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Five series of novel carbazole derivatives containing an aminoguanidine, dihydrotriazine, thiosemicarbazide, semicarbazide or isonicotinic moiety were designed, synthesised and evaluated for their antimicrobial activities. Most of the compounds exhibited potent inhibitory activities towards different bacterial strains (including one multidrug-resistant clinical isolate) and one fungal strain with minimum inhibitory concentrations (MICs) between 0.5 and 16 µg/ml. Compounds 8f and 9d showed the most potent inhibitory activities (MICs of 0.5–2 µg/ml). Furthermore, compounds 8b, 8d, 8f, 8k, 9b and 9e with antimicrobial activities were not cytotoxic to human gastric cancer cell lines (SGC-7901 and AGS) or a normal human liver cell line (L-02). Structure–activity relationship analyses and docking studies implicated the dihydrotriazine group in increasing the antimicrobial potency and reducing the toxicity of the carbazole compounds. In vitro enzyme activity assays suggested that compound 8f binding to dihydrofolate reductase might account for the antimicrobial effect.

Adding to past success in developing non-nucleoside reverse transcriptase inhibitors (NNRTIs), we report herein our efforts to optimize an FDA-approved NNRTI, doravirine, into a series of novel biphenyl-substituted pyridone derivatives. A strategy focused on harnessing the X-ray crystal structure of doravirine, coupled with computer simulations, to guide the design of conformationally constrained analogs led to the discovery of ZLM-66, which provided comparable inhibitory potency to doravirine against wild-type HIV-1 (EC

Six series of 4-(benzo[c][1,2,5]thiadiazol-5-yl)-3(5)-(6-methylpyridin-2-yl)- pyrazoles 18a–d, 19a–d, 22a–d and 3(5)-(6-methylpyridin-2-yl)-4-(thieno[3,2,-c]- pyridin-2-yl)pyrazoles 20a–d, 21a–d, 23c, 23d have been synthesized and evaluated for their activin receptor-like kinase 5 (ALK5) and p38α mitogen activated protein (MAP) kinase inhibitory activities in enzymatic assays. Among these compounds, the most active compound, 22c, inhibited ALK5 phosphorylation with an IC50 value of 0.030 μM in the enzymatic assay. Compound 22c showed four-fold more potent activity against ALK5 kinase than the clinical candidate, compound LY-2157299. The selectivity index of 22c against p38α MAP kinase is 235, which is much higher than that of LY-2157299 (4) and equally selective to that of EW-7197 (218). Compound 22c effectively suppressed protein and mRNA expression of collagen I and α-SMA in TGF-β-induced LX-2 human hepatic stellate cell (HSC), this result shows that compound 22c has the ability to inhibit the activation of HSC. Compound 22c is expected to be a preclinical candidate for the treatment of hepatic fibrosis.

Transforming growth factor (TGF-β), a key mediator of tumor growth and metastasis, has been recognized as an important cancer drug target. A series of benzo[c][1,2,5]thiadiazol-5-yl imidazoles (14a–g) and thieno[3,2-c]-pyridin-2-yl imidazoles (20a–g) were designed, synthesized, and evaluated for their activin receptor-like kinase 5 (ALK5) activities. Among these compounds, 14c showed the highest activity (IC50 = 0.008 μM) against ALK5 kinase, which was 16.1-fold and 1.8-fold higher than those of positive control compounds LY-2157299 (IC50 = 0.129 μM) and EW-7197 (IC50 = 0.014 μM), respectively. Compound 14g (350) showed the highest selectivity index of ALK5 against p38α MAP kinase, which was significantly higher than that of positive control compounds LY-2157299 (4) and EW-7197 (211). The inhibitory effects of compound 14c on TGF-β-induced Smad signaling and cell motility were studied in SPC-A1, HepG2 and HUVEC cells using western blot analysis and wound healing assay. ADMET prediction analysis showed that compounds 14c and 14g had good pharmacokinetics and drug-likeness behaviors.

Several series of novel tryptophan-derived rhodanine derivatives were synthesized and identified as potential competitive PTP1B inhibitors and antibacterial agents. Among the compounds studied, 10b was found to have the best in vitro inhibition activity against PTP1B (IC50 = 0.36 ± 0.02 μM). In addition, the compounds also showed potent inhibition against other PTPs, especially CDC25B. Molecular docking analysis demonstrated that compounds 7c and 10b could occupy both the catalytic site and the adjacent pTyr binding site simultaneously. The compounds also showed higher levels of activity against gram-positive strains, the gram-negative strain Escherichia coli 1924, and multidrug-resistant gram-positive bacterial strains. Compounds 7c, 8c, 9e, 10a, and 10c had comparable or more potent antibacterial activity than the positive controls.

Three novel series of dihydrotriazine derivatives bearing 1,3-diaryl pyrazole moieties were designed, synthesized and evaluated in terms of their antibacterial and antifungal activities. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gram-negative bacterial strains with minimum inhibitory concentration values in the range of 1–64 µg/mL. Compounds 4b and 4c presented the most potent inhibitory activity against Gram-positive bacteria (S. aureus 4220, MRSA 3167, QRSA 3519) and Gram-negative bacteria (E. coli 1924), with minimum inhibitory concentration values of 1 or 2 µg/mL. Compared with previous studies, these compounds exhibited a broad spectrum of inhibitory activity. The cytotoxic activity of the compounds 4a, 4b, 4c and 11n were assessed in L02 cells. In vitro enzyme study implied that compound 4c exerted its antibacterial activity through DHFR inhibition.

