Design, Synthesis, Computational Studies, and Anti-Proliferative Evaluation of Novel Ethacrynic Acid Derivatives Containing Nitrogen Heterocycle, Urea, and Thiourea Moieties as Anticancer Agents.

In the present work, the synthesis of new ethacrynic acid () derivatives containing nitrogen heterocyclic, urea, or thiourea moieties via efficient and practical synthetic procedures was reported. The synthesised compounds were screened for their anti-proliferative activity against two different cancer cell lines, namely, HL60 (promyelocytic leukaemia) and HCT116 (human colon carcinoma). The results of the in vitro tests reveal that compounds -, , (-), and exhibit potent anti-proliferative activity against the HL60 cell line, with values of the percentage of cell viability ranging from 20 to 35% at 1 μM of the drug and IC values between 2.

β-arrestin biased signaling is not involved in the hypotensive actions of 5-HT receptor stimulation: use of Serodolin.

The 5-hydroxytryptamine 7 receptor (5-HT) is necessary for 5-HT to cause a concentration-dependent vascular relaxation and hypotension. 5-HT is recognized as having biased signaling, transduced through either Gs or β -arrestin. It is unknown whether 5-HT signals in a biased manner to cause vasorelaxation/hypotension.

Improvement of the Chemical Reactivity of Michael Acceptor of Ethacrynic Acid Correlates with Antiproliferative Activities.

The present study aims to report the design, synthesis, and biological activity of new ethacrynic acid () analogs () obtained by the double modulation of the carboxylic acid moiety and the aromatic ring with the aim to increase the chemical reactivity of Michael acceptor of . All obtained compounds were characterized by H and C NMR, IR, and high-resolution mass spectrometry. The antiproliferative activity was evaluated in vitro using MMT test, in a first step, against HL60 cell line and in a second step, on a panel of human cancer cell lines such as HCT116, A549, MCF7, PC3, U87-MG, and SKOV3, and normal cell line MRC5 in comparison with positive control doxorubicin.

Development and preclinical evaluation of [F]FBVM as a new potent PET tracer for vesicular acetylcholine transporter.

Age-related neurodegenerative diseases have in common the occurrence of cognitive impairment, a highly incapacitating process that involves the cholinergic neurotransmission system. The vesicular acetylcholine transporter (VAChT) positron emission tomography (PET) tracer [F]fluoroethoxybenzovesamicol ((-)-[F]FEOBV) has recently demonstrated its high value to detect alterations of the cholinergic system in Alzheimer's disease, Parkinson's disease and dementia with Lewy body. We present here the development of the new vesamicol derivative tracer (-)-(R,R)-5-[F]fluorobenzovesamicol ((-)[F]FBVM) that we compared to (-)[F]FEOBV in the same experimental conditions.

Synthesis, Photophysical Properties, and Aromaticity of Pyrazine-Fused Tetrazapentalenes.

Pyrazine-fused 1,2,6,6a-tetrazapentalenes (PyTeAP) are zwitterionic tricyclic compounds exhibiting an original pattern with four consecutive nitrogen atoms. They were obtained by a challenging cyclization through the formation of a N-N bond under thermolytic conditions. Ten derivatives were synthesized, and the original scaffold of PyTeAP was confirmed by single-crystal X-ray diffraction analysis of one derivative.

Synthesis, Anticancer Activities and Molecular Docking Studies of a Novel Class of 2-Phenyl-5,6,7,8-tetrahydroimidazo [1,2-]pyridazine Derivatives Bearing Sulfonamides.

In the present study, new 2-phenyl-5,6,7,8-tetrahydroimidazo [1,2-]pyridazines bearing sulfonamides were synthesized, characterized and evaluated for their anticancer activities. The structures of these derivatives were elucidated by H NMR, C NMR, infrared and high-resolution mass spectrometry for further validation of the target compound structures. The anticancer activities of the new molecules were evaluated against five human cancer cell lines, including A-549, Hs-683, MCF-7, SK-MEL-28 and B16-F10 cell lines using 5-fluorouracil and etoposide as the reference drugs.

