scholarly journals Design, synthesis and application of carbazole macrocycles in anion sensors

2020 ◽  
Vol 16 ◽  
pp. 1901-1914 ◽  
Author(s):  
Alo Rüütel ◽  
Ville Yrjänä ◽  
Sandip A Kadam ◽  
Indrek Saar ◽  
Mihkel Ilisson ◽  
...  
Keyword(s):  
Binding Constants ◽  
Ion Selective Electrodes ◽  
Proof Of Concept ◽  
Design Synthesis ◽  
H Nmr ◽  
Binding Behavior ◽  
Prototype Development ◽  
Solvent Systems ◽  
Fine Tune ◽  
Acyl Halides

Carboxylate sensing solid-contact ion-selective electrodes (ISEs) were created to provide a proof-of-concept ISE development process covering all aspects from in silico ionophore design to functional sensor characterization. The biscarbazolylurea moiety was used to synthesize methylene-bridged macrocycles of different ring size aiming to fine tune selectivity towards different carboxylates. Cyclization was achieved with two separate strategies, using either amide synthesis to access up to –[CH2]10– macrocycles or acyl halides to access up to –[CH2]14– macrocycles. Seventy-five receptor–anion complexes were modelled and studied with COSMO-RS, in addition to all free host molecules. In order to predict initial selectivity towards carboxylates, 1H NMR relative titrations were used to quantify binding in DMSO-d 6/H2O solvent systems of two proportions – 99.5%:0.5% m/m and 90.0%:10.0% m/m, suggesting initial selectivity towards acetate. Three ionophores were selected for successful sensor prototype development and characterization. The constructed ion-selective electrodes showed higher selectivity towards benzoate than acetate, i.e., the selectivity patterns of the final sensors deviated from that predicted by the classic titration experiments. While the binding constants obtained by NMR titration in DMSO-d 6/H2O solvent systems provided important guidance for sensor development, the results obtained in this work emphasize the importance of evaluating the binding behavior of receptors in real sensor membranes.

Synthesis and Numerical Analysis of Compliant devices – A Topology Optimization Approach for Mechanisms and Robotic Systems

2021 ◽  
Author(s):  
Premanand Sathyanarayanamurthi ◽  
ARUNKUMAR GOPAL
Keyword(s):  
Topology Optimization ◽  
Optimization Design ◽  
Rectangular Domain ◽  
Dynamic State ◽  
Optimization Approach ◽  
Design And Development ◽  
Design Synthesis ◽  
Final Destination ◽  
Prototype Development ◽  
External Forces

Abstract The Topology Optimization design invariably shall be used in various applications like Aerojet designs, Aircraft Engineering designs and innovative systems for improving the efficiency of structure. The paper emphasizes more on general Topology Optimization design for a rectangular domain. The domain numerically analyzed with defined geometry setting and defined boundary conditions for finding the Stress and displacement. In this Topology Optimization Design synthesis, the result is suitable volume and mass reduction in the Aerojet application parts which further can be taken for Prototype development in 3D printing and experimentally test with safety characteristics and compares Objective functions chosen for design and development. The design can be used for other various automotive and aerospace devices based on deformation level and application of external forces. The Final destination of this design and development ends with passing Fatigue Endurance test cycle test pass condition in Aerojet and automotive vehicles in static and dynamic state.

scholarly journals NanoMIP-Based Solid Phase Extraction of Fluoroquinolones from Human Urine: A Proof-of-Concept Study

Separations ◽  
2021 ◽  
Vol 8 (11) ◽  
pp. 226
Author(s):  
Matteo Chiarello ◽  
Laura Anfossi ◽  
Simone Cavalera ◽  
Fabio Di Di Nardo ◽  
Thea Serra ◽  
...  
Keyword(s):  
Solid Phase Extraction ◽  
Human Urine ◽  
Solid Phase ◽  
Extraction Methods ◽  
Hplc Method ◽  
Limited Attention ◽  
Preliminary Treatment ◽  
Phase Extraction ◽  
Proof Of Concept ◽  
Binding Behavior

NanoMIPs that are prepared by solid phase synthesis have proven to be very versatile, but to date only limited attention has been paid to their use in solid phase extraction. Thus, since nanoMIPs show close similarities, in terms of binding behavior, to antibodies, it seems relevant to verify if it is possible to use them as mimics of the natural antibodies that are used in immunoextraction methods. As a proof-of-concept, we considered prepared nanoMIPs against fluoroquinolone ciprofloxacin. Several nanoMIPs were prepared in water with polymerization mixtures of different compositions. The polymer with the highest affinity towards ciprofloxacin was then grafted onto a solid support and used to set up a solid phase extraction–HPLC method with fluorescence detection, for the determination of fluoroquinolones in human urine. The method resulted in successful selection for the fluoroquinolone antibiotics, such that the nanoMIPs were suitable for direct extraction of the antibiotics from the urine samples at the µg mL−1 level. They required no preliminary treatment, except for a 1 + 9 (v/v) dilution with a buffer of pH 4.5 and they had good analyte recovery rates; up to 85% with precision in the range of 3 to 4.5%, without interference from the matrix. These experimental results demonstrate, for the first time, the feasibility of the use of nanoMIPs to develop solid phase extraction methods.

scholarly journals Synthesis, Characterization, and BSA Binding Studies of Some New Benzamides Related to Schiff Base

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
M. K. Prashanth ◽  
M. Madaiah ◽  
H. D. Revanasiddappa ◽  
K. N. Amruthesh
Keyword(s):  
Schiff Base ◽  
Antioxidant Activities ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Binding Constants ◽  
Spectral Studies ◽  
Spectroscopic Techniques ◽  
Binding Studies ◽  
Mass Spectral ◽  
H Nmr

Condensation of amine 1 with aldehyde 2 gives Schiff base, N-(4-((benzofuran-2-ylmethylene) amino)phenyl)acetamide 3. Schiff base on N-acylation with different substituted acid chlorides in the presence of triethylamine gives the corresponding benzamides, N-acetyl-N-(4-((benzofuran-2-ylmethylene)amino)phenyl)substitutedbenzamide (NABP) 5a–j. The structures of newly synthesized compounds were characterized by elemental analysis, 1H NMR, 13C NMR FT-IR, and mass spectral studies. Compounds 3 and 5a–j have been screened for their antimicrobial activity using the disc diffusion and minimum inhibitory concentration (MIC) method against the selected bacterial and fungal strain. Compounds 5a, 5e, 5g, and 5h were found to be more active against all tested strains. The antioxidant properties were evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging methods. Compounds 5i and 5j showed predominant antioxidant activities among the synthesized analogues. The interaction between NABP and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopic techniques at 298 K under imitated physiological conditions. The results revealed that NABP caused the fluorescence quenching of BSA through a static quenching procedure. The binding constants and the number of binding sites were calculated. The binding distance between the donor (BSA) and acceptor (NABP) was determined based on Forster’s theory.

Host-guest interactions of cyclodextrins and metalloporphyrins: supramolecular building blocks toward artificial heme proteins

2004 ◽  
Vol 08 (02) ◽  
pp. 125-140 ◽  
Author(s):  
Huchen Zhou ◽  
John T. Groves
Keyword(s):  
Binding Constant ◽  
Molecular Design ◽  
Covalent Binding ◽  
Binding Constants ◽  
Building Blocks ◽  
Binding Pocket ◽  
Axial Ligand ◽  
Pyridyl Nitrogen ◽  
H Nmr ◽  
Self Assembled

Cyclodextrins are versatile building blocks for a variety of macromolecules due to the inclusion complexes that are formed with hydrophobic organic molecules. Cyclodextrin-porphyrin interactions are of particular interest since cyclodextrins can serve as a non-covalent binding pocket while metalloporphyrins could serve as the heme analogs in the construction of heme protein model compounds. Various approaches to the design and assembly of biomimetic porphyrin constructs are compared and contrasted in this minireview with a particular emphasis on self-assembled and porphyrin-cyclodextrin systems. Several recent advances from our laboratories are described in this context. A sensitive fluorescent binding probe, 6A-N-dansyl-permethylated-β-cyclodextrin (Dan-NH-TMCD), was found to form 2:1 complexes with the meso-tetraphenylporphyrins Mn(III)TCPP , Mn(III)TPPS and Mn(III)TF 4 TMAP with high binding constants. A perPEGylated cyclodextrin, heptakis(2,3,6-tri-O-2-(2-(2-methoxyethoxy)ethoxy)ethyl)-β-cyclodextrin (TPCD), has been shown by 1 H NMR spectroscopy to form a 1:1 complex with H 2 TCPP with a binding constant above 108M-1. Such a strong binding constant is the largest found for a 1:1 complex between a monomeric cyclodextrin and a guest. TPCD was also found to bind Mn(III)TCPP with a binding constant of 1.2 × 106 M -1. A novel, self-assembled hemoprotein model, hemodextrin is also described. The molecular design is based on a PEGylated cyclodextrin scaffold that bears both a heme-binding pocket and an axial ligand that binds an iron porphyrin. The binding constant for Fe (III) TPPS (iron(III) meso-tetra(4-sulfonatophenyl)porphyrin) by py-PPCD was determined to be 2 × 106 M -1. The pyridyl nitrogen of py-PPCD was shown to ligate to the iron center by observing signal changes in the Fe(II) -porphyrin 1 H NMR spectrum. This hemodextrin ensemble, a minimalist myoglobin, was shown to bind dioxygen reversibly and to form a stable ferryl species.

