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A spectrophotometric assay was developed for the quantification of peroxidase activity in the presence of para -phenylenediamine dihydrochloride (PPDD) and 8-hydroxyquinolene (8-HQ) as chromogenic co-substrates in KH 2 PO 4 /NaOH buffer solution at pH 7.8. The resulting violet coloured product had maximum absorbance at 540 nm. Under optimized condition, the linearity range of hydrogen peroxide (H 2 O 2 ) was 1–124 µM and that of peroxidase was 0.2958–14 nM and 0.0739–2.3674 nM by kinetic and fixed time assays, respectively. The Michaelis–Menten ( K m ) constant, catalytic efficiency and catalytic power were 38.72 µM, 0.2613 × 10 6 M −1 min −1 and 2.4748 × 10 −3 min −1 , respectively. The obtained broad and sensitive linearity range of H 2 O 2 and peroxidase assays and lower value of Michaelis–Menten constant indicate the superiority of this method. The developed method was successfully applied to study the effect of blanching treatment of peroxidase in sapota and fig fruit extracts and this is helpful in fixing blanching temperature and blanching time for fruits.

A series of curcumin pyrazole derivatives (3a–e) were synthesized. The chemical structures were determined by 1H and 13C NMR spectroscopic techniques and their purity was confirmed by LC–MS and melting point determination. The compounds were screened for anticancer effects on different cancer cell lines by MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay. The analogs demonstrated growth inhibitory effect on MCF-7, HeLa, and K562 cell lines with significant IC50 values. Compound 3b exhibited a high degree of cytotoxicity against cancer cells and minimum growth inhibitory effects against normal cells HEK293T and hence further, cell cycle analysis and mitochondrial membrane potential studies (JC-1 assay) were conducted by utilizing flow cytometry against K562 cells. This compound effectively arrested cell cycle progression at SubG1 phase and cells exhibited decreased membrane potential in a concentration-dependent manner with fluorescence shifting from red to green. Our findings suggest that compound 3b could be a promising anticancer agent since it effectively inhibited cell proliferation and can be selected for further in vitro and in vivo investigations.

Persistent activation of signal transducer and activator of transcription 3 (STAT3) is associated with the progression of a range of tumors. In this report, we present the anticancer activity of 2-(1-(4-(2-cyanophenyl)1-benzyl‑1H-indol-3-yl)-5-(4-methoxy-phenyl)-1-oxa-3-azaspiro(5,5)undecane (CIMO) against breast cancer cells. We observed that CIMO suppresses the proliferation of both estrogen receptor-negative (ER-) (BT-549, MDA-MB‑231) and estrogen receptor-positive (ER+) (MCF-7, and BT-474) breast cancer (BC) cells with IC50 of 3.05, 3.41, 4.12 and 4.19 µM, respectively, and without significantly affecting the viability of normal cells. CIMO was observed to mediate its anti-proliferative effect in ER- BC cells by inhibiting the phosphorylation of JAK2 and STAT3 proteins. Quantitative PCR analysis demonstrated that CIMO decreases the relative mRNA expression of genes that are involved in cell cycle progression (CCND1) and cell survival (BCL2, BCL-xL, BAD, CASP 3/7/9, and TP53). In addition, CIMO was observed to arrest BC cells at G0/G1 phase and of the cell cycle. Furthermore, CIMO suppressed BC cell migration and invasion with concordant regulation of genes involved in epithelial to mesechymal transition (CDH1, CDH2, OCLN and VIM). Thus, we report the utility of a synthetic azaspirane which targets the JAK-STAT pathway in ER- BC.

In this report, we describe the synthesis of 1-(Phthalazin-4-yl)-hydrazine using bronsted acidic ionic liquids and demonstrate their ability to inhibit asexual stage development of human malaria parasite, Plasmodium falciparum. Through computational studies, we short-listed chemical scaffolds with potential binding affinity to an essential parasite protein, dihydroorotate dehydrogenase (DHODH). Further, these compounds were synthesized in the lab and tested against P. falciparum. Several compounds from our library showed inhibitory activity at low micro-molar concentrations with minimal cytotoxic effects. These results indicate the potential of hydralazine derivatives as reference scaffolds to develop novel antimalarials.

Cancer is a multifactorial disease, which makes it difficult to cure. Since more than one defective cellular component is often involved during oncogenesis, combination therapy is gaining prominence in the field of cancer therapeutics.The purpose of this study was to investigate the combinatorial effects of a novel PARP inhibitor, P10, and HDAC inhibitor, SAHA, in leukemic cells.Combinatorial effects of P10 and SAHA were tested using propidium iodide staining in different leukemic cells. Further, flowcytometry-based assays such as calcein-AM/ethidium homodimer staining, annexin-FITC/PI staining, and JC-1 staining were carried out to elucidate the mechanism of cell death. In addition, cell-cycle analysis, immunocytochemistry studies, and western blotting analysis were conducted to check the combinatorial effect in Nalm6 cells.Propidium iodide staining showed that P10 in combination with SAHA induced cell death in Nalm6 cells, in which PARP expression and activity is high with a combination index of0.2. Annexin-FITC/PI staining, JC-1 staining, and other biochemical assays revealed that P10 in combination with SAHA induced apoptosis by causing a change in mitochondrial membrane potential in65 % cells. Importantly, combinatorial treatment induced S phase arrest in 40-45 % cells due to DNA damage and plausible replicative stress. Finally, we demonstrated that treatment with P10 led to DNA strand breaks, which were further potentiated by SAHA (p 0.01), leading to activation of apoptosis and increased cell death in PARP-positive leukemic cells.Our study reveals that coadministration of PARP inhibitor with SAHA could be used as a combination therapy against leukemic cells that possess high levels of intrinsic PARP activity.

A new modified van Leusen strategy has been developed for the synthesis of biologically significant 5-substituted oxazoles by the reaction of (het)aryl methyl alcohols or benzyl bromides as precursors with tosylmethylisocyanide (TosMIC) under basic conditions. This method is efficient, takes place under mild reaction conditions, and is tolerant of various functional groups with high yield.

