Biphenylacetic Acid Research Articles

Nanofibrous polypeptide hydrogels with collagen-like structure as biomimetic extracellular matrix

Supramolecular peptides exhibit obvious similarities with collagen fibers in terms of self-assembly characteristics, nanofibrous structure, and responsiveness to external stimuli. Here, a series of supramolecular peptides were developed by altering the amino acid sequence, enabling the self-assembly of three types of 4-biphenylacetic acid (BPAA)-tripeptides into fibrous hydrogel through hydrogen bonding and π–π stacking under the influence of ion induction. Transmission electron and scanning electron microscopies revealed that the diameter of the fiber within nanofibrous hydrogels was ~ 10 and ~ 40 nm, respectively, which was similar with the self-assembled collagen fibers. For this reason, these hydrogels could be considered as a biomimetic extracellular substitute. Meanwhile, the gelation concentration induced by ions was even lower than 0.66 wt%, with an elastic modulus of ~ 0.27 kPa, corresponding to a water content of 99.34 wt%. In addition, the three supramolecular hydrogels were found to be good substrates for L929 cell adhesion and MC-3T3 cell proliferation. The overall results implied that BPAA-based hydrogels have a lucrative application potential as cell carriers.Graphical

Stimuli-responsive biphenyl-tripeptide supramolecular hydrogels as biomimetic extracellular matrix scaffolds for cartilage tissue engineering

Supramolecular hydrogel composed of aromatic short peptide gelator was an attractive biomaterial owing to its simple and convenient synthetic route, nano-fibrillar microstructure resembling natural collagen fibers and intelligent response to external stimulus. Herein, stimuli-responsive biphenyl-tripeptide supramolecular hydrogels was prepared to simulate extracellular matrix scaffolds by temperature switch, ion induction and pH switch. The amino acid arrangement substantially affected gelation behavior, only BPAA-βAFF and BPAA-FFβA could form nanostructured supramolecular hydrogels with 8-10 nm nanotubes or nanofibers by potential intermolecular hydrogen bond interactions and π-π stacking. The minimum gelation concentration (MGC) and maximum storage modulus were 0.4 mM (0.023 wt%) and around 8.2 KPa. The two supramolecular hydrogels could support adhesion and proliferation of L929 cells. Moreover, the BPAA-βAFF hydrogel promoted proliferation and ECM secretion of chondrocytes in vitro, and facilitate the phenotype maintenance of hyaline cartilage. All the results demonstrated that BPAA-βAFF hydrogel hold great potential application prospects in cartilage tissue engineering. Statement of SignificanceDiphenylalanine was served as a core segment conjugating with 4-biphenylacetic acid (BPAA) to produce biphenyl-tripeptide compounds with transforming amino sequence, and multiple external stimuli was applied to study the gelation properties of the aromatic short peptide gelators. “FF” brick (phenylalanine-phenylalanine) was crucial for formation of fibrous supramolecular hydrogels. Meanwhile, the sequence of amino acids arrangement also had an essential effect on the gelation behavior. Optimal BPAA-βAFF with ultra-low minimum gelation concentration (0.4 mM, about 0.023 wt%) and similar microstructure to extracellular matrix (ECM) of nature cartilage tissue could promote the proliferation and ECM secretion of chondrocytes in vitro, and facilitate the formation of hyaline cartilage.

Palladium-catalyzed directed synthesis of ortho-deuterated phenylacetic acid and analogues.