Three series of ursolic acid derivatives containing an aminoguanidine moiety were designed, synthesized, and evaluated for anti-bacterial and anti-inflammatory activity. Some compounds displayed potent anti-bacterial activity against Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gram-negative bacterial strains, with minimum inhibitory concentration (MIC) values in the range of 2–64 µg/mL. Compounds 3a, 5a, and 7l showed significant inhibitory activity against the Gram-positive bacterial strain Staphylococcus aureus RN 4220, the Gram-negative bacterial strain Escherichia coli 1924, and four multidrug-resistant Gram-positive bacterial strains, with MIC values of 2 and 4 µg/mL. In anti-inflammatory tests, most of the compounds exhibited potent activity, in particular compound 3a displayed the most potent activity with 81.61% inhibition after intraperitoneal administration, which was more potent than ursolic acid and the reference drugs (ibuprofen and indomethacin). The cytotoxic activity of compound 3a was assessed in HeLa, Hep3B, and A549 cells.

Three series of new imidazole-fused imidazo[2,1-b][1,3,4]thiadiazole analogues (compounds 20 a-g, 21 a-g, and 22 a-g) have been synthesized, and their antibacterial and antifungal activities have been evaluated. All the target compounds showed strong antifungal activity and high selectivity for the test fungus Candida albicans over Gram-positive and -negative bacteria. N-((4-(2-Cyclopropyl-6-(4-fluorophenyl)imidazo[2,1-b][1,3,4]thiadiazol-5-yl)-5-(6-methyl-pyridin-2-yl)-1H-imidazol-2-yl)methyl)aniline (21 a) showed the highest activity against C. albicans (MIC50 =0.16 μg/mL), 13 and three times that of the positive control compounds gatifloxacin and fluconazole, respectively. Compounds 21 a and 20 e did not show cytotoxicity against human foreskin fibroblast-1 cells, and compound 21 a was as safe as the positive control compounds in hemolysis tests. These results strongly suggest that some of the compounds produced in this work have value for development as antifungal agents.

Drugs of targeting both activin receptor-like kinase 5 (ALK5) and p38α have therapeutic advantages, making them attractive treatment options for tumors. Two series of 4-(1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 13a–g and 4-(1-methyl-1H-indazol-5-yl)-5-(6-methylpyridin-2-yl)-1H-imidazoles 20a–g were synthesized and evaluated for ALK5 and p38α mitogen-activated protein kinase inhibitory activity. The most potent compound, 13c (J-1090), inhibited ALK5- and p38α-mediated phosphorylation with half-maximal inhibitor concentrations of 0.004 μM and 0.004 μM, respectively, in the enzymatic assay. In this study, the effectiveness of 13c in transforming growth factor (TGF-β)-exposed U87MG cells was investigated using western blotting, immunofluorescence assays, cell migration assay, invasion assay, and RT-PCR analysis. 13c inhibited the protein expression of Slug and the protein and RNA expression of the mesenchymal-related proteins N-cadherin and vimentin. Furthermore, 13c markedly suppressed TGF-β-induced epithelial-to-mesenchymal transition (EMT), migration, and invasion in U87MG cells. These results suggest that 13c is a novel inhibitor of ALK5 with potential utility in the treatment of human glioma.

Connexin-40 (Cx40) and Cx43 are the principal components of gap junctions. Dysregulation of connexin expression is clinically related to cardiac pathologies. 25-Hydroxy protopanaxadiol [25-OH-PPD, 20 (R)-dammarane-3β, 12β, 20, 25-tetrol], known as AD2, is a novel protopanaxadiol extracted from Panax ginseng that exhibits many pharmacological activities, but its effects on cardiac gap junctions are poorly understood. The aim of this study was to evaluate the effects of AD2 on angiotensin II (Ang II)-induced Cx40 and Cx43 dysregulation. In this study, isolated beating rat atria were perfused with Ang II (5 μM) for 1 h to induce Cx40 and Cx43 dysregulation. The effects of AD2 (1.6, 16, and 160 μg/100 g body weight) on Ang II-induced hemodynamics in rats were analyzed by biological recorder, and changes in proteins levels were analyzed by western blotting. The results showed that AD2 ameliorated Ang II-induced hyper hemodynamics and abnormal P-waves, and prevented fibrotic collagen deposition (3.77% ± 1.64%–26.31% ± 1.64% with Ang II, 5.76% ± 0.94% with AD2). Ang II upregulated expression of nuclear factor kappa B, activator protein 1, and transforming growth factor β1, and downregulated of Cx40 and Cx43 expression, which were inhibited by AD2 concomitantly with increased of AMP-activated protein kinase (AMPK) expression via liver kinase B1 activation. The present findings suggest that AD2 inhibited Ang II-induced dysregulation of Cx40 and Cx43 via activation of AMPK signaling, thus highlighting the promise and utility of AD2 for treatment of connexin dysregulation-related heart disease.