Inhibition of Metastasis by Polypyridyl Ru(II) Complexes through Modification of Cancer Cell Adhesion - Functional and Molecular Studies.

The effect of polypyridyl Ru(II) complexes on the ability of cancer cells to migrate and invade, two features important in the formation of metastases, is evaluated. studies are carried out on breast cancer cell lines, MDA-MB-231 and MCF-7, as well as melanoma cell lines A2058 and A375. Three Ru(II) complexes comprising two 4,7-diphenyl-1,10-phenanthroline (dip) ligands and as a third ligand 2,2'-bipyridine (bpy), or its derivative with either 4-[3-(2-nitro-1H-imidazol-1-yl)propyl] (bpy-NitroIm), or 5-(4-{4'-methyl-[2,2'-bipyridine]-4-yl}but-1-yn-1-yl)pyridine-2-carbaldehyde semicarbazone (bpy-SC) moiety attached are examined.

Impact of Polypyridyl Ru Complexes on Angiogenesis-Contribution to Their Antimetastatic Activity.

The use of polypyridyl Ru complexes to inhibit metastasis is a novel approach, and recent studies have shown promising results. We have reported recently that Ru (II) complexes gathering two 4,7-diphenyl-1,10-phenanthroline (dip) ligands and the one being 2,2'-bipyridine (bpy) or its derivative with a 4-[3-(2-nitro-1H-imidazol-1-yl)propyl (bpy-NitroIm) or 5-(4-{4'-methyl-[2,2'-bipyridine]-4-yl}but-1-yn-1-yl)pyridine-2-carbaldehyde semicarbazone (bpy-SC) moieties can alter the metastatic cascade, among others, by modulating cell adhesion properties. In this work, we show further studies of this group of complexes by evaluating their effect on HMEC-1 endothelial cells.

Serodolin, a β-arrestin-biased ligand of 5-HT receptor, attenuates pain-related behaviors.

G protein–coupled receptors (GPCRs) are involved in regulation of manifold physiological processes through coupling to heterotrimeric G proteins upon ligand stimulation. Classical therapeutically active drugs simultaneously initiate several downstream signaling pathways, whereas biased ligands, which stabilize subsets of receptor conformations, elicit more selective signaling. This concept of functional selectivity of a ligand has emerged as an interesting property for the development of new therapeutic molecules.

Access and modulation of substituted 1-methyl-1,6-dihydropyrazolo[3,4-]pyrazoles.

Despite the pharmacological potential of the pyrazolo[3,4-]pyrazoles, only a few methods of preparation and direct functionalization of this moiety have been described. We report herein a convenient design of new pyrazolo[3,4-]pyrazoles with a high therapeutic impact. The effective chosen strategy consists of hydrazine condensations and C-N Ullmann-type cross-coupling reactions with microwave activation.

Near-Infrared Emitting Poly(amidoamine) Dendrimers with an Anthraquinone Core toward Versatile Non-Invasive Biological Imaging.

Today, there is a very strong demand for versatile near-infrared (NIR) imaging agents suitable for non-invasive optical imaging in living organisms ( imaging). Here, we created a family of NIR-emitting macromolecules that take advantage of the unique structure of dendrimers. In contrast to existing fluorescent dendrimers bearing fluorophores at their periphery or in their cavities, a NIR fluorescent structure is incorporated into the core of the dendrimer.

Synthesis and evaluation of a novel class of ethacrynic acid derivatives containing triazoles as potent anticancer agents.

For unmet clinical needs, a novel class of ethacrynic acid (EA) derivatives containing triazole moieties (3a-i and 8) were designed, synthesized and evaluated as new anticancer agents. The in vitro anti-proliferative activities were assessed first on HL60 cell line and in a second stage, the two selected compounds 3a and 3c were tested on a panel of human cancer cell lines (A549, MCF7, PC3, U87-MG, SKOV3 and HCT116) and on a normal cell line (MCR5). Compound3c exhibited very good antitumor activities with IC values of 20.