In this study, we report the one-pot synthesis of substituted carbazole derivatives using nano cuprous oxide as a catalyst via intramolecular C–N bond forming reactions. Among the synthesized carbazoles, 3′-((3-acetyl-6-chloro-9H-carbazol-9-yl)methyl)-[1,1′-biphenyl]-2-carbonitrile (ACB) was identified as a lead antiproliferative agent against lung cancer cell lines A549 and LLC with an IC50 of 13.6 and 16.4 μM respectively. Furthermore, we found that the lead compound suppresses the constitutive phosphorylation of STAT3 (Tyr-705) in A549, HCC-2279 and H1975 cells. We analyzed the levels of phospho-STAT3 and LSD1 in the nuclear extract of ACB treated HCC-2279 cells to evaluate the transcriptional activity of STAT3. We found the downregulation of phospho-STAT3 without any change in the expression of LSD1 indicating that ACB downregulates the transcriptional activity of STAT3. Molecular docking analysis revealed that ACB makes a favorable interaction with Arg-609 and Ser-613 in the pTyr site of the SH2 domain of STAT3.

A new approach for the synthesis of novel bis(imidazol-1-yl)vinyl-1,2,4-oxadiazoles has been developed. This method operates in a single step giving the products in good to excellent yields. Antiproliferative efficiency of the synthesized compounds was tested against HCT116 (colon cancer) and A549 (lung cancer) cell lines. Among them, compounds 3m (IC50, 9.7 μM) and 3h (IC50, 20.3 μM) were found to be the best antiproliferative agents.

Iodine-mediated synthesis of 3-sulfenylimidazo[1,5-a]pyridines via C–H functionalization has been achieved using dithioesters, 2-methylaminopyridines and sulfonyl hydrazides. A library of 3-sulfanylimidazopyridines and imidazopyridines with broad functionalities are synthesized under metal-free reaction conditions.

Herein, the transition-metal-free economical solid phase synthesis of 1,2-disubstituted 4-quinolones has been developed via the novel regiospecific synthesis of enaminones. Notably, a wide range of enaminones were synthesized via a silica-supported solid-phase reaction in good to excellent yields. The transformation of enaminones to 1,2-disubstituted 4-quinolones and N-methyl-2-aryl-4-quinolone alkaloid was achieved in high yield via an alumina-supported solid phase reaction. In addition, all the synthesized compounds were isolated directly in their pure form from the reaction mixture using an easy workup procedure.

T3P–DMSO mediated desulfurative cyclization of in situ generated thioamides serves as an efficient and versatile method for the synthesis of imidazo[1,5-a]pyridines and [1,2,4]-triazolo[4,3-a]pyridines with good to excellent yields. Substrates such as 2-methylaminoquinoline and pyrazin-2-yl-methanamine also undergo the corresponding reactions at room temperature. This efficient protocol has several advantages such as mild conditions, short reaction time, operational simplicity and high yields.

Carbon nanotubes (CNTs), due to their van der Waals forces and π–π interaction, have great potential as a strong material resource for environmental water purification. Herein, we reported the purification of industrial effluent using polyvinyl alcohol (PVA) and multiwall carbon nanotube (MWCNT) composite materials. It is demonstrated that the removal of methyl red dye and heavy metals can be driven simultaneously by using efficient composite materials. The methyl red dye present in an aqueous solution of effluent formed hydrogen bonds with PVA polymers and adsorbed, simultaneously, the heavy metals also adsorbed on the cylindrical hollow structure of MWCNTs and removed them. The environmentally friendly removal of dye and heavy metals was confirmed by scanning electron microscopy, chemical oxygen demand tests, X-ray diffraction and UV-visible spectrophotometry.

An efficient and ecofriendly protocol for the N-alkylation of secondary heterocyclic amines such as 10H-phenothiazine, 5H-dibenzo[b,f]azepine, 9H-carbazole and 2-butyl-4-chloro-1H-imidazole-5-carbaldehyde by various alkyl halides such as allyl bromide, propargyl bromide, methyl iodide and 4-methylbenzyl chloride in Glucose-Urea-NaCl and Glucose-Urea-NH4Cl eutectic mixture has been reported. High yield (73-94%) and short reaction time are the noteworthy features of this protocol.

This data in brief article explains the anti-cancer activity and characterization of oxadiazoles [1]. The main objective of this article was to provide general synthetic procedures, spectral discussion and physical data on the new oxadiazole tethered indazole (OTDs). This article discusses the 1H NMR, 13C NMR, mass spectroscopy, HPLC and melting point of the synthetic compounds. MTT assay was used to determine the anti-proliferative activity in hepatocellular cell lines.

Liquid crystal (LC) is an intermediate phase of matter with the physical attributes of liquid, and a high-level of orientational order of solids. This property of LCs has been widely utilized for the development of LC displays and other industrial applications. The research in the past few decades shows the substantial increase in the exploring of applications of five-membered liquid crystalline heterocycles in photovoltaic devices, organic light-emitting technologies, and biological systems. In this article, we have discussed the history, classification, synthetic strategies, physical parameters and mesomorphic studies of five-membered heterocycles beyond biological applications. The liquid crystalline heterocycles that are covered in the review include imidazoles, isoxazoles, isoxazolines, pyrazoles, pyrazolines, thiazoles, thiophenes, 1,2,3- and 1,2,4-triazoles, 1,2,4- and 1,3,4-oxadiazoles, and 1,3,4-thiadiazoles. Overall, the review provides a comprehensive profile of the mesomorphic properties of five-membered heterocycles.