Hypoxia-inducible factor 1α (HIF-1α) is a known regulator of tumor cell proliferation, migration, and angiogenesis. The presence of a high concentration of HIF-1α is positively correlated with the severity of cancer. Therefore, the inhibition of this pathway represents an important therapeutic target for the treatment of various types of cancer. Here, we designed and synthesized 30 panaxadiol (PD) derivatives and evaluated their inhibitory activities against HIF-1α transcription. Of these, compound 3l exhibited the most promising inhibitory activity (IC50 = 3.7 µM) and showed significantly decreased cytotoxicity compared with PD. Compound 9e exhibited the strongest cytotoxic effect and may be considered for further preclinical development.

BACKGROUND AND PURPOSE: Arctigenin, a major bioactive component of Fructus arctii, has been reported to have antidepressant‐like effects. However, the mechanisms underlying these effects are still unclear. Neuroinflammation can be caused by excessive production of proinflammatory cytokines in microglia via high‐mobility group box 1 (HMGB1)/TLR4/NF‐κB and TNF‐α/TNFR1/NF‐κB signalling pathways, leading to depression. In this study, we have investigated the antidepressant mechanism of arctigenin by conducting in vitro and in vivo studies. EXPERIMENTAL APPROACH: The effects of chronic unpredictable mild stress (CUMS) on wild‐type (WT) and TLR4(−/−) mice were examined. Antidepressant‐like effects of arctigenin were tested using the CUMS‐induced model of depression in WT mice. The effects of arctigenin were assessed on the HMGB1/TLR4/NF‐κB and TNF‐α/TNFR1/NF‐κB signalling pathways in the prefrontal cortex (PFC) of mouse brain and HMGB1‐ or TNF‐α‐stimulated primary cultured microglia. The interaction between HMGB1 and TLR4 or TNF‐α and TNFR1 with or without arctigenin was examined by localized surface plasmon resonance (LSPR) and co‐immunoprecipitation assays. KEY RESULTS: The immobility times in the tail suspension test (TST) and forced swimming test (FST) were reduced in TLR4(−/−) mice, compared with WT mice. Arctigenin exhibited antidepressant‐like effects. Arctigenin also inhibited microglia activation and inflammatory responses in the PFC of mouse brain. Arctigenin inhibited HMGB1 and TLR4 or TNF‐α and TNFR1 interactions, and suppressed both HMGB1/TLR4/NF‐κB and TNF‐α/TNFR1/NF‐κB signalling pathways. CONCLUSIONS AND IMPLICATIONS: Arctigenin has antidepressant‐like effects by attenuating excessive microglial activation and neuroinflammation through the HMGB1/TLR4/NF‐κB and TNF‐α/TNFR1/NF‐κB signalling pathways. This suggests that arctigenin has potential as a new drug candidate suitable for clinical trials to treat depression.

At present, diseases resulting from various reasons have been causing deadly fears to humans and previously incogitable losses to health. Meanwhile, the patient compliance has been weakening because of drug resistance and serious drug adverse effects. There is therefore an urgent need for the development of novel structural agents. Rhodanine derivatives have exhibited wide biological activities, as well as significant industrial applications, which suggests that rhodanine heterocycle represents a key structural motif in heterocyclic chemistry and occupies a prominent position in drug discovery. Here, we review some deadly defects of clinical medicines to the therapy of diseases and important advances on rhodanine derivatives in drug researches (e.g. as anti-diabetic, anti-viral, antiinflammatory, anti-microbial, anti-tumor agents and inhibitors for Alzheimer Disease), indicating that rhodanine heterocycle could be used as a significant pharmacophore to develop novel pharmacological active molecules. It is believed that the review is of importance for new ideas in the development of and rational designs of rhodanine-based drugs.

Ursolic acid derivatives containing oxadiazole, triazolone, and piperazine moieties were synthesized in an attempt to develop potent anti-inflammatory agents. Structures of the synthesized compounds were elucidated by 1H NMR, 13C NMR, and HRMS. Most of the synthesized compounds showed pronounced anti-inflammatory effects at 100 mg/kg. In particular, compound 11b, which displayed the most potent anti-inflammatory activity of all of the compounds prepared, with 69.76% inhibition after intraperitoneal administration, was more potent than the reference drugs indomethacin and ibuprofen. The cytotoxicity of the compounds was also assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and no compounds showed any appreciable cytotoxic activity (IC50 >100 μmol/L). Furthermore, molecular docking studies of the synthesized compounds were performed to rationalize the obtained biological results. Overall, the results indicate that compound 11b could be a therapeutic candidate for the treatment of inflammation.

A series of novel naphthyl-diarylpyrimidine (DAPY) derivatives were designed and synthesized to explore the entrance channel of the non-nucleoside reverse transcriptase inhibitors binding pocket (NNIBP) by incorporating different flexible side chains at the C-6 position. The biological evaluation results showed that all analogues possessed promising HIV-1 inhibitory activity at the nanomolar concentration range. Three compounds (7, 9 and 39) displayed excellent potency against WT HIV-1 strain with EC50 values ranging from 5 to 10 nM and high selectivity indexes (SI = 3504, 30488 and 22846, respectively), which were higher than for nevirapine and comparable to the values for etravirine. The RT inhibition activity, preliminary structure-activity relationship and molecular docking study showed that the side chain at the C-6 position of the DAPYs occupied the entrance channel and significantly influenced anti-HIV activity and selectivity. Additionally, the physicochemical properties were investigated to evaluate the drug-like features, which indicated that introducing various substituents on the pyrimidine ring can improve solubility.

