honokiol, three derivatives of honokiol composed of two isomers and one compound with two formyl groups, which were hardly separated by common purification methods, needed to be rapidly separated and purified. The present work describes analytical and preparative high-speed counter-current chromatography (HSCCC) for the isolation and purification of these three C-formylation derivatives of honokiol, named 3'-formylhonokiol, 5-formylhonokiol and 3',5-diformylhonokiol, respectively. The solvent system for HSCCC separation was composed of hexane-ethyl acetate-methanol-water with the ratio of 1:0.4:1:0.4 (v/v). The one-step purification produced 157.8 mg, 121.6 mg and 21.2 mg of 3'-formylhonokiol, 5-formylhonokiol, 3',5-diformylhonokiol from crude sample of 400mg with purities of 98.6%, 99.2% and 99.6%, respectively, in an elution time of 2.5 h. The purities and structural identification were determined by HPLC, (1)H NMR, (13)C NMR and mass spectroscopy. Their anti-proliferation effects on K562, A549 and SPC-A1 cell lines were evaluated by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay.

In the molecular structure of the title compound, C15H11NO4S3, the 1,2,4-dithiazolone and central benzene rings are approximately coplanar, making a dihedral angle of 3.08 (7)°. The central benzene ring and the 4-methylbenzene ring subtend a dihedral angle of 57.47 (8)°. In the crystal, π–π stacking occurs between the central benzene ring and the 1,2,4-dithiazolone ring of adjacent molecules, which are aligned almost parallel, the centroid–centroid distance being 3.555 (7) Å.