An efficient method for the synthesis of 4-tosyl-5-aryloxazoles directly from aromatic carboxylic acids has been reported. The method involves the conversion of aromatic carboxylic acids to tosyl carboxylates by treating with tosyl chloride in the presence of potassium carbonate and its subsequent reaction with tosylmethyl isocyanide in the presence of sodium hydride to get 4-tosyl-5-aryloxazoles. 4, 5 di-substituted oxazoles were synthesized via an efficient method directly from aromatic carboxylic acids. The presented method involves the conversion of aromatic carboxylic acids to tosyl carboxylates by treating with tosyl chloride in the presence of potassium carbonate and its subsequent reaction with tosylmethyl isocyanide in the presence of sodium hydride yielding 4-tosyl-5-aryloxazoles.

Human BCL-2–associated death promoter (hBAD) is an apoptosis-regulatory protein mediating survival signals to carcinoma cells upon phosphorylation of Ser99, among other residues. Herein, we screened multiple small-molecule databases queried in a Laplacian-modified naive Bayesian-based cheminformatics platform and identified a Petasis reaction product as a site-specific inhibitor for hBAD phosphorylation. Based on apoptotic efficacy against mammary carcinoma cells, N-cyclopentyl-3-((4-(2,3-dichlorophenyl) piperazin-1-yl) (2-hydroxyphenyl) methyl) benzamide (NPB) was identified as a potential lead compound. In vitro biochemical analyses demonstrated that NPB inhibited the phosphorylation of hBAD specifically on Ser99. NPB was observed to exert this effect independently of AKT and other kinase activities despite the demonstration of AKT-mediated BAD-Ser99 phosphorylation. Using a structure-based bioinformatics platform, we observed that NPB exhibited predicted interactions with hBAD in silico and verified the same by direct binding kinetics. NPB reduced phosphorylation of BAD-Ser99 and enhanced caspase 3/7 activity with associated loss of cell viability in various human cancer cell lines derived from mammary, endometrial, ovarian, hepatocellular, colon, prostatic, and pancreatic carcinoma. Furthermore, by use of a xenograft model, it was observed that NPB, as a single agent, markedly diminished BAD phosphorylation in tumor tissue and significantly inhibited tumor growth. Similar doses of NPB utilized in acute toxicity studies in mice did not exhibit significant effects. Hence, we report a site-specific inhibitor of BAD phosphorylation with efficacy in tumor models.

The search for improved therapeutic approaches to breast cancer are still on going. Breast tumor kinase (BRK, also known as PTK6) is one of the targets, it is highly expressed in breast carcinomas while displaying low or no expression in the normal mammary gland, which hints at the oncogenic role of this enzyme in breast cancer. In these twenty years, an increasing number of studies have focused on understanding the cellular roles of BRK in breast cancers. This review outlines the advances made towards understanding the cellular and physiological role of BRK, the molecular and chemical inhibitors and its therapeutic significance in breast cancer.

The formation of a thrombus is a key event in thromboembolic disorders, that contribute to high mortality and morbidity in affected patients. In the present study, we synthesized a library of novel substituted 3,3-dibutyl-8-methoxy-2,3-dihydrobenzo [b] [1,4] thiazepin-4(5H)-one derivatives which were tested for their platelet aggregation and thrombin inhibitory activity. Among the tested compounds, 3,3-dibutyl-7-(2-chlorophenyl)-8-methoxy-2,3-dihydrobenzo[b] [1,4]thiazepin-4(5H)-one (DCT) displayed the maximum thrombin inhibition with an IC50 value of 3.85 μM and thus DCT was chosen for further studies. Next, the effect of DCT on primary hemostasis was evaluated using agonist-induced platelet aggregation model. The lead compound inhibited the collagen- or ADP- or thrombin-induced platelet aggregation in a dose-dependent manner. Furthermore, DCT prolonged the process of clot formation when evaluating plasma re-calcification time (320 ± 11 sec at 5 µg DCT), activated partial thromboplastin time (58.0 ± 0.01 sec at 2 µg), and prothrombin time (14.7 ± 0.01 sec at 5 µg). Molecular docking studies suggested that the benzothiazepinones evaluated here consistently display hydrogen bonding with Ser214 of thrombin, which is similar to that of the co-crystallized ligand (1-(2R)-2-amino-3-phenyl-propanoyl-N-(2,5dichlorophenyl)methylpyrrolidine-2-carboxamide). DCT displayed additional hydrogen bonding to Ser195 and π-π interactions between its methoxyphenyl groups and Trp60, thereby providing a structural rationale for the observed biological effect.

Aberrant expression of estrogen receptor alpha (ER-α) is observed in many pathological complications like breast cancer, endometrial cancer, and in osteoporosis. ER-α plays a vital role in the initiation and progression of breast cancer and confers chemo and radioresistance to the cancer cells by upregulating expression of anti-apoptotic proteins. The synthetic pyrazole derivative 3-(1-(4-bromophenyl)-5-phenyl-1H-pyrazol-3-yl)pyridine (compound 5d) displays significant cytotoxicity against mammary carcinoma cells. Molecular docking studies revealed that compound 5d binds to ligand binding domain of (ER-α). In vivo studies were carried out to investigate ER-α expression by immunohistochemistry and quantitative RT-PCR, which revealed reduction of ER-α in tumor cells upon treatment with compound 5d indicating its ER-α antagonistic effect. Our study ascertains compound 5d as a potent inhibitor of mammary carcinoma cells.

Myelination delay and remyelination failure following insults to the central nervous system (CNS) impede axonal conduction and lead to motor, sensory and cognitive impairments. Both myelination and remyelination are often inhibited or delayed due to the failure of oligodendrocyte progenitor cells (OPCs) to mature into myelinating oligodendrocytes (OLs). Digestion products of the glycosaminoglycan hyaluronan (HA) have been implicated in blocking OPC maturation, but how these digestion products are generated is unclear. We tested the possibility that hyaluronidase activity is directly linked to the inhibition of OPC maturation by developing a novel modified flavonoid that functions as a hyaluronidase inhibitor. This compound, called S3, blocks some but not all hyaluronidases and only inhibits matrix metalloproteinase activity at high concentrations. We find that S3 reverses HA-mediated inhibition of OPC maturation in vitro, an effect that can be overcome by excess recombinant hyaluronidase. Furthermore, we find that hyaluronidase inhibition by S3 accelerates OPC maturation in an in vitro model of perinatal white matter injury. Finally, blocking hyaluronidase activity with S3 promotes functional remyelination in mice with lysolecithin-induced demyelinating corpus callosum lesions. All together, these findings support the notion that hyaluronidase activity originating from OPCs in CNS lesions is sufficient to prevent OPC maturation, which delays myelination or blocks remyelination. These data also indicate that modified flavonoids can act as selective inhibitors of hyaluronidase activity and can promote OPC maturation, making them excellent candidates to accelerate myelination or promote remyelination following perinatal and adult CNS insults.