In the present study, three series of novel celastrol derivatives were designed and synthesised by modifying the carboxylic acid at the 20th position with amino acid, amine, and triazole derivatives. All the synthesised compounds were screened for their anticancer activities using MTT assay against AGS, MGC-803, SGC-7901, HCT-116, A549, HeLa, BEL-7402, and HepG-2 cell lines. Most of the synthesised compounds exhibited potent antiproliferative effects. The most promising compound 3-Hydroxy-9β,13α-dimethyl-2-oxo-24,25,26-trinoroleana-1(10),3,5,7-tetraen-29-oic amide, N-(R)-methyl-3-(1H-indol-2-yl)propanoate (11) showed considerable high anticancer activity against AGS cell lines, with an IC50 value of 0.44 μM, and considerably higher activities against HCT-116, BEL-7402, and HepG-2 cell lines, with IC50 values of 0.78, 0.63, and 0.76 μM, respectively. The results of apoptosis tests and molecular docking study of compound 11 binding to Caspase-3 revealed that its mechanism of action with antiproliferative was possibly involved in inducing apoptosis by inducing the activation of caspase-3.

In the current work, 13 novel panaxadiol (PD) derivatives were synthesized by reacting with chloroacetyl chloride and bromoacetyl bromide. Their in vitro antitumor activities were evaluated on three human tumor cell lines (HCT-116, BGC-823, SW-480) and three normal cells (human gastric epithelial cell line-GES-1, hair follicle dermal papilla cell line-HHDPC and rat myocardial cell line-H9C2) by MTT assay. Compared with PD, the results demonstrated that compound 1e, 2d, 2e showed significant anti-tumor activity against three tumor cell lines, the IC50 value of compound 2d against HCT-116 was the lowest (3.836μM). The anti-tumor activity of open-ring compounds are significantly better than the compounds of C-25 cyclization. Compound 1f, 2f, 2g showed the strong anti-tumor activity. The IC50 value of compound 2g against BGC-823 and SW-480 were the lowest (0.6μM and 0.1μM, respectively). Combined with cytotoxicity test, the IC50 value of compound 1e, 2d, 2e are greater than 100. the open-ring compounds (1f, 2f, 2g) showed a strong toxicity. The toxicity of 1f is lower than 2f and 2g. These compounds may be useful for the development of novel antiproliferative agents.

A series of 1,4-dihydro-1,3,5-triazine derivatives were designed and synthesized and their antibacterial and antifungal activities were evaluated. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gram-negative bacterial strains, with minimum inhibitory concentrations (MICs) in the range of 2.1–181.2 μmol/L. Compounds 7a and 7c presented the most potent inhibitory activities against Gram-positive bacteria ( e.g. , Staphylococcus aureus 4220), Gram-negative bacteria ( e.g. , Escherichia coli 1924), and the fungus Candida albicans 7535, with MICs of 2.1 or 4.1 μmol/L. Especially, compound 7a was the most potent, with an MIC of 2.1 μmol/L against four multidrug-resistant, Gram-positive bacterial strains. The cytotoxic activity of the compound 7a , 7c and 7f was assessed in HepG2 cells, and the results suggest that 1,4-dihydro-1,3,5-triazine derivatives bearing a 6-benzyloxynaphthalen moiety are interesting scaffolds for the development of novel antibacterial agents.

The transcription factor hypoxia-inducible factor-1α (HIF-1α) plays an important role in apoptosis, metastasis, and proliferation and is recognized as an important potential therapeutic target for cancer. Six series of 3(5)-(6-methylpyridin-2-yl)-4-(quinolin-4-yl)pyrazoles (11a-d, 12a-d, and 18a-d) and 3(5)-(6-methylpyridin-2-yl)-4-(2-phenyl-pyridin-4-yl)pyrazoles (19a-d, 20a-d, and 21a-d) were synthesized and evaluated for activin receptor-like kinase 5 (ALK5) and HIF-1α inhibitory activity at the enzyme and cell levels. The effect of the lead compound 20d (J-1012) on HIF-1α activation in HCT116 cells was investigated. J-1012 markedly decreased the hypoxia-induced or TNF-induced accumulation of HIF-1α protein dose-dependently. Analysis revealed that J-1012 inhibited HIF-1α protein synthesis, without affecting the degradation of HIF-1α protein. Furthermore, by inhibiting the activation of HIF-1α, J-1012 suppressed the metastasis and proliferation and promoted apoptosis of HCT116 cells. These results suggest that J-1012 may be a potential therapeutic agent against human colon cancer.

20(R)-25-hydroxyprotopanaxadiol (25-OH-PPD) is a natural compound showing a variety of anti-tumor effects. In an attempt to search for a new anti-cancer compound with higher antitumor activities, we designed and synthesized a series of 25-OH-PPD derivatives. Cytotoxicity assay of these derivatives towards MCF-7, A549, U87, HO-8901, Hela cancer cell lines and normal IOSE144 cell lines were tested by MTT assay. Results showed that compared with compound 25-OH-PPD, Compounds 4, 5, 6, 10, 11 showed strong anticancer activity, and all compounds showed low toxicity or no toxicity for normal cells. In particular, compound 6 exhibited the best anti-tumor activity in all cancer cell lines (MCF-7, A549, U87, HO-8901, and Hela) with IC50 values of 5.04 μM, 1.36 μM, 3.24 μM, 3.47 μM, 4.57 μM, respectively. Among the five cell lines, all the compounds showed strong inhibition on A549 cells. Further studies showed that Compound 6 significantly inhibited the proliferation of A549 cells by inducing apoptosis. Our results indicate that Compound 6 is a potential anticancer inhibitor and provides a theoretical basis for further research.

Emodin is a cell arrest and apoptosis-inducing compound that is widely distributed in different plants (rhubarb, aloe), lichens and terrestrial fungi, and also isolated from marine-derived fungi and marine sponge-associated fungi. In this study, we designed and synthesized a novel series of emodin derivatives by binding emodin to an amino acid using linkers of varying lengths and composition, and evaluated their anti-proliferative activities using HepG2 cells (human hepatic carcinoma), MCF-7 cells (human breast cancer) and human normal liver L02 cells. Most of these derivatives showed moderate to potent anti-proliferative activities. Notably, compound 7a exhibited potent anti-proliferative activity against HepG2 cells with the half maximal inhibitory concentration (IC50) value of 4.95 µM, which was enhanced 8.8-fold compared to the parent compound emodin (IC50 = 43.87 µM), and it also exhibited better selective anti-proliferative activity and specificity than emodin. Moreover, further experiments demonstrated that compound 7a displayed a significant efficacy of inducing apoptosis through mitochondrial pathway via release of cytochrome c from mitochondria and subsequent activation of caspase-9 and caspase-3, inducing cell arrest at G0/G1 phase, as well as suppression of cell migration of tumor cells. The preliminary results suggested that compound 7a could be a promising lead compound for the discovery of novel anti-tumor drugs and has the potential for further investigations as an anti-cancer drug.

The transforming growth factor-&beta, (TGF-&beta, ), in which overexpression has been associated with various diseases, has become an attractive molecular target for the treatment of cancers. Thirty-two quinoxaline-derivatives of 3-substituted-4-(quinoxalin-6-yl) pyrazoles 14a&ndash, d, 15a&ndash, d, 16a&ndash, d, 17a&ndash, d, 18a&ndash, d, 19a&ndash, d, 25a, 25b, 25d, 26a, 26b, 26d, 27b, and 27d were synthesized and evaluated for their activin TGF-&beta, type I receptor kinase and p38&alpha, mitogen activated protein (MAP) kinase inhibitory activity in enzymatic assays. Among these compounds, the most active compound 19b inhibited TGF-&beta, type I receptor kinase phosphorylation with an IC50 value of 0.28 &micro, M, with 98% inhibition at 10 &micro, M. Compound 19b also had good selectivity index of &gt, 35 against p38&alpha, MAP kinase, with 9.0-fold more selective than clinical candidate, compound 3 (LY-2157299). A molecular docking study was performed to identify the mechanism of action of the synthesized compounds and their good binding interactions were observed. ADMET prediction of good active compounds showed that these ones possess good pharmacokinetics and drug-likeness behavior.

Two series of 1,3-diphenyl-1H-pyrazole derivatives containing rhodanine-3-alkanoic acid groups were identified as competitive protein tyrosine phosphatase 1B (PTP1B) inhibitors. Among the compounds studied, IIIv was found to have the best in vitro inhibition activity against PTP1B (IC50 = 0.67 ± 0.09 µM) and the best selectivity (9-fold) between PTP1B and T-cell protein tyrosine phosphatase (TCPTP). Molecular docking studies demonstrated that compounds IIIm, IIIv and IVg could occupy simultaneously at both the catalytic site and the adjacent pTyr binding site. These results provide novel lead compounds for the design of inhibitors of PTP1B as well as other PTPs.

Two series of 5-aryl-furan derivatives bearing a phenylalanine- or isoleucine-derived rhodanine moiety were identified as competitive protein tyrosine phosphatase 1B (PTP1B) inhibitors. Among the compounds studied, 5g was found to have the best PTP1B inhibitory potency (IC50 = 2.66 ± 0.16 µM) and the best cell division cycle 25 homolog B (CDC25B) inhibitory potency (IC50 = 0.25 ± 0.02 µM). Enzymatic data together with molecular modeling results demonstrated that the introduction of a sec-butyl group at the 2-position of the carboxyl group remarkably improved the PTP1B inhibitory activity.