scholarly journals Design, Synthesis, and Molecular Docking of 1-(1-(4-Chlorophenyl)-2-(phenylsulfonyl)ethylidene)-2-phenylhydrazine as Potent Nonazole Anticandidal Agent

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Hazem A. Ghabbour ◽  
Maha M. Qabeel ◽  
Wagdy M. Eldehna ◽  
Abdullah Al-Dhfyan ◽  
Hatem A. Abdel-Aziz
Keyword(s):  
Human Breast ◽  
Binding Interaction ◽  
Design Synthesis ◽  
Standard Drug ◽  
H Nmr ◽  
Normal Human Breast ◽  
Normal Human ◽  
Human Breast Cell Line ◽  
Human Breast Cell ◽  
C Nmr

1-(1-(4-Chlorophenyl)-2-(phenylsulfonyl)ethylidene)-2-phenylhydrazine (13) was designed and synthesized as potential nonazole anticandidal agent and precisely characterized by IR,1H NMR,13C NMR, and ESI-MS. The anti-Candidaactivity of13was evaluated against fourCandidaspecies (C. albicans, C. krusei, C. parapsilosis, andC. glabrata). Compound13displayed good anticandidal activities (MIC=0.39, 0.195, 0.39, and 1.56 μmol/mL, resp.) in comparison with that of the standard drug fluconazole (MIC=0.195, inactive, 1.56, and 1.56 μmol/mL, resp.) againstC. albicans, C. krusei, C. parapsilosis, andC. glabrata, respectively. A molecular modeling of the newly synthesized compound13was built in order to investigate its mode of action towards the prospective target cytochrome P450-dependent enzyme lanosterol 14α-demethylase (PDB-code: 1EA1). The docking results showed a similar binding interaction of13and fluconazole at the active site of CYT P450 14α-sterol demethylase. Furthermore, compound13showed no cytotoxicity against normal human breast cell line MCF10A.

Design, Synthesis and Anticancer Activity of 4-Morpholinothieno[3,2-D]-Pyrimidine Derivatives Bearing Chromone Moiety

2014 ◽  
Vol 989-994 ◽  
pp. 568-571 ◽  
Author(s):  
Cheng Yu Sun ◽  
Chen Chen ◽  
Chun Jiang Wu ◽  
Peng Wu Zheng ◽  
Wu Fu Zhu
Keyword(s):  
Anticancer Activity ◽  
Cell Lines ◽  
Cancer Cell ◽  
High Selectivity ◽  
Cancer Cell Lines ◽  
Inhibition Rate ◽  
Pyrimidine Derivatives ◽  
Design Synthesis ◽  
H Nmr

A series of 4-morpholinothieno [3,2-d] pyrimidine derivatives containing chromone moiety (5a-5e) were synthesized and their structures were confirmed by 1H NMR and MS spectrum. The synthesized compounds were evaluated for their cytotoxicity against three cancer cell lines (PC-3, H460, SGC-7901). Two of them exhibited moderate cytotoxicity and high-selectivity against one or more cell lines. At 10μM levels, the inhibition rate of compound 5c against SGC-7901 cell lines was 58.9%, and that of compound 5d against PC-3 cell lines was 56.4%.

scholarly journals Structural characterization and DNA-binding properties of Sm(III) complex with ofloxacin using spectroscopic methods

2009 ◽  
Vol 23 (2) ◽  
pp. 103-111 ◽  
Author(s):  
Changyun Chen ◽  
Kai Chen ◽  
Qi Long ◽  
Meihua Ma ◽  
Fei Ding
Keyword(s):  
Binding Sites ◽  
Nmr Spectra ◽  
Uv Spectroscopy ◽  
Binding Constants ◽  
Binding Properties ◽  
H Nmr ◽  
Elemental Analyses ◽  
Displacement Experiments ◽  
Ct Dna ◽  
Dna Binding Properties

A novel complex Sm(III) complex with ofloxacin was synthesized and characterized on the basis of elemental analyses, molar conductivities, IR spectra, thermal analysis (TG-DSC),1H-NMR spectra. Then, spectrometric titration, ethdium bromide displacement experiments by UV spectroscopy, ionic influence, viscosity measurements and Circular Dichroism (CD) spectroscopic measurements were conducted to characterize the interaction between the complex and CT-DNA. Results obtained indicate that the complex bound with CT-DNA via an intercalation mechanism. The binding constants and binding sites number of the Sm(III) complex with CT-DNA were 1.80×105l·mol−1and 1, respectively.

scholarly journals Synthesis and binding studies of two new macrocyclic receptors for the stereoselective recognition of dipeptides