Background: Tuberculosis is one of the top ranked airborne infectious diseases caused by the bacillus Mycobacterium tuberculosis with high mortality rate from a single infectious agent. In the present article, we aimed to synthesize oxadiazole-coumarin-triazole based small molecules and evaluate for their possible anti-mycobacterial activity. Method: Herein, we describe the facile synthesis of 5-((1H-benzo[d][1,2,3]triazol-1-yl)methyl)-1,3,4- oxadiazole-2-thiol-tethered substituted 4-(bromomethyl)-7-methyl-2H-chromen-2-one derivatives and evaluated for their anti-mycobacterial activity against H37Rv strain of M. tuberculosis. We also evaluated the cytotoxic effect of new compounds on normal cells. Results: Among the 14 novel oxadiazole-coumarin-triazole derivatives, 4-((5-((1H-benzo[d][1,2,3]triazol-1- yl)methyl)-1,3,4-oxadiazol-2-ylthio)methyl)-6-methoxy-2H-chromen-2-one (5f) displayed good antimycobacterial activity towards M. tuberculosis with an MIC value of 15.5 µM. Pyrazinamide was used as reference drug. Our investigation also revealed that, 5f is not cytotoxic to normal cells. Conclusion: In summary, the findings suggested that novel 1,3,4-oxadiazole coumarin-triazole hybrids are promising antimycobacterial agents against M. tuberculosis.

The products of arachidonic acid metabolism by lipoxygenase (LOX) and cyclooxygenase (COX) significantly contribute to inflammation and carcinogenesis. Particularly, overproduction of leukotrienes and prostaglandins contribute to tumor growth by inducing formation of new blood vessels that sustain tumor cell viability and growth. Hence, search for novel anticancer drug via inhibition of LOX and COX enzymes constitutes an impressive strategy till date. In this context, a series of isoxazole derivatives were synthesized and screened for their anti-inflammatory activity via LOX and COX inhibition. Among these, 3-(3-methylthiophen-2-yl)-5-(3,4,5-trimethoxyphenyl)isoxazole (2b) showed significant inhibitory activity toward LOX and COX-2. Additionally, 2b showed a good inhibition of tumor growth, peritoneal angiogenesis, and ascite formation in Ehrlich ascites carcinoma (EAC) cell mouse model. Further, the in silico molecular studies also revealed that the compound 2b binds to the catalytic domain of LOX and COX-1 and COX-2 strongly with high atomic contact energy (ACE) score compared to standard drug. These initial pharmacological data support the fact that the compound 2b serves as the basis in developing anti-inflammatory and anticancer agents.

4-Thiazolidinone derivatives were synthesized using T3P (R)-DMSO media as a cyclodehydrating agent. All the molecules were tested for their cytotoxicity against leukemic cell lines. The compound 3-(4-bromophenyl)-2-(4-(dimethylamino)phenyl)thiazolidin-4-one (4e) with electron donating substituent at para position of phenyl ring displayed considerable cytotoxicity against Reh and Nalm6 cells with an IC50 value of 11.9 and 13.5 mu M, respectively. Furthermore, the compound 4e tested for tumor regression studies induced by EAC in Swiss albino mouse. Both in vitro and in vivo results suggested significant antiproliferative activity of compound 4e in Reh cells and mouse tumor tissue treated with compound 4e showed multifocal areas of necrosis and numerous number of apoptotic cells. (C) 2015 Elsevier Ltd. All rights reserved.

The first cross-coupling reaction between aryl/heteroaryl pentafluorobenzenesulfonates and aryl/heteroaryl boronic acids under mild conditions is described. The successful synthesis of highly ortho substituted biaryls and high chemoselectivity of these bench stable intermediates over tosylates, triflates, mesylates, and chlorides increases its scope as a valuable cross-coupling partner. The generality of this protocol was further extended to other boron containing nucleophiles (boronates, trifluoroborates) and alkyl boronic acids.

An efficient methodology for the synthesis of 2,3-disubstituted 3H-quinazolin-4-ones is described via one-pot three component reaction from anthranilic acid using T3P as catalyst. Mild reaction conditions, short reaction time, broad functional group tolerance, easy isolation of products and good yields are main advantages of this protocol.

Malaria caused by the Plasmodium parasites continues to be an enormous global health problem owing to wide spread drug resistance of parasites to many of the available antimalarial drugs. Therefore, development of new classes of antimalarial agents is essential to effectively treat malaria. In this study, the efficacy of naturally occurring diterpenoids, dehydroabietylamine and abietic acid, and their synthetic derivatives was assessed for antimalarial activity. Dehydroabietylamine and its N-trifluoroacetyl, N-tribromoacetyl, N-benzoyl, and N-benzyl derivatives showed excellent activity against P. falciparum parasites with IC50 values of 0.36 to 2.6 µM. Interestingly, N-dehydroabietylbenzamide showed potent antimalarial activity (IC50 0.36), and negligible cytotoxicity (IC50 >100 µM) to mammalian cells; thus, this compound can be an important antimalarial drug. In contrast, abietic acid was only marginally effective, exhibiting an IC50 value of ~82 µM. Several carboxylic group-derivatives of abietic acid were moderately active with IC50 values of ~8.2 to ~13.3 µM. These results suggest that a detailed understanding of the structure–activity relationship of abietane diterpenoids might provide strategies to exploit this class of compounds for malaria treatment.

Due to the toxic pathophysiological role of snake venom phospholipase A2 (PLA2 ), its compelling limitations to anti-venom therapy in humans and the need for alternative therapy foster considerable pharmacological interest towards search of PLA2 specific inhibitors. In this study, an integrated approach involving homology modeling, molecular dynamics and molecular docking studies on VRV-PL-V (Vipera russellii venom phospholipase A2 fraction-V) belonging to Group II-B secretory PLA2 from Daboia russelli pulchella is carried out in order to study the structure-based inhibitor design. The accuracy of the model was validated using multiple computational approaches. The molecular docking study of this protein was undertaken using different classes of experimentally proven, structurally diverse synthetic inhibitors of secretory PLA2 whose selection is based on IC50 value that ranges from 25 μM to 100 μM. Estimation of protein-ligand contacts by docking analysis sheds light on the importance of His 47 and Asp 48 within the VRV-PL-V binding pocket as key residue for hydrogen bond interaction with ligands. Our virtual analysis revealed that compounds with different scaffold binds to the same active site region. ADME analysis was also further performed to filter and identify the best potential specific inhibitor against VRV-PL-V. Additionally, the e-pharmacophore was generated for the best potential specific inhibitor against VRV-PL-V and reported here. The present study should therefore play a guiding role in the experimental design of VRV-PL-V inhibitors that may provide better therapeutic molecular models for PLA2 recognition and anti-ophidian activity.

The title compound [1-(3,5-Dimethyl-2,3-dihydro-isoxazole-4-sulfonyl)-piperidin-4-yl)-diphenyl-methanol was synthesized and the product obtained was characterized by spectroscopic techniques and finally the structure was confirmed by X-ray diffraction studies. The compound crystallizes in the monoclinic crystal system with the space group P21/c and with unit cell parameters a = 8.5280(6) A, b = 25.223(4) A, c = 10.7060(17) A, β = 99.879(8)°, and Z = 4. The structure reveals that the piperidine ring is in chair conformation. The geometry around the S atom is distorted tetrahedral. The structure exhibits both inter- and intramolecular hydrogen bonds of the type O—H···N and C—H···O.

An efficient ligand- and catalyst-free intramolecular S-arylation leading to the direct synthesis of indalothiochromen-4-ones from simple dithioesters under mild conditions has been developed. This method is particularly noteworthy given its experimental simplicity, high generality, and good functional group toleration.

Cancer is a leading cause of death in developed countries and second cause in developing countries. Herein we are reporting the synthesis of novel bisbenzimidazole derivatives and their anticancer properties. Among the newly synthesized bisbenzimidazoles, 3-(4-flurophenylsulfonyl)-1,7-dimethyl-2-propyl-1H,3H-2,5-bibenzo[d]imidazole (FDPB) presented as a potent antiproliferative agent against HeLa, HCT116 and A549 cells with selectivity over normal Vero cells (IC50 >50 μM). Additionally, we evaluated the efficacy of lead compound against Ehrlich ascites tumor (EAT) bearing mice for its antitumor and antiangiogenic properties. Our lead compound significantly reduced the cell viability, body weight, ascites volume and downregulated the formation of neovasculature and production of Vascular Endothelial Growth Factor (VEGF).

Hepatocellular carcinoma (HCC) is the fifth most common malignant tumor worldwide, and is the third most common cause of cancer related death. Constitutive activation of NF-κB is the underlying mechanism behind tumorigenesis and this protein regulates the expression of genes involved in proliferation, survival, drug resistance, angiogenesis and metastasis. The design of inhibitors which suppress NF-κB activation is therefore of great therapeutic importance in the treatment of HCC. In this study, we investigated the effect of newly synthesized coumarin derivatives against HCC cells, and identified (7-Carbethoxyamino-2-oxo-2H-chromen-4-yl)methylpyrrolidine-1 carbodithioate (CPP) as lead compound. Further, we evaluated the effect of CPP on the DNA binding ability of NF-κB, CXCL12-induced cell migration and invasion, and the regulated gene products in HCC cells. We found that CPP induced cytotoxicity in three HCC cells in a time and dose dependent manner, and suppressed the DNA binding ability of NF-κB. CPP significantly decreased the CXCL12-induced cell migration and invasion. More evidently, CPP inhibits the expression of NF-κB targeted genes such as cyclin D1, Bcl-2, survivin, MMP12 and C-Myc. Furthermore, the molecular docking analysis suggested that CPP interacts with the p50 binding domain of the p65 subunit, scoring best among the 26 docked coumarin derivatives of this study. Thus, we are reporting CPP as a potent inhibitor of the pro-inflammatory pathway in Hepatocellular carcinoma.

The first one pot protocol for the diastereoselective synthesis of oxazolo[2,3-c]isoquinoline was achieved by a metal-free, benzoic acid catalyzed reaction of 1,2,3,4-tetrahydroisoquinoline or trypoline with aldehydes under mild conditions via C–H, C–O bond functionalization. A new approach for the synthesis of highly substituted 1H-pyrrolo[2,1-c][1,4]oxazine was carried out.

Synthesis of polycyclic amines was achieved by benzoic acid catalysed reaction of 1-aryl THIQs and 1-aryl trypolines with o-allyl salicylaldehydes through the in situ generated azomethine ylide intermediates that undergo intramolecular [3+2]-cycloadditions with four new stereogenic centers in excellent diastereoselectivities under simple and mild conditions.

Phospholipase A2 (PLA2) is known to regulate inflammation and hence it is considered as a validated drug-target by medicinal chemists. In this report, we have identified and considered a highly ranked ligand from the ZINC-drug-like compounds database that targets PLA2 via the MOLPRINT-2D based chemoinformatics drug-design approach. The computationally predicted lead molecule was found to contain a core moiety of a chromene ring, which is well known for its varied biological properties. Here, a novel and efficient retro-synthetic protocol for the synthesis of highly substituted chromene libraries was made. A one-pot synthesis of chromene was carried out using different aromatic primary alcohols, malononitrile and 4-hydroxy coumarin in the presence of a mild oxidant mixture called T3P®–DMSO, followed by a Suzuki coupling reaction to obtain the lead molecules. All of the tested compounds of the chromene series displayed inhibition of the venom PLA2 in the range of 12 to 68 μM. Among the tested compounds, 2-amino-4-(2′-methyl-[1,1′-biphenyl]-4-yl)-5-oxo-4,5-dihydropyrano[3,2-c]chromene-3-carbonitrile (7b) showed maximum inhibitory efficacy against venom PLA2 with an IC50 value of 12.5 μM. Furthermore, the designed PLA2 ligands bound to the active site of venom PLA2, whose binding affinity was comparable to nimesulide, indicating that the chromene moiety containing ligands could be novel lead-structures that serve as anti-inflammatory agents.

Elevated activity of methionyl-tRNA synthetase (MRS) in many cancers renders it a possible drug target in this disease area, as well as in a series of parasitic diseases. In the present work, we report the synthesis and in vitro screening of a library of 1,3-oxazines, benzoxazines and quinoline scaffolds against human MRS. Among the compounds tested, 2-(2-butyl-4-chloro-1-(4-phenoxybenzyl)-1H-imidazol-5-yl)-5-(4-methoxyphenyl)-1-oxa-3-azaspiro[5.5]undecane (compound 21) and 2-(2-butyl-4-chloro-1-(4-nitrobenzyl)-1H-imidazol-5-yl)-2,4-dihydro-1H-benzo[d][1,3]oxazine (compound 8) were found to be potent inhibitors of MRS. Additionally, these compounds significantly suppressed the proliferation of A549 and HCT116 cells with IC50 values of 28.4, 17.7, 41.9, and 19.8 μM respectively. Molecular docking studies suggested that the ligand binding orientation overlaps with the original positions of both methionine and adenosine of MRS. This suggests the binding of compound 21 against MRS, which might lead the inhibitory activity towards cancer cells.

Malaria, a complex and deadly parasitic infectious disease, is a huge public health problem in many endemic countries around the globe. The prevailing extensive resistance of malaria parasites to traditional drugs and emergence of resistance to the currently used frontline artemisinin-based chemotherapy calls for the development of new drugs. Towards this objective and since compounds containing the dibenzazepine moiety are effective in treating both gametocyte and asexual stage malaria parasites, including multi drug resistant parasites, a library of dibenzazepine tethered 3,5-disubstituted isoxazolines was synthesised via 1,3-dipolar cycloaddition reaction. An additional diversified group of dibenzazepine derivatives were accessed by Suzuki coupling of one of the above dibenzazepine derivatives with various organoboronic acids. All compounds were structurally characterized and were evaluated for their antimalarial activity. They exhibited good to excellent inhibitory activity against the growth of drug-sensitive Plasmodium falciparum 3D7 strain with IC50 values ranging from 0.2 to 7.7 μM. About 50% of the compounds were either minimally or not toxic to human cell lines. Five of the compounds (6j, 6k, 8c, 8k and 8l) that highly inhibited the parasite growth were further assessed for antimalarial activity using an additional chloroquine-sensitive (D6) and two chloroquine-resistant (W2 and 7G8) P. falciparum strains. These compounds were effective against all four strains (3D7, D6, W2 and 7G8), exhibiting IC50 values of 0.1 to 1.75 μM. The dibenzazepines were identified to target the metalloamino-peptidase of parasites. Molecular docking and dynamics simulation studies were performed to understand the binding mode and binding strengths of the selected compounds with the enzyme. In agreement with their excellent antimalarial activity, the data suggested that the compounds can strongly bind to the active site of the enzyme.

A series of 2,4,5-trisubstituted imidazoles and 1,2-disubstituted benzimidazoles catalyzed by ZrO2-supported-β-cyclodextrin (ZrO2-β-CD) under solvent free conditions have been synthesized and characterized by spectral methods. The nanoparticles (ZrO2-β-CD), prepared by a simple one-pot-coprecipitation method and were characterized by PXRD, SEM, and TEM techniques. The nano (ZrO2-β-CD) particles were found to be an effective heterogeneous reusable catalyst for the effective synthesis of imidazoles and benzimidazoles under solvent free conditions and all of the synthesized derivatives were evaluated for their antibacterial activity against six bacterial strains.

DNA minor groove binders are an important class of chemotherapeutic agents. These small molecule inhibitors interfere with various cellular processes like DNA replication and transcription. Several benzimidazole derivatives showed affinity towards the DNA minor groove. In this study we show the synthesis and biological studies of a novel benzimidazole derivative (MH1), that inhibits topoisomerase II activity and in vitro transcription. UV-visible and fluorescence spectroscopic methods in conjunction with Hoechst displacement assay demonstrate that MH1 binds to DNA at the minor groove. Cytotoxic studies showed that leukemic cells are more sensitive to MH1 compared to cancer cells of epithelial origin. Further, we find that MH1 treatment leads to cell cycle arrest at G2/M, at early time points in Molt4 cells. Finally multiple cellular assays demonstrate that MH1 treatment leads to reduction in MMP, induction of apoptosis by activating CASPASE 9 and CASPASE 3. Thus our study shows MH1, a novel DNA minor groove binder, induces cytotoxicity efficiently in leukemic cells by activating the intrinsic pathway of apoptosis.

Efficient synthesis of benzo[b]thiophenes from o-halophenyl acetonitrile has been achieved. This novel one-pot procedure involves CuI and pivalic acid catalyzed C–S bond formation using dithioesters followed by a heterocyclization reaction. This efficient protocol has the advantages of one-pot synthesis, short reaction time, good yields (62–78%) and operational simplicity.