Background: An alarming increment in pathogenic resistance to existing anti-microbial agents is a serious problem and the treatment of these bacterial infections is becoming increasingly challenging. Therefore, there is an urgent need to develop novel antimicrobial agents. Objective: As a part of our ongoing studies toward the development of novel antibacterial agents, the synthesis and antibacterial activity of a series of (Z)-5-((3-phenyl-1H-pyrazol-4-yl)methylene)-2-thioxothiazolidin-4-one derivatives will be discussed in this study. Method: (Z)-5-((3-phenyl-1H-pyrazol-4-yl)methylene)-2-thioxothiazolidin-4-one derivatives were designed, synthesized and evaluated for antibacterial activity. The structures were confirmed by IR, 1H NMR, 13C NMR and mass spectrometry. All of the synthesized compounds were evaluated in vitro using a 96-well microtiter plate and a serial dilution method to obtain their minimum inhibitory concentration (MIC) values against a variety of different strains, including multidrug-resistant clinical isolates. Results: The antibacterial test in-vitro showed that most compounds in series 7 and 9 exhibited significant inhibitory activities against anaerobic bacteria (Streptococcus mutans) strains with a MIC value of 1 µg/mL. Compounds 7c and 9c showed the most potent activity against MRSA (3167 and 3506) with a minimum inhibitory concentration (MIC) value of 1 µg/mL, which is equivalent to moxifloxacin and greater than gatifloxacin, oxacillin and norfloxacin. Additionally, compound 9c showed potent antibacterial activity against Bacillus subtilis (aerobic bacteria) with a MIC value of 2 µg/mL. Conclusion: The work suggests that these type of rhodanine compounds had a better potent activity against MRSA compared with other perviously reported rhodanine derivatives, which might provide a valuable information for the development of new antibacterial agents against multidrug-resistant clinical isolates MRSA.

The transcription factor hypoxia-inducible factor-1α (HIF-1α) plays an important role in tumor angiogenesis, growth, and metastasis and is recognized as an important potential therapeutic target for cancer. Here, we designed and synthesized three novel series of ursolic acid derivatives containing an aminoguanidine moiety and evaluated them as HIF-1α inhibitors and anti-cancer agents using human cancer cell lines. Most of the compounds exhibited significant inhibition of HIF-1α transcriptional activity, as measured using a Hep3B cell-based luciferase reporter assay. Among these compounds, 7b was the most potent inhibitor of HIF-1α expression under hypoxic conditions (IC50 4.0 µM) and did not display significant cytotoxicity against any cell lines tested. The mechanism of action of 7b was investigated, we found that 7b downregulated HIF-1α protein expression, possibly by suppressing its synthesis, reduced production of vascular endothelial growth factor, and inhibited the proliferation of cancer cells.

The transforming growth factor-β (TGF-β), in which overexpression have been associated with various diseases, has become an attractive molecular target for the treatment of cancers. Three series of 3-substituted-4-(quinoxalin-6-yl) pyrazoles 14a–h, 15a–h, 16a–h, 22a, 22b, 22d, 23a, 23b, 23d, 24b, and 24d were synthesized and evaluated for their activin receptor-like kinase 5 (ALK5) and p38α mitogen activated protein (MAP) kinase inhibitory activity in an enzymatic assays. Among these compounds, the most active compound 16f inhibited ALK5 phosphorylation with an IC50 value of 0.28 µM, with 98% inhibition at 10 µM. Compound 16f also had good selectivity index of >35 against p38α MAP kinase, with 9.0-fold more selective than clinical candidate, compound 3 (LY-2157299). Molecular docking study was performed to identify the mechanism of action of the synthesized compounds and their good binding interactions were observed. ADMET prediction of good active compounds showed that these ones possess good pharmacokinetics and drug-likeness behavior.

Three series of 1,3-diaryl pyrazole derivatives bearing aminoguanidine or furan-2-carbohydrazide moieties have been synthesized, characterized and evaluated for antibacterial and anti-inflammatory activities. Most of the synthesized compounds showed potent inhibition of several Gram-positive bacterial strains (including multidrug-resistant clinical isolates) and Gram-negative bacterial strains with minimum inhibitory concentration values in the range of 1-64 μg/mL. Compounds 6g, 6l and 7l presented the most potent inhibitory activity against Gram-positive bacteria (e.g. Staphylococcus aureus 4220), Gram-negative bacteria (e.g. Escherichia coli 1924) and the fungus, Candida albicans 7535, with minimum inhibitory concentration values of 1 or 2 μg/mL. Compared with previous studies, these compounds exhibited a broad spectrum of inhibitory activity. Furthermore, compound 7l showed the greatest anti-inflammatory activity (93.59% inhibition, 30 min after intraperitoneal administration), which was more potent than the reference drugs ibuprofen and indomethacin.

An efficient method has been developed for the synthesis of a series of (20R)-panaxadiol derivatives (4a–w) using a continuous-flow microreactor. The antitumor activities of the newly synthesized compounds were evaluated in vitro in two human prostate adenocarcinoma tumor cell lines (i.e., PC-3 and LNCaP cells), and their cytotoxicities were evaluated using a standard MTT assay. Compounds 4c, 4h, 4p, 4q and 4s exhibited higher antitumor activities toward PC-3 cell line than panaxadiol, which was used as a reference standard.