The synthesis of deuterium-labeled organic compounds is of increased interest, especially after the approval of deutetrabenazine by the Food and Drug Administration in 2014. The selective incorporation of deuterium in the place of hydrogen not only represents uniqueness in terms of a novel chemical class, but it also can improve the pharmacokinetic profiles of drug molecules while retaining potency and other parameters; thus, hydrogen-deuterium (H/D) exchange methods have been proven to be powerful additions in different areas of chemical science. In that regard, metal-catalyzed deuterium labeling via C-H activation mediated by a unique inbuilt directing group (DG) can play a significant role in the synthesis of novel deuterated chemical entities. In this context, herein, we divulge our results relating to Pd(ii)-catalyzed deuterium incorporation (>97%) at the γ C(sp2)-position of pyridone-containing phenylacetic acid derivatives, where 3-amino-1-methyl-1H-pyridin-2-one (AMP) not only acts as an efficient N,O-directing group, but it also constitutes a part of the target molecules of medicinal importance. Our methodology, which has been optimized based on the effects of temperature, catalyst, time, and substrate scope, shows advantages over existing protocols, with non-selectivity or meager deuteration or the use of an expensive metal (catalytic or super stoichiometric) and a deuterated solvent, reported previously for the deuteration of phenylacetic acid and its derivatives. Moreover, towards our aim of synthesizing deuterium-labeled biologically relevant compounds, the gram scale synthesis of a deuterated analogue of biphenyl acetic acid (3), known to have activity against epileptic seizures, has also been successfully accomplished in high yields and with excellent isotope enrichment via implementing this protocol.

Synthesis, Characterization, Structural Description, Micellization Behavior, DNA Binding Study and Antioxidant Activity of 4, 5 and 6‐Coordinated Copper(II) and Zinc(II) Complexes

Four mononuclear copper(II) and zinc(II) complexes were synthesized by the reaction of copper and zinc salts with 3,4‐dichlorophenylactic acid, 2‐bromophenylactic acid, biphenylacetic acid (O‐donor ligand) and bipyridine (N‐donor ligands) having the general formulae [(L)2Cu(bp)(H2O)] (1), [(BpA)2Cu(bp)] (2), [(L)2Zn(bp)(H2O)] (3) and [(L*)2Zn(bp)] (4) (L = 3,4‐dichlorophenylacetate, L* = 2‐bromophenylacetate bp = bipyridine, and BpA = biphenylacetate). Structures of all compounds were characterized through FT‐IR spectroscopy and X‐ray diffraction analysis. FT‐IR spectra of all complexes confirmed the binding mode of Cu‐O and Zn‐O. XRD data revealed that complexes 1–3 exhibited distorted octahedral arrangement, whereas complex 4 has a distorted tetrahedral environment. Micellization behavior was examined with anionic surfactant (SDS) by conductance measurement as well as absorption spectral analysis. DNA binding study was assessed through viscosity measurement and UV/Vis spectrophotometry. DPPH free radical scavenging assay was measured by UV/Vis spectrophotometry. The results showed nice biological potential of all the complexes.

Potential application of novel liquid crystal nanoparticles of isostearyl glyceryl ether for transdermal delivery of 4-biphenyl acetic acid.

Novel liquid crystal nanoparticles (LCNs) composed of isostearyl glyceryl ether (GE-IS) and ethoxylated hydrogenated castor oil (HCO-60) were developed for the enhanced transdermal delivery of 4-biphenyl acetic acid (BAA). The physical properties and pharmaceutical properties of the LCNs were measured. The interaction between the intercellular lipid model of the stratum corneum and the LCNs was observed to elucidate the skin permeation mechanism. In the formulation, the LCNs form niosomes with mean particles sizes of 180-300nm. The skin absorption mechanisms of LCNs are different, depending upon the application and buffer concentration. The LCNs composed of GE-IS and HCO-60 are attractive tools for use as transdermal drug delivery systems carriers for medicines and cosmetics, due to their high efficiency and safety.

Studies and Synthesis of Substituted 4-Biphenyl Acetamide Derivatives

A new series of substituted 4-biphenylamides have been synthesized by condensation of 4-biphenyl acetic acid with different primary amines (aromatic and aliphatic). 4-Biphenyl acetic acid was first treated with thionyl chloride in dry benzene to prepare substituted 4-biphenyl acetyl chloride, which is then treated with different aliphatic or aromatic amines to synthesize various substituted 4-biphenyl acid-amide derivatives. The structure of newly synthesized compounds has been established by analytical and spectral methods. These synthesized compounds have shown antifungal properties against Fusarium udum and Curvularia lunata.

Molecular Modeling of 4¢,5-Disubstituted Biphenyl Acetic Acid Molecules for their Anti-inflammatory Activity through 3D-QSAR, Docking and Molecular Dynamics Simulation

Molecular Modeling of 4¢,5-Disubstituted Biphenyl Acetic Acid Molecules for their Anti-inflammatory Activity through 3D-QSAR, Docking and Molecular Dynamics Simulation

Discovery of Potent Non-nucleoside Inhibitors of Dengue Viral RNA-Dependent RNA Polymerase from Fragment Screening and Structure-Guided Design.

Flavivirus NS5 RNA-dependent RNA polymerase (RdRp) is an important drug target. Whilst a number of allosteric inhibitors have been described for Hepatitis C virus RdRp, few have been described for DENV RdRp. In addition, compound screening campaigns have not yielded suitable leads for this enzyme. Using fragment-based screening via X-ray crystallography, we identified a biphenyl acetic acid fragment that binds to a novel pocket of the dengue virus (DENV) RdRp, in the thumb/palm interface, close to its active site (termed "N pocket"). Structure-guided optimization yielded nanomolar inhibitors of the RdRp de novo initiation activity, with low micromolar EC50 in DENV cell-based assays. Compound-resistant DENV replicons exhibited amino acid mutations that mapped to the N pocket. This is the first report of a class of pan-serotype and cell-active DENV RdRp inhibitors and provides a significant opportunity for rational design of novel therapeutics against this proven antiviral target.

Synthesis and biocidal screening of Bromo-Substituted 4-biphenyl acetamides derivatives.

The present paper deals with the synthesis of Bromo-Substituted 4-biphenyl acetic acid amides by condensation of corresponding acid chlorides with suitable amines. the structure of newly synthesized compounds were elucidated on the basis of their IR, TLC and elemental analysis data. The compounds were also screened for their anti-bacterial and anti-fungal activity.

PHYSICOCHEMICAL CHARACTERIZATION AND EVALUATION OF TELMISARTAN: HYDROXYPROPYL-β-CYCLODEXTRIN: TWEEN 80 INCLUSION COMPLEX

Objective: The present work was aimed to study the effect of the ternary component on complexation efficiency of cyclodextrins towards telmisartan which is a poorly soluble anti-hypertensive agent.Methods: The elucidation of inclusion complexation of telmisartan (TEL) with hydroxypropyl-β-cyclodextrin (HP-β-CD) in the presence and absence of tween 80 was done by investigating their interactions in solid and solution state. The solid state characterization was performed using differential scanning calorimetry (DSC), powder X-ray diffraction studies (PXRD) fourier transform infra-red spectroscopy (FTIR) studies. The host guest stoichiometry was confirmed in solution state by proton nuclear magnetic resonance (1HNMR) and solution calorimetry studies. The improvement in solubility was evaluated through dissolution studies, which was further confirmed by in vivo studies.Results: In solution state, the phase solubility studies indicated 1:1 stoichiometry between TEL and HP-β-CD both in presence and absence of tween 80. The NMR and molecular modelling studies indicated the insertion of N-methyl benzimidazole and biphenyl carboxylate regions of TEL into HP-β-CD cavity suggesting the coexistence of two 1:1 complexes in equilibrium with each other. The stability constants, K1 (imidazole region of TEL-CD) and K2 (biphenyl acetic acid region of TEL-CD), were enhanced in the presence of tween 80 as evident by the higher value of stability constants. Efficacy of ternary complex was established by a significant decrease in the systolic blood pressure of deoxycorticosterone acetate (DOCA) induced hypertensive rats.Conclusion: It can be concluded that solubility of TEL was increased by encapsulation with HP-β-CD. Tween 80 further increased the complexation efficiency and decreased the bulk of cyclodextrin.

In silico Screening and Evaluation of the Anticonvulsant Activity of Docosahexaenoic Acid-Like Molecules in Experimental Models of Seizures.

Background:Resistance to antiepileptic drugs and the intolerability in 20-30% of the patients raises demand for developing new drugs with improved efficacy and safety. Acceptable anticonvulsant activity, good tolerability, and inexpensiveness of docosahexaenoic acid (DHA) make it as a good candidate for designing and development of the new anticonvulsant medications.Methods:Ten DHA-based molecules were screened based on in silico screening of DHA-like molecules by root-mean-square deviation of atomic positions, the biological activity score of Professional Association for SQL Server, and structural requirements suggested by pharmacophore design. Anticonvulsant activity was tested against clonic seizures induced by pentylenetetrazole (PTZ, 60 mg/kg, i.p.) and tonic seizures induced by maximal electroshock (MES, 50 mA, 50 Hz, 1 ms duration) by intracerebroventricular (i.c.v.) injection of the screened compounds to mice.Results:Among screened compounds, 4-Phenylbutyric acid, 4-Biphenylacetic acid, phenylacetic acid, and 2-Phenylbutyric acid showed significant protective activity in pentylenetetrazole test with ED50 values of 4, 5, 78, and 70 mM, respectively. In MES test, shikimic acid and 4-tert-Butylcyclo-hexanecarboxylic acid showed significant activity with ED50 values 29 and 637 mM, respectively. Effective compounds had no mortality in mice up to the maximum i.c.v. injectable dose of 1 mM.Conclusion:Common electrochemical features and three-dimensional spatial structures of the effective compounds suggest the involvement of the anticonvulsant mechanisms similar to the parent compound DHA.

Discovery of Potent Non-Nucleoside Inhibitors of Dengue Viral RNA-Dependent RNA Polymerase from a Fragment Hit Using Structure-Based Drug Design.

The discovery and optimization of non-nucleoside dengue viral RNA-dependent-RNA polymerase (RdRp) inhibitors are described. An X-ray-based fragment screen of Novartis' fragment collection resulted in the identification of a biphenyl acetic acid fragment 3, which bound in the palm subdomain of RdRp. Subsequent optimization of the fragment hit 3, relying on structure-based design, resulted in a >1000-fold improvement in potency in vitro and acquired antidengue activity against all four serotypes with low micromolar EC50 in cell-based assays. The lead candidate 27 interacts with a novel binding pocket in the palm subdomain of the RdRp and exerts a promising activity against all clinically relevant dengue serotypes.

Enhancing Skin Permeation of Biphenylacetic Acid (BPA) Using Salt Formation with Organic and Alkali Metal Bases.

In the present study, a series of organic and alkali metal salts of biphenylacetic acid (BPA) have been prepared and evaluated in vitro for percutaneous drug delivery. The physicochemical properties of BPA salts were determined using solubility measurements, DSC, and IR. The DSC thermogram and FTIR spectra confirmed the salt formation with organic and alkali metal bases. Among the series, salts with organic amines (ethanolamine, diethanolamine, triethanolamine, and diethylamine) had lowered melting points while the alkali metal salt (sodium) had a higher melting point than BPA. The in vitro study showed that salt formation improves the physicochemical properties of BPA, leading to improved permeability through the skin. Amongst all the prepared salts, ethanolamine salt (1b) showed 7.2- and 5.4-fold higher skin permeation than the parent drug at pH 7.4 and 5.0, respectively, using rat skin.

Safe Palladium-Catalyzed Cross-Couplings with Microwave Heating Using Continuous-Flow Silicon Carbide Reactors

Herein we present a 200 mm × 3 mm Øi silicon carbide (SiC) tube reactor for use in a commercially available microwave heated continuous-flow system. The SiC flow reactor enables palladium(0)-catalyzed reactions that, due to precipitation and subsequent hot spot formation, often followed by reactor failure, are unsuitable to conduct in standard microwave-transparent borosilicate glass reactors. We report continuous-flow protocols for the Mizoroki–Heck reaction (10 examples, 81–86% yield) as well as the Suzuki–Miyaura cross-coupling (14 examples, 70–87% yield), showing the utility of the SiC reactor. Furthermore, we performed a scale-out of the NSAID biphenylacetic acid, achieving outputs of 14 mmol/h of the Suzuki–Miyaura reaction, and a 72% overall yield over three steps. The SiC reactor enabled fast and efficient temperature control, high robustness, and easy maintenance.

Potential use of a megamolecular polysaccharide sacran as a hydrogel-based sustained release system.