Chronic hyperglycemia is one of the characteristic conditions associated with Diabetes Mellitus (DM), which often exerts deleterious effects on erythrocyte morphology and hemodynamic properties leading to anemia and diabetes-associated vascular complications. High glucose-induced over production of reactive oxygen species (ROS) can alter the blood cell metabolism and biochemical functions subsequently causing eryptosis (red blood cell death), yet another complication of concern in DM. Therefore, blocking high glucose-induced oxidative damage and subsequent eryptosis is of high importance in the better management of DM and associated vascular complications. In this study, we synthesized an oxolane derivative 1-(2,2-dimethyltetrahydrofuro[2,3][1,3]dioxol-5-yl)ethane-1,2-diol (DMTD), and demonstrated its efficacy to mitigate hyperglycemia-induced ROS generation and subsequent eryptosis. We showed that DMTD effectively inhibits high glucose-induced ROS generation, intracellular calcium levels, phosphaditylserine (PS) scrambling, calpain and band 3 activation, LDH leakage, protein glycation and lipid peroxidation, meanwhile enhances the antioxidant indices, osmotic fragility and Na+/K+-ATPase activity in erythrocytes. DMTD dose dependently decreased the glycated hemoglobin level and enhances the glucose utilization by erythrocytes in vitro. Further, DMTD alleviated the increase in ROS production, intracellular Ca2 + level and PS externalization in the erythrocytes of human diabetic subjects and enhanced the Na+/K+-ATPase activity. Taken together, the synthesized oxolane derivative DMTD could be a novel synthetic inhibitor of high glucose-induced oxidative stress and eryptosis. Considering the present results DMTD could be a potential therapeutic to treat DM and associated complications and open new avenues in developing synthetic therapeutic targeting of DM-associated complications.

Background Expression and activity of heparanase, an endoglycosidase that cleaves heparan sulfate (HS) side chains of proteoglycans, is associated with progression and poor prognosis of many cancers which makes it an attractive drug target in cancer therapeutics. Methods In the present work, we report the in vitro screening of a library of 150 small molecules with the scaffold bearing quinolones, oxazines, benzoxazines, isoxazoli(di)nes, pyrimidinones, quinolines, benzoxazines, and 4-thiazolidinones, thiadiazolo[3,2-a]pyrimidin-5-one, 1,2,4-triazolo-1,3,4-thiadiazoles, and azaspiranes against the enzymatic activity of human heparanase. The identified lead compounds were evaluated for their heparanase-inhibiting activity using sulfate [35S] labeled extracellular matrix (ECM) deposited by cultured endothelial cells. Further, anti-invasive efficacy of lead compound was evaluated against hepatocellular carcinoma (HepG2) and Lewis lung carcinoma (LLC) cells. Results Among the 150 compounds screened, we identified 1,2,4-triazolo-1,3,4-thiadiazoles bearing compounds to possess human heparanase inhibitory activity. Further analysis revealed 2,4-Diiodo-6-(3-phenyl-[1, 2, 4]triazolo[3,4-b][1, 3, 4]thiadiazol-6yl)phenol (DTP) as the most potent inhibitor of heparanase enzymatic activity among the tested compounds. The inhibitory efficacy was demonstrated by a colorimetric assay and further validated by measuring the release of radioactive heparan sulfate degradation fragments from [35S] labeled extracellular matrix. Additionally, lead compound significantly suppressed migration and invasion of LLC and HepG2 cells with IC50 value of ~5 μM. Furthermore, molecular docking analysis revealed a favourable interaction of triazolo-thiadiazole backbone with Asn-224 and Asp-62 of the enzyme. Conclusions Overall, we identified biologically active heparanase inhibitor which could serve as a lead structure in developing compounds that target heparanase in cancer. Electronic supplementary material The online version of this article (doi:10.1186/s12885-017-3214-8) contains supplementary material, which is available to authorized users.

Background: Identification of breast cancer stem cells as the chemo-resistant and tumor-initiating population represents an important milestone in approaching anticancer therapies. Targeting this minor subpopulation of chemo- and radio-resistant stem-like cells, termed as the cancer stem cells (CSCs) and their eradication could significantly enhance clinical outcomes. Most of the presently administered chemotherapeutics target the tumor bulk but are ineffective against the CSCs. We report here that diosgenin (DG), a naturally occurring steroidal saponin, could effectively inhibit CSCs from three breast cancer cell lines, MCF7, T47D and MDA-MB-231, by inducing apoptosis and inhibiting the CSC associated phenotypes. Methods: CSCs were enriched in these cells lines, characterized for CSC traits by immunocytochemistry and flow cytometry. Proliferation and apoptosis assays were performed in these breast CSCs in the presence of DG to obtain the inhibitory concentration. Apoptosis was confirmed with gene expression analysis, Western blotting and propidium iodide staining. TCF-LEF reporter assay, sFRP overexpression and RNAi silencing studies were performed to study regulation of the Wnt pathway. Statistical significance was evaluated by a two-sided Student’s t test. Results: Using the TCF-LEF reporter system, we show the effect of DG on CSCs is predominantly through the network regulating CSC self renewal, the Wnt s-catenin pathway. Specifically, the Wnt antagonist, the secreted frizzled related protein 4, (sFRP4), had a defining role in the action of DG. Gain-of-function of sFRP4 in CSCs could improve the response to DG wherein CSC mediators were inhibited, s-catenin was down regulated and the effectors of epithelial to mesenchymal transition (EMT) and pro-invasive markers were repressed. Conversely, the loss-of-function of sFRP4 had a reverse effect on the CSC population which therein became enriched, their response to DG treatment was modest, s-catenin levels increased, GSK3s expression decreased and the expression of epithelial markers of CSC was completely abrogated. Conclusions: These findings demonstrate the effect of DG on inhibiting the resilient breast CSCs which could provide a benchmark for the development of diosgenin-based therapies in breast cancer treatment.

