A synthetic strategy for switching the single ion anisotropy in tetrahedral Co(ii) complexes

2015 ◽  
Vol 51 (18) ◽  
pp. 3739-3742 ◽  
Author(s):  
Shefali Vaidya ◽  
Apoorva Upadhyay ◽  
Saurabh Kumar Singh ◽  
Tulika Gupta ◽  
Subrata Tewary ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Synthetic Strategy ◽  
Tetrahedral Complexes ◽  
First Time

We have shown for the first time, by simply exploiting the hard/soft nature of ligands, single ion magnetic anisotropy of Co(ii) tetrahedral complexes can be switched (+ve to −ve orvice versa) rationally.

Towards the Total Synthesis of Schisandrene: Stereoselective Synthesis of the Dibenzocyclooctadiene Lignan Core

Synlett ◽  
2018 ◽  
Vol 29 (07) ◽  
pp. 908-911 ◽  
Author(s):  
K. Babu ◽  
Arramshetti Venkanna ◽  
Borra Poornima ◽  
Bandi Siva ◽  
B. Babu
Keyword(s):  
Total Synthesis ◽  
Stereoselective Synthesis ◽  
Asymmetric Reduction ◽  
Cross Coupling ◽  
Membered Ring ◽  
Stille Reaction ◽  
Reