Piperazine squaric acid diamides, a novel class of allosteric P2X7 receptor antagonists.

The P2X7 receptor (P2X7R) stands out among the purinergic receptors due to its strong involvement in the regulation of tumor growth and metastasis formation as well as in innate immune responses and afferent signal transmission. Numerous studies have pointed out the beneficial effects of P2X7R antagonism for the treatment of a variety of cancer types, inflammatory diseases, and chronic pain. Herein we describe the development of novel P2X7R antagonists, incorporating piperazine squaric diamides as a central element. Besides improving the antagonists' potency from pIC50 values of 5.7-7.6, ADME properties (logD7.4 value, plasma protein binding, in vitro metabolic stability) of the generated compounds were investigated and optimized to provide novel P2X7R antagonists with drug-like properties. Furthermore, docking studies revealed the antagonists binding to the allosteric binding pocket in two distinct binding poses, depending on the substitution of the central piperazine moiety.

Synthesis and Properties of Pentafluorosulfanyl Group (SF5)-Containing Meta-Diamide Insecticides.

Herein, we describe novel pentafluorosulfanyl (SF5) group-containing meta-diamide insecticides. For the facile preparation of the SF5-based compounds 4a-d, practical synthetic methods were applied. Among newly synthesized compounds, 3-benzamido-N-(2,6-dimethyl-4-(pentafluoro-λ6-sulfanyl)phenyl)-2-fluorobenzamide 4d showed (i) a high insecticidal activity, (ii) an excellent selectivity to insects, and (iii) good levels of water solubility and log P values. In this study, we demonstrated that the pentafluorosulfanyl moiety could serve as an attractive functionality for the discovery of a new scope of crop-protecting agents.

SAR study of bisamides as cyclophilin a inhibitors for the development of host-targeting therapy for hepatitis C virus infection.

The therapy of chronic hepatitis C virus infections has significantly improved with the development of direct-acting antivirals (DAAs), which contain NS3/4A protease, NS5A, and NS5B polymerase inhibitors. However, mutations in specific residues in these viral target genes are associated with resistance to the DAAs. Especially inhibitors of NS3/4A protease and NS5A, such as grazoprevir and velpatasvir, have a low barrier to resistant mutations. As a result, the mutations influence the virological outcomes after DAA treatment. CypA inhibitors, as host-targeted agents, act on host factors to inhibit HCV replication, exhibiting a high resistance barrier and pan-genotype activities against HCV. Therefore, they can be developed into alternative, more effective anti-HCV agents. However, CypA inhibitors are natural products and analogs. Based on previous studies, bisamide derivatives were designed and synthesized to develop a novel class of CypA inhibitors. Bisamide derivative 7c is a promising compound with potent anti-HCV activity at subtoxic concentrations. Surface plasmon resonance experiments revealed that 7c directly binds to CypA. All these studies indicated that the derivative 7c is a potent CypA inhibitor, which can be used as a host-targeted agent in combination with other antiviral agents for anti-HCV treatment.

The discovery of diazetidinyl diamides as potent and reversible inhibitors of monoacylglycerol lipase (MAGL).

Monoacylglycerol lipase (MAGL) has emerged as an attractive drug target because of its important role in regulating the endocannabinoid 2-arachidonoylglycerol (2-AG) and its hydrolysis product arachidonic acid (AA) in the brain. Herein, we report the discovery of a novel series of diazetidinyl diamide compounds 6 and 10 as potent reversible MAGL inhibitors. In addition to demonstrating potent MAGL inhibitory activity in the enzyme assay, the thiazole substituted diazetidinyl diamides 6d-l and compounds 10 were also effective at increasing 2-AG levels in a brain 2-AG accumulation assay in homogenized rat brain. Furthermore, selected compounds have been shown to achieve good brain penetration after oral administration in an animal study.

Sulfonimidamides and Imidosulfuric Diamides: Compounds from an Underexplored Part of Biologically Relevant Chemical Space.

Two novel solid reagents-1-sulfonimidoyl- and 1-sulfamimidoyl-3-methylimidazolium derivatives-for the synthesis of sulfonimidamides and imidosulfuric diamides, respectively, were developed. It is shown that these reagents are very effective in substitution reactions with various N- and O-nucleophiles; therefore, they significantly extend the accessibility to the chemical space covered by organosulfur(VI) compounds with S=N bonds. In addition, previously unknown imidosulfuric diamides with free imino nitrogen groups were prepared, and their physical and chemical properties were characterized (including molecular geometry, pKa , Log P, microsomal stability, and reactivity towards typical electrophiles). Similar to other organosulfur(VI) derivatives with S=N bonds, these compounds can be considered as promising bioisosteres of amides, ureas, or sulfonamides.

Synthesis and insecticidal activity study of novel anthranilic diamides analogs containing a diacylhydrazine bridge as effective Ca2+ modulators.

Anthranilic diamides is a class of insecticides target at ryanodine receptors (RyRs). To discover potent insecticides targeting at RyRs, a series of novel anthranilic diamides with a diacylhydrazine bridge were designed and synthesized. Their insecticidal activities were evaluated and a preliminary structure-activity relationship (SAR) was summarized. In particular, compound 5g exhibited good lethality against oriental armyworm (Mythimna separata) at a concentration of 5 mg/L. The calcium imaging experimental results indicated that the compound 5g can serve as effective insect Ca2+ level modulators by disrupting the cellular calcium homeostasis in Mythimna separata (Walker) and Spodoptera exigua (Hübner), which probably activated the RyRs on the ER membrane.

Anthranilic diamides derivatives as potential ryanodine receptor modulators: Synthesis, biological evaluation and structure activity relationship.

A series of novel anthranilic diamides derivatives (7a-s) containing halogen, trifluoromethyl group and cyano group were designed, synthesized, and characterized by melting point, 1H NMR, 13C NMR and elemental analyses. The bioactivity revealed that most of them showed moderate to excellent activities against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella). Above all, the larvicidal activity of 7o against oriental armyworm was 100% and 40% at 0.25 and 0.1 mg L-1, comparable to that of the standard chlorantraniliprole (100%, 0.25 mg L-1 and 20%, 0.1 mg L-1). What is more, 7o against diamondback moth displayed 90% insecticidal activity at 0.01 mg L-1, superior to chlorantraniliprole (45%, 0.01 mg L-1). The experiments 7o on the American cockroach (Periplaneta Americana) heart beating rates (Dorsal vessel) and contractile force were compared with chlorantraniliprole. In addition, 7o could affect the calcium homeostasis in the central neurons of the third larvae of oriental armyworm, which revealed that the ryanodine receptor is the potential target of 7o. The density functional theory (DFT) calculation results revealed the amide bridge, the benzene ring of anthraniloyl moiety and pyrazole ring might play an important role in the insecticidal activity through hydrophobic interactions and π-π conjugations.

Seeded Polymerization through the Interplay of Folding and Aggregation of an Amino-Acid-based Diamide.

Amino acid based diamides are widely used as a substructure in supramolecular polymers and are also key components of polypeptides that help to understand protein folding. The interplay of folding and aggregation of a diamide was used to achieve seed-initiated supramolecular polymerization. For that purpose, a pyrene-substituted diamide was synthesized in which pyrene is used as a tracer to monitor the supramolecular polymerization. Thermodynamics and time-dependent studies revealed that the folding of the diamide moiety, via the formation of intramolecular hydrogen bonds, effectively prevents a spontaneous nucleation that leads to supramolecular polymerization. Under such out-of-equilibrium conditions, the addition of seeds successfully initiates the supramolecular polymerization. These results demonstrate the utility of such amino acid based diamides in programmable supramolecular polymerizations.

Synthesis and cardiomyocyte protection activity of crocetin diamide derivatives.

A series of novel diamide derivatives (2-8) of crocetin (1) were synthesized and evaluated for their cardioprotective activity in vitro. Using well-established model of hypoxia-induced injury in H9c2 cells, we investigated the effects of 9 compounds and positive drug nicorandil on cellular cytotoxicity by MTT assay, mitochondrial viable staining, LDH activity and mitochondrial membrane potential (MMP). Among the new derivatives, compounds 3 and 4 with good liposolubility showed significantly potent activity than crocetin (1) against hypoxia-induced cytotoxicity. Further mechanisms studies indicated that the cardioprotective effect of compounds 3 and 4 was due to these abilities by decreasing LDH release, preserving mitochondrial viabilities and reducing oxidative stress-induced depolarization of MMP. Our results demonstrated that compounds 3 and 4 as a new class of crocetin diamide derivatives could be developed as potential agents in our further drug development studies for ischemic heart disease.