A megamolecular polysaccharide sacran was newly extracted from cyanobacterium Aphanothece sacrum. Sacran has many preferable properties for transdermal application, e.g. a safe biomaterial, a high moisturizing effect, a formation of film and hydrogel. Additionally, it was recently discovered that sacran has an anti-inflammatory effect for atopic dermatitis model mice. In this study, in order to evaluate the feasibility of sacran-hydrogel as a novel sustained release system, we prepared a sacran-hydrogel containing 4-biphenyl acetic acid (BPAA, an acidic drug), prednisolone (PD, a neutral drug) or chlorpheniramine maleate (CPM, a basic drug), and performed the in vitro release studies. The sacran-hydrogel containing BPAA, PD or CPM provided a sustained release profile in accordance with a quasi-Fickian diffusion model. Furthermore, the release rate of drugs from sacran-hydrogels can be controlled by adjusting the concentration of aluminum chloride as a cross linker. These results suggest the potential use of sacran-hydrogel as a sustained release system for drugs.

Carrier-linked mutual prodrugs of biphenylacetic acid as a promising alternative to bioprecursor fenbufen: design, kinetics, and pharmacological studies

Novel mutual prodrugs of biphenylacetic acid were designed as a promising gastro-protective alternative to fenbufen. Biphenyacetic acid was covalently linked with two non-essential amino acids (D-phenylalanine and glycine) possessing wound healing, analgesic, and anti-inflammatory properties. The prodrugs exhibited good stability in stomach homogenates while hydrolytic release of biphenylacetic acid was observed in phosphate buffer, small intestinal homogenates, and 80% human plasma. In vivo behavior of prodrugs on oral administration to Wistar rats demonstrated 33-45% release of biphenylacetic acid in blood over a period of 24 h indicating passage of intact prodrugs to colon, colonic release of parent drug followed by its absorption through colonic mucosa into systemic circulation. Prodrugs were extensively evaluated for analgesic, anti-inflammatory, anti-arthritic, and ulcerogenic activities. Biochemical, haemetological, histopathological, and radiological studies were also performed. Conversion of bioprecusor fenbufen into mutual carrier-linked prodrugs proved to be promising alternative in terms of reduced ulcerogenic propensity, longer duration of analgesia, enhanced/prolonged anti-inflammatory activity, and superior anti-arthritic effect. These prodrugs could be developed further for chronotherapy of rheumatoid arthritis.

Optimisation of biphenyl acetic acid inhibitors of diacylglycerol acetyl transferase 1 – the discovery of AZD2353

Focus on ligand efficiency, ligand lipophilicity efficiency, and conformational restriction led to the discovery of AZD2353.

Reducing ulcerogenic potential of biphenyl acetic acid: Design and development of chimeric derivatives with amino acids

In an attempt to minimize the ulcerogenic potential and associated gastro-intestinal toxicity of bioprecursor fenbufen and its active metabolite biphenyl acetic acid, carrier-linked chimeric derivatives of the latter were designed and synthesized using amino acids as the promoities. DCC coupling method was used for the synthesis of these amides. The chimeras were characterized by IR and 1H NMR. Pharmacological investigations were carried out in animal models for analgesic, anti-inflammatory, anti-arthritic and ulcerogenic activities. The chimeras exhibited high gastro-sparing effect; quick onset and longer duration of analgesia; enhanced/prolonged anti-inflammatory activity and better anti-arthritic effect than fenbufen or biphenyl acetic acid. These derivatives could be useful as a chronotherapy for rheumatoid arthritis due to their prolonged analgesic and anti-inflammatory effects.

Intercalation and Controlled Release of Bioactive Ions Using a Hydroxy Double Salt

Two bioactive drug molecules (mefenamic acid and 4-biphenylacetic acid) were successfully intercalated into the hydroxy double salt (HDS) [Zn5(OH)8](NO3)2·yH2O. The resulting nanocomposites were fu...

ChemInform Abstract: Sodium [2′‐[(Cyclopropanecarbonyl‐ethyl‐amino)‐methyl] ‐4′‐(6‐ethoxy‐pyridin‐3‐yl)‐6‐methoxy‐biphenyl‐3‐yl]‐acetate (AM432): A Potent, Selective Prostaglandin D2 Receptor Antagonist.

AbstractStructure—activity‐relationship studies of recently discovered biphenyl acetic acid based DP2 antagonists culminate in the identification of the title compound (I) as a potential candidate for clinical development.