Cholinesterase plays a vital role in the decline of cholinergic transmission and thus can contribute to the development of Alzheimer’s disease (AD). Thus, compounds that can inhibit acetylcholinesterase (AChe) and butyrylcholinesterase (BuChe) are the potential drugs for the treatment of AD. A series of novel pyrrolopyrimidine derivatives was synthesized and evaluated for their inhibitory activity against cholinesterase by Ellman method. Among the ten newly synthesized compounds, 4-(4-((4-(difluoromethoxy)phenyl)amino)-7H-pyrrolo[2,3-d]pyrimidin-6-yl)benzoate was the most potent molecule identified with the IC50 values of 18 µM and 17 µM on AChe and BuChe respectively.

Secretory phospholipases A2 (sPLA2s) are present in snake venoms, serum, and biological fluids of patients with various inflammatory, autoimmune and allergic disorders. Lipid mediators in the inflammatory processes have potential value for controlling phospholipid metabolism through sPLA2 inhibition. Thus, it demands the need for screening of potential leads for sPLA2 inhibition. To date, sPLA2 activity has been assayed using expensive radioactive or chromogenic substrates, thereby limiting a large number of assays. In this study, a simple and sensitive NanoDrop assay was developed using non-fluorogenic and non-chromogenic phospholipid substrate 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 8-anilino-1-naphthalenesulfonic acid (ANS) as interfacial hydrophobic probe. The modified assay required a 10ng concentration of sPLA2. ANS, as a strong anion, binds predominantly to cationic group of choline head of DMPC through ion pair formation, imparting hydrophobicity and lipophilicity and resulting in an increase in fluorescence. Triton X-100 imparts correct geometrical space during sPLA2 catalyzing DMPC, releasing lysophospholipid and acidic myristoyl acid, which in turn alters the hydrophobic environment prevailing around ANS–DMPC, which leads to weakening of the electrostatic ion pair interaction between DMPC and ANS ensuing decrease in fluorescence. These characteristic fluorescence changes between DMPC and ANS in response to sPLA2 catalysis are well documented and validated in this study.

An efficient and rapid four component reaction of aldehydes, malanonitrile, β-ketoesters and hydrazine hydrate (or phenyl hydrazine) in environmentally benign room temperature ionic liquid choline chloride-urea has been developed for the synthesis of substituted 4H-pyrano[2,3-c]pyrazoles.

A series of benzisoxazole derivatives were synthesized and evaluated for their antibacterial, antioxidant and anti-inflammatory activities. The results indicated that most of the compounds exhibit moderate antimicrobial activity against Gram negative ( Escherichia coli , Klebsiella pneumoniae , Salmonella typhi , Shigella flexineri ) and Gram positive ( Bacillus subtilis ) bacterial culture. The molecules were evaluated for antioxidant activities using 2,2-diphenyl-1-picrylhydrazyl scavenging, super oxide radical scavenging and hydroxyl radical scavenging assays and most of them showed good antioxidant activities. Also, the synthesized compounds were screened for anti-inflammatory activities such as lipoxygenase inhibition and indirect haemolytic assays.

A facile, convenient, and multicomponent coupling strategy for the synthesis of highly functionalized pyrroles is developed using graphite as a catalyst, but devoid of moisture-sensitive metal catalysts and corrosive acidic reagents. This method involves four-component coupling reactions of ethyl acetoacetate compound or diethyl acetylene dicarboxylate, amines, aromatic aldehydes, and nitromethane without an inert atmosphere. This approach provides easy access to highly substituted pyrroles in good yields via one-pot tandem reaction. The method is very simple, straightforward, and environmentally friendly compared to the existing methods. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]

Four nickel complexes with β-(oximinoalkyl)amine ligands OxnHn containing one (Ox1H1), two (Ox2H2), four (Ox4H4) and six (Ox6H6) oxime groups were synthesized and characterized by elemental analysis, FTIR, HRMS and single crystal X-ray diffraction. β-Oximinoalkylamines OxnHn act as polydentate ligands forming five-membered chelate rings, in which nickel is coordinated with both amine and oxime nitrogen atoms. In all structurally characterized complexes, OH-groups of oximes arms are involved in hydrogen bonding with counterions (Cl−), which are located in the inner or outer coordination sphere of the nickel atom. Two new structural types of pseudo-octahedral Ni(II) β-oximinoalkylamine complexes containing two ligands per one nickel ion (Ni(Ox1H1)2Cl2 and Ni(Ox2H2)2Cl2) were identified. Dioxygen reactivity of the obtained complexes in aerobic oxidation of triphenylphosphine was studied. Bis-oxime complex Ni(Ox2H2)2Cl2 was found to be the most active promoter of triphenylphosphine oxidation among the synthesized nickel complexes.

The kinetics of the ruthenium(III) chloride [Ru(III)]-catalysed oxidation of four α-amino acids (AA) viz. glycine (Gly), valine (Val), alanine (Ala) and leucine (Leu) by sodium N-chloro-p-toluenesulfonamide (CAT: Chloramine-T) in the presence of hydrochloric acid medium has been studied at 308 K. The oxidation reaction follows the identical kinetics for all the four amino acids and obeys the rate law, rate = k ′ [ CAT ] o [ S ] o x [ H + ] y [ Ru ( III ) ] , where x and y are fractions. Variation of ionic strength of the medium, addition of the halide ions and the reaction product (PTS: p-toluenesulfonamide) show negligible effect on rate of the reaction. Solvent composition shows positive effect indicating that positive ion-dipolar molecule involved in the rate determining step. The oxidation products were identified. The activation parameters have been evaluated from the Arrhenius plots. The activation energy values are least for the fastest reactions and vice versa. The large negative value of ΔS‡ and the high value of ΔG‡ support the proposed mechanism. Under comparable experimental conditions, the rate of oxidation of amino acids increases in the order: Leu > Ala > Val > Gly. This trend may be attributed to hydrophobicity, nucleophilicity and inductive effect of amino acids. The reaction mechanism and the derived rate law are consistent with the observed experimental results.