Five series of dihydrotriazine derivatives containing chalcone (13a–i), phenoxy acetophenone (14a–b), benzyl benzene (15a–c), naphthoxyl acetophenone (16a–b) and benzyl naphthalene (17a–h) moieties were designed and synthesized. The antibacterial and antifungal activities of these compounds were evaluated against several strains of Gram-positive and Gram-negative bacteria, as well as a single fungus. Compound 17h was found to be the most potent of all of the compounds tested, with an MIC value of 0.5 μg/mL against several Gram-positive (Staphylococcus aureus 4220 and QRSA CCARM 3505) and Gram-negative (Escherichia coli 1924) strains of bacteria. However, this compound was inactive against Pseudomonas aeruginosa 2742 and Salmonella typhimurium 2421, indicating that its antibacterial spectrum is similar to those of the positive controls gatifloxacin and moxifloxacin. The cytotoxic activity of the compound 13i, 16b and 17h was assessed in Human normal liver cells.

Hypoxia-inducible factor-1α (HIF-1α), a key mediator in tumor metastasis and angiogenesis, is associated with poor patient prognosis and has been recognized as an important cancer drug target. In this work, four novel series of ursolic acid derivatives containing oxadiazole, triazolone, and piperazine moieties were designed, synthesized, and evaluated for anti-tumor activity as HIF-1α inhibitors. The majority of the compounds showed an excellent ability to inhibit the expression of HIF-1α. In particular, 11b inhibited HIF-1α transcriptional activity under hypoxic conditions with IC50=36.9μM. The cytotoxicity of these compounds was also assessed in human colon cancer cell HCT116 cells by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and no compounds showed any appreciable cytotoxic activity (IC50>100μmol/L), which was lower than that of ursolic acid (IC50=23.8μmol/L). The mechanism of action of the representative compound 11b was also investigated.

A series of new diarylpyrimidines (DAPYs) characterized by a halogen atom on the methylene linker between wing I and the central pyrimidine ring was synthesized and evaluated for their anti-HIV activity in MT-4 cell cultures. The two most promising compounds 7f and 7g showed excellent activity against wild-type HIV-1 with low nanomolar EC 50 values of 0.005 and 0.009 μM, respectively, which were comparable to or more potent than all the reference drugs zidovudine (AZT), lamivudine (3TC), nevirapine (NEV), efavirenz (EFV), delaviridine (DLV) and etravirine (ETV). In particular, 7g also displayed strong activity against the double mutant strain 103N + 181C with an EC 50 value of 8.2 μM. The preliminary structure–activity relationship (SAR) and molecular docking analysis of this new series of CHX-DAPYs were also investigated.

Two novel series of 3-((5-phenyl-1,3,4-oxadiazol-2-yl)methyl)-2-thioxothiazolidin-4-one derivatives were designed and synthesized, and their anti-bacterial activities evaluated. These compounds showed broad-spectrum inhibitory activities against both Gram-positive and Gram-negative bacteria with minimum inhibitory concentration (MIC) values in the range of 1–64 μg/mL. The activity of compound 6c was the more potent with MIC values of 1 μg/mL against the MRSA (3167 and 3506) strains than those of gatifloxacin, oxacillin, and norfloxacin. Compared to the previously reported rhodanine derivatives, 2-thioxothiazolidin-4-one derivatives exhibited an inhibition against Gram-negative strains due to the introduction of a 1,3,4-oxadiazole moiety, among which compounds 3 showed moderate activities against the Gram-negative bacteria (Escherichiacoli 1924) with MIC values of 16 μg/mL.

Three series of rhodanine derivatives bearing a quinoline moiety (6a-h, 7a-g, and 8a-e) have been synthesized, characterized, and evaluated as antibacterial agents. The majority of these compounds showed potent antibacterial activities against several different strains of Gram-positive bacteria, including multidrug-resistant clinical isolates. Of the compounds tested, 6g and 8c were identified as the most effective with minimum inhibitory concentration (MIC) values of 1 μg/mL against multidrug-resistant Gram-positive organisms, including methicillin-resistant and quinolone-resistant Staphylococcus aureus (MRSA and QRSA, respectively). None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL. The cytotoxic activity assay showed that compounds 6g, 7g and 8e exhibited in vitro antibacterial activity at non-cytotoxic concentrations. Thus, these studies suggest that rhodanine derivatives bearing a quinoline moiety are interesting scaffolds for the development of novel Gram-positive antibacterial agents.

Two series of furan derivatives bearing a rhodanine moiety (4a–l and 5a–l) have been synthesized, characterized, and evaluated for their antibacterial activity. The majority of these compounds showed potent levels of inhibitory activity against a variety of different Gram-positive bacteria, including multidrug-resistant clinical isolates, with minimum inhibitory concentration (MIC) values in the range of 2–16 μg/mL. In particular, compound 4l was found to be the most potent of the synthesized compounds against the multidrug-resistant strains, with a MIC value of 2 or 4 μg/mL. None of the compounds exhibited any activity against the Gram-negative bacteria Escherichia coli 1356 at 64 μg/mL. An examination of the cytotoxicities of these agents revealed that they displayed low levels of toxicity toward HeLa cells. All of the compounds synthesized in the current paper were characterized by 1H and 13C NMR, infrared, and mass spectroscopy. Two novel series of furan derivatives bearing a rhodanine moiety were synthesized, and evaluated for their antibacterial activity. Compounds 4l and 5a presented high potency against several multidrug-resistant clinical isolates.