2010 ◽  
Vol 6 ◽  
Author(s):  
Ana Maria Castilla ◽  
M Morgan Conn ◽  
Pablo Ballester
Keyword(s):  
Hydrogen Bonding ◽  
Peptide Ligands ◽  
Binding Studies ◽  
Design Synthesis ◽  
Macrocyclic Receptors ◽  
H Nmr ◽  
Hydrogen Bonding Pattern ◽  
Conformational Equilibria ◽  
Β Sheets ◽  
Β Sheet

We present here the design, synthesis, and analysis of a series of receptors for peptide ligands inspired by the hydrogen-bonding pattern of protein β-sheets. The receptors themselves can be regarded as strands 1 and 3 of a three-stranded β-sheet, with cross-linking between the chains through the 4-position of adjacent phenylalanine residues. We also report on the conformational equilibria of these receptors in solution as well as on their tendency to dimerize. 1H NMR titration experiments are used to quantify the dimerization constants, as well as the association constant values of the 1:1 complexes formed between the receptors and a series of diamides and dipeptides. The receptors show moderate levels of selectivity in the molecular recognition of the hydrogen-bonding pattern present in the diamide series, selecting the α-amino acid-related hydrogen-bonding functionality. Only one of the two cyclic receptors shows modest signs of enantioselectivity and moderate diastereoselectivity in the recognition of the enantiomers and diastereoisomers of the Ala-Ala dipeptide (ΔΔG 0 1 (DD-DL) = −1.08 kcal/mol and ΔΔG 0 1 (DD-LD) = −0.89 kcal/mol). Surprisingly, the linear synthetic precursors show higher levels of stereoselectivity than their cyclic counterparts.

scholarly journals Microwave Assisted Synthesis of Novel Imidazolopyridinyl Indoles as Potent Antioxidant and Antimicrobial Agents

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Jaiprakash S. Biradar ◽  
Parveen Rajesab ◽  
Sasidhar B. Somappa
Keyword(s):  
Antimicrobial Agents ◽  
Analytical Data ◽  
Antimicrobial Activities ◽  
Microwave Assisted Synthesis ◽  
The Novel ◽  
Design Synthesis ◽  
Mass Spectral ◽  
H Nmr ◽  
Total Antioxidant ◽  
Indole Analogues

We describe herein the design, synthesis, and pharmacological evaluation of novel series of imidazolopyridinyl indole analogues as potent antioxidants and antimicrobials. These novel compounds (3a–i) were synthesized by reacting 3,5-disubstituted-indole-2-carboxylic acid (1a–i) with 2,3-diamino pyridine (2) in excellent yield. The novel products were confirmed by their IR,1H NMR,13C NMR, mass spectral, and analytical data. These compounds were screened for their antioxidant and antimicrobial activities. Among the compounds tested,3a–dshowed the highest total antioxidant capacity, scavenging, and antimicrobial activities. Compounds3c-dand3g-hhave shown excellent ferric reducing activity.

scholarly journals Synthesis, photophysical properties and photodynamic antimicrobial activity of meso 5,10,15,20-tetra(pyren-1-yl)porphyrin and its indium(III) complex

2021 ◽  
pp. A-F
Author(s):  
Jackline Khisa ◽  
Solomon Derese ◽  
John Mack ◽  
Edith Amuhaya ◽  
Tebello Nyokong
Keyword(s):  
Mass Spectrometry ◽  
Antimicrobial Activity ◽  
Fluorescence Quantum Yield ◽  
Photophysical Properties ◽  
Bathochromic Shift ◽  
Intersystem Crossing ◽  
Free Base ◽  
H Nmr ◽  
Solvent Systems ◽  
Dose Dependent

In this study, free-base meso 5,10,15,20-tetra(pyren-1-yl)porphyrin (H2TPyP) and its corresponding indium(III) complex (InClTPyP) were synthesized and characterized on the basis of mass spectrometry, 1H NMR spectroscopy and elemental analysis. InClTPyP was obtained in good yield by treating the free base H2TPyP with indium(III) chloride. Purification of these compounds was achieved through column chromatography using different solvent systems. Metallation of the free base to form a metallo-porphyrin afforded improved photophysical properties. There was a bathochromic shift in wavelength of absorption from the parent free base H2TPyP ([Formula: see text] = 431 nm) to metallated indium(III) complex ([Formula: see text] = 443 nm). The fluorescence quantum yield in H2TPyP was higher ([Formula: see text] = 0.131) than in InClTPyP ([Formula: see text] = 0.017) due to efficient intersystem crossing to the triplet manifold in the metallated porphyrin. Upon illumination, both H2TPyP and InClTPyP show effective dose dependent antimicrobial activity against Staphylococcus aureus with photoinactivation IC[Formula: see text] values of 27.89 and 16.67 [Formula: see text]M, respectively.

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