Structure-based bioisosterism design, synthesis, insecticidal activity and structure-activity relationship (SAR) of anthranilic diamide analogues containing 1,2,4-oxadiazole rings.

BACKGROUND: Anthranilic diamide derivatives are among the most important classes of synthetic insecticides. Moreover, the 1,2,4-oxadiazole heterocycle, a bioisostere of amide, has been extensively used in pesticides. In order to discover novel molecules with high insecticidal activities, a series of anthranilic diamide analogues containing 1,2,4-oxadiazole rings were designed and synthesised. RESULTS: A series of novel anthranilic diamide derivatives containing 1,2,4-oxadiazole were obtained, and confirmed by 1 H and 13 C nuclear magnetic resonance and high-resolution mass spectrometry. The structure of 3-bromo-N-(4-chloro-2-methyl-6-{3-[(methylsulphonyl)methyl]-1,2,4-oxadiazol-5-yl}phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide was further characterised by X-ray diffraction analysis. In addition, bioassays showed that most of the newly synthesised compounds displayed 100% mortality against Plutella xylostella at 100 mg L-1 , and compound 3IIl showed 90% larvicidal activities at a concentration of 0.5 mg L-1 . The LC50 value of 3IIl was 0.20 mg L-1 , which indicated that it may be used as a potential leading compound for further structural optimisation. Furthermore, brief comparative molecular field analysis (CoMFA) models were established to study the structure-activity relationships (SARs) of the title compounds. CONCLUSION: Compound 3IIl may be used as a potential leading compound for further structural optimisation, and SARs and CoMFA models could provide reliable clues for further structural optimisation. © 2016 Society of Chemical Industry.

Discovery of diamide compounds as diacylglycerol acyltransferase 1 (DGAT1) inhibitors.

Diamide compounds were identified as potent DGAT1 inhibitors in vitro, but their poor molecular properties resulted in low oral bioavailability, both systemically and to DGAT1 in the enterocytes of the small intestine, resulting in a lack of efficacy in vivo. Replacing an N-alkyl group on the diamide with an N-aryl group was found to be an effective strategy to confer oral bioavailability and oral efficacy in this lipophilic diamide class of inhibitors.

Bicyclic heterocyclic anthranilic diamides as ryanodine receptor modulators with insecticidal activity.

The diamide insecticides act on the ryanodine receptor (RyR). The synthesis of various bicyclic anthranilic derivatives is reported. Their activity against the insect ryanodine receptor (RyR) and their insecticidal activity in the greenhouse is presented, as well as structure activity relationship considerations.

S-Michael additions to chiral dehydroalanines as an entry to glycosylated cysteines and a sulfa-Tn antigen mimic.

Stereoselective sulfa-Michael addition of appropriately protected thiocarbohydrates to chiral dehydroalanines has been developed as a key step in the synthesis of biologically important cysteine derivatives, such as S-(ß-D-glucopyranosyl)-D-cysteine, which has not been synthesized to date, and S-(2-acetamido-2-deoxy-α-D-galactopyranosyl)-L-cysteine, which could be considered as a mimic of Tn antigen. The corresponding diamide derivative was also synthesized and analyzed from a conformational viewpoint, and its bound state with a lectin was studied.

Synthesis and insecticidal evaluation of novel anthranilic diamides containing N-substitued nitrophenylpyrazole.

To cope with developing pest resistance and ecological problems associated with conventional insecticides and to search for potent insecticides targeting at ryanodine receptor (RyR), a series of novel anthranilic diamides containing N-substitued nitrophenylpyrazole were designed and synthesized. The insecticidal activities of target compounds against oriental armyworm (Mythimna separata) and diamondback moth (Plutella xylostella) were evaluated in our greenhouse by bio-assay tests and the relative structure-activity relationships were briefly discussed. Most compounds exhibited moderate to high activities, in which G7 and K5 showed high activity against oriental armyworm and K2 and K4 against diamondback moth even better than the control-chlorantraniliprole. The calcium imaging technique was used to investigate the effects of several typical title compounds on the [Ca(2+)](i), especially the effects of G7 on the intracellular calcium ion concentration ([Ca(2+)](i)) in neurons, which indicated that some title compounds were potent activators of the RyR.

Synthesis, insecticidal activity, and structure-activity relationship (SAR) of anthranilic diamides analogs containing oxadiazole rings.

A series of anthranilic diamides analogs (3­11, 16­24) containing 1,2,4- or 1,3,4-oxadiazole rings were synthesized and characterized by (1)H NMR, MS and elemental analyses. The structure of 3-bromo-N-(2-(3-(4-bromophenyl)-1,2,4-oxadiazol-5-yl)-4-chloro-6-methylphenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (18, CCDC-) was determined by X-ray diffraction crystallography. The insecticidal activities against Plutella xylostella and Spodoptera exigua were evaluated. The results showed that most of title compounds displayed good larvicidal activities against P. xylostella, especially compound 3-bromo-N-(4-chloro-2-methyl-6-(5-(methylthio)-1,3,4-oxadiazol-2-yl)phenyl)-1-(3-chloropyridin-2-yl)-1H-pyrazole-5-carboxamide (6), which displayed 71.43% activity against P. xylostella at 0.4 µg mL(-1) and 33.33% against S. exigua at 1 µg mL(-1). The structure-activity relationship showed that compounds decorated with a 1,3,4-oxadiazole were more potent than compounds decorated with a 1,2,4-oxadiazole, and different substituents attached to the oxadiazole ring also affected the insecticidal activity. This work provides some hints for further structure modification and the enhancement of insecticidal activity.

Synthesis, crystal structure and biological activity of novel anthranilic diamide insecticide containing alkyl ether group.

In searching for environmentally benign insecticides with high activity, low toxicity and low residue, two series of novel anthranilic diamide containing methyl ether and isopropyl ether group were designed and synthesized. All of the compounds were characterized by (1)H NMR spectroscopy, (13)C NMR spectroscopy and elemental analysis. The single crystal structure of 19j was determined by X-ray diffraction. The insecticidal activities of the new compounds were evaluated. The results showed that some compounds exhibited excellent insecticidal activities against Lepidoptera pests. Among this series, compound, 18l showed 100 % larvicidal activity against Mythimna separate Walker, Plutella xylostella Linnaeus and Laphygma exigua Hubner at the test concentration, which was equal to the available chlorantraniliprole.

Short synthesis of diamide-linked sucrose macrocycles.

A convenient route to macrocyclic diamide-linked macrocyclic derivatives with a sucrose scaffold is presented. Reaction of sucrose based amines (o- and m-) with acid dichlorides afforded the monomeric macrocycles in excellent yields, while reaction of the p-amines also provided dimeric products.

Cascade annulation of malonic diamides: a concise synthesis of polycyclic pyrroloindolines.

A concise synthesis of polycyclic pyrroloindolines from simple malonic diamides via an intramolecular oxidative coupling/condensative cyclization cascade process is reported. The reaction provides an efficient method to construct polycyclic pyrroloindolines in good to excellent yields, which should be useful in the synthesis of natural products and pharmaceutical molecules.

Anthranilic acid-based diamides derivatives incorporating aryl-isoxazoline pharmacophore as potential anticancer agents: design, synthesis and biological evaluation.

A series of novel anthranilic diamides derivatives containing aryl-isoxazoline moiety were designed and synthesized as a part of our ongoing search for potential anticancer agents. Their structures were confirmed by (1)H NMR, (13)C NMR and ESI-MS analyses. The preliminary assays showed that some of the compounds displayed moderate to good antitumor activities against human lung cancer (NCI-H460), hepatocellular liver carcinoma (HepG2), gastric cancer (SGC-7901 and BGC-823) and breast epithelial adenocarcinoma (MCF-7) cell lines at µM level, which might be developed as novel lead scaffold for potential anticancer agents.

Synthesis, study on anti-arthritic, anti-inflammatory activity and toxicity of some novel bis-oxy cyclophane diamides.

A series of bis-oxy cyclophane diamides with bis(aminomethyl)m-terphenyl as spacer have been synthesized and characterized from spectral and analytical data. All the cyclophane diamides exhibit better anti-arthritic activity than the reference drug viz. diclofenac sodium. Some of the cyclophane diamides exhibit good anti-inflammatory activity. The cyclophane amide 4 and 5 do not show any evidence of mutagenicity and cytotoxicity.