In the current study, derivatives of 25-hydroxyprotopanaxadiol (25-OH-PPD) were prepared and their in vitro anti-tumor activities were tested on six different human tumor cell lines by standard MTT assay. The results showed that combining an ester group combined with the presence of an amino acid moiety led to a 10-fold improved anti-tumor activity. Compound 1c exhibited the best anti-tumor activity in the in vitro assays. Compounds 2c, 3c, 4c, 5c, 6c and 8b showed better anti-tumor activities compared to the parent compound 25-OH-PPD. The current results may provide useful data for researching and developing new anti-cancer agents.

A series of rhodanine-3-acetic acid derivatives were synthesized and investigated for their antibacterial activity against gram-positive bacteria including multidrug-resistant clinical isolates. Among these compounds, 6k with a MIC of 2 μg/mL was as active as the standard drug (norfloxacin) but less active than oxacillin against S. aureus. The compounds 6b, 6e, 6h, 6k, 6n, and 6u presented better activities against multidrug-resistant Staphylococcus aureus than the standard drugs (norfloxacin and oxacillin), especially 6k with a MIC of 1 μg/mL. However, none of the compounds were active against gram-negative bacteria at 64 μg/mL. This study presents a synthesis of novel rhodanine-3-acetic acid derivatives and their antibacterial activity.

Three novel series of chalcone derivatives containing an aminoguanidine or acylhydrazone moiety were designed, synthesized and evaluated in terms of their antibacterial, antifungal and anti-inflammatory activities. Most of the synthesized compounds showed potent inhibitory activity towards various bacteria and one fungus with minimum inhibitory concentrations (MICs) ranging from 1 to 8 μg/mL. Compared with our previously reported chalcone derivatives (MICs >64 μg/mL), these compounds exhibited improved antibacterial activities (MICs = 2 μg/mL) against Gram-negative bacterial strains (Escherichia coli 1924 and 1356). Compounds 4f and 4h were found to be the most potent with an MIC value of 1 μg/mL against the Gram-negative bacterial strains Salmonella typhimurium 1926 and the fungus Candida albicans 7535. In addition, compound 4f displayed the most potent anti-inflammatory activity of all of the compounds prepared in the current study with 92.45% inhibition after intraperitoneal administration, making it more potent than the reference drugs indomethacin and ibuprofen. The cytotoxic activity of the compound 4f was assessed in HeLa, Hep3B and L02 cells.

In this study, four novel series of 4-phenyl-1H-1,2,4-triazol-5(4H)-one derivatives containing triazole or piperazine moieties were designed, synthesized, and evaluated for negative inotropic activity by measuring the left atrium stroke volume in isolated rabbit heart preparations. Almost all of the compounds showed an ability to moderate the cardiac workload by decreasing the heart rate and contractility. Among them, 7h was found to be the most potent with a change in stroke volume of -48.22 ± 0.36% at a concentration of 3 × 10-5 mol/L (metoprolol: -9.74 ± 0.14%). The cytotoxicity of these compounds was evaluated using the human cervical cancer cell line HeLa, the liver cancer cell line Hep3B, and the human normal hepatic cell line LO2. A preliminary study of the mechanism of action for the compound 7h on the regulation of atrial dynamics with ATP-sensitive K+ channel and L-type Ca2+ channel blockers glibenclamide and nifedipine was performed in the isolated perfused beating rabbit atria.

We describe the synthesis and positive inotropic evaluation of a series of 2-(4-substitutedbenzylpiperazin-1-yl)-N-(2-oxo-2,3-dihydrobenzooxazol-6-yl)acetamides by measuring left atrial stroke volume in preparations of isolated rabbit hearts. Several compounds were developed from and showed favorable activities compared with the standard drug milrinone. Compound 4l was the most potent with an increased stroke volume of 11.78 ± 0.18% (milrinone 6.36 ± 0.13%) at 1 × 10(-4) M in our in-vitro study. The chronotropic effects of compounds having inotropic effects were also evaluated.

A series of 2,4,6-trihydroxychalcone derivatives were synthesized and identified as reversible and competitive protein tyrosine phosphatase (PTP) 1B inhibitors with IC50 values in the micromolar range. Compound 4a had the greatest in vitro inhibition activity against PTP1B (IC50 = 0.27 ± 0.01 μm) and the best selectivity (6.9-fold) for PTP1B relative to T-cell protein tyrosine phosphatases. The compounds identified herein provide a foundation on which to design specific inhibitors of PTP1B and other PTPs.

Protein tyrosine phosphatase 1B (PTP1B) is a key factor in negative regulation of the insulin pathway, and is a promising target for the treatment of type-II diabetes, obesity and cancer. Herein, compound () was first observed to have moderate inhibitory activity against PTP1B with an value of . To obtain more potent PTP1B inhibitors, we synthesized a series of chalcone derivatives using compound () as the lead compound. Compound () was 4.4-fold more potent than the lead compound (), and more potent than the positive control, ursolic acid (). These results may help to provide suitable drug-like lead compounds for the design of inhibitors of PTP1B as well as other PTPs.