Pyridazino-1,3a,6a-Triazapentalenes as Versatile Fluorescent Probes: Impact of Their Post-Functionalization and Application for Cellular Imaging.

Pyridazino-1,3a,6a-triazapentalenes (PyTAP) are compact fused 6/5/5 tricyclic scaffolds which exhibit promising fluorescent properties. Chemically stable, they can be post-functionalized using standard Pd-catalyzed cross-coupling chemistry. Several original PyTAP bearing additional unsaturated substituents in positions 2 and 8 were synthetized and their spectroscopic properties analyzed.

Synthesis and biological evaluation of ethacrynic acid derivatives bearing sulfonamides as potent anti-cancer agents.

A series of ethacrynic acid (2-[2,3-dichloro-4-(2-methylidenebutanoyl)phenoxy]acetic acid) (EA, Edecrin) containing sulfonamides linked via three types of linkers namely 1,2-ethylenediamine, piperazine and 4-aminopiperidine was synthesized and subsequently evaluated in vitro against HL60 and HCT116 cancer cell lines. All the EA analogs, excluding 6a and 6c, showed anti-proliferative activity with IC in the micromolar range (less than 4 uM). Three derivatives 6b, 7b and 7e were selected for their interesting dual activity on HL60 cell line in order to be further evaluated against a panel of cancer cell lines (HCT116, A549, MCF7, PC3, U87-MG and SKOV3) as well as on MRC5 as a normal cell line.

"On Water" Palladium Catalyzed Direct Arylation of 1Indazole and 1-7-Azaindazole.

The C3 direct arylation of 1-indazole and 1-7-azaindazole has been a significant challenge due to the lack of the reactivity at this position. In this paper, we describe a mild and an efficient synthesis of new series of C3-aryled 1-indazoles and C3-aryled 1-7-azaindazoles via a C3 direct arylation using water as solvent. On water, PPh was effective as a ligand along with a lower charge of the catalyst Pd(OAc) (5 mol%) at 100 °C, leading to C3-aryled 1-indazoles or C3-aryled 1-7-azaindazoles in moderate to good yields.

Intramolecular Metal-Free N-N Bond Formation with Heteroaromatic Amines: Mild Access to Fused-Triazapentalene Derivatives.

Formation of N-N bonds may offer an original approach to various nitrogen-containing heterocycles with numerous applications. For this purpose, we found that readily available heteroaromatic amines are appropriate substrates for providing an efficient and innovative approach for the formation of N-N bonds in the presence of iodine (III) reagent in very mild conditions. This method makes it possible to synthesize nitrogen rich triazapentalene derivatives exhibiting fluorescent properties, inaccessible with existing approaches.

Bis(het)aryl-1,2,3-triazole quinuclidines as α7 nicotinic acetylcholine receptor ligands: Synthesis, structure affinity relationships, agonism activity, [F]-radiolabeling and PET study in rats.

In this paper we describe the design and synthesis of bis(Het)Aryl-1,2,3-triazole quinuclidine α7R ligands using an efficient three-step sequence including a Suzuki-Miyaura cross coupling reaction with commercially available and home-made boron derivatives. The exploration of SAR required the preparation of uncommon boron derivatives. Forty final drugs were tested for their ability to bind the target and nine of them exhibited Ki values below nanomolar concentrations.

An original class of small sized molecules as versatile fluorescent probes for cellular imaging.

An unusual class, compact in size, of fluorescent probes based on pyridazino-1,3a,6a-triazapentalene scaffolds exhibits promising fluorescent properties (quantum yield values up to 73%, large Stokes shifts, emission wavelengths located in the green-yellow range, excellent solubility) with good photostability suitable for optical imaging applications.

Organocatalytic aza-Michael Reaction to 3-Vinyl-1,2,4-triazines as a Valuable Bifunctional Platform.

An unprecedented catalytic aza-Michael addition to substituted 3-vinyl-1,2,4-triazines, as original bifunctional platforms for the domino conjugate addition inverse-electron-demand hetero-Diels-Alder/retro-Diels-Alder ( ihDA/ rDA) reaction, was achieved using the highly acidic triflimide as an organocatalyst. Based on the use of alkoxyamine nucleophiles, this sequence not only highlights a rare example of the catalytic aza-Michael reaction to alkenylazaarenes but also proves to be useful for the elaboration of an array of biorelevant tetrahydro-[1,6]-naphthyridines.

Palladium-Catalyzed C3-Arylations of 1 H- and 2 H-Pyrazolo[4,3- b]pyridines on Water.

Direct C3-arylation of 1 H-pyrazolo[4,3- b]pyridines and direct C3-arylation of 2 H-pyrazolo[4,3- b]pyridines in water has been developed. A new protocol for a sequential C3-arylation procedure on a mixture of 1 H- and 2 H-pyrazolo[4,3- b]pyridines followed by in situ PMB cleavage has also been achieved. This procedure led to unprotected ( NH) C3-arylated 1 H-pyrazolo[4,3- b]pyridines in good yields.

Access to 1H-indazoles, 1H-benzoindazoles and 1H-azaindazoles from (het)aryl azides: a one-pot Staudinger-aza-Wittig reaction leading to N-N bond formation?

The synthesis of various substituted 1H-indazoles is reported through N-N bond formation from an iminophosphorane derivative. Supported by control experiments, an original Staudinger-aza-Wittig tandem mechanism is proposed for this transformation.

A Novel Polyaminocarboxylate Compound To Treat Murine Pulmonary Aspergillosis by Interfering with Zinc Metabolism.

can cause pulmonary aspergillosis in immunocompromised patients and is associated with a high mortality rate due to a lack of reliable treatment options. This opportunistic pathogen requires zinc in order to grow and cause disease. Novel compounds that interfere with fungal zinc metabolism may therefore be of therapeutic interest.

Efficient synthesis and first regioselective C-6 direct arylation of imidazo[2,1-c][1,2,4]triazine scaffold and their evaluation in HO-induced oxidative stress.

Oxidative stress and apoptosis are both associated with various acute and chronic disorders. Thus, the aim of the present study is to synthesize imidazo[2,1-c][1,2,4]triazines derivatives and to evaluate their effects in HO-induced oxidative stress in human neuroblastoma cell line (SH-SY5Y cells). The effects of the compounds on cell viability were measured by MTT assay and the changes in stress and apoptosis-related proteins were investigated by PathScan Stress and Apoptosis Signaling Antibody Array kit and Western Blot technique.

"On Water" Direct C-3 Arylation of 2H-Pyrazolo[3,4-b]pyridines.

An "on water" palladium-catalyzed direct (hetero)arylation of 2H-pyrazolo[3,4-b]pyridines has been developed. The reactions proceeds smoothly with at low catalytic loading at low temperature providing the C3 (hetero)arylated products in good to excellent isolated yields. Free NH 3-arylated 7-azaindazoles were also prepared by simple cleavage of the N-protected groups.

Dual role of mitochondria in producing melatonin and driving GPCR signaling to block cytochrome c release.

G protein-coupled receptors (GPCRs) are classically characterized as cell-surface receptors transmitting extracellular signals into cells. Here we show that central components of a GPCR signaling system comprised of the melatonin type 1 receptor (MT), its associated G protein, and β-arrestins are on and within neuronal mitochondria. We discovered that the ligand melatonin is exclusively synthesized in the mitochondrial matrix and released by the organelle activating the mitochondrial MT signal-transduction pathway inhibiting stress-mediated cytochrome release and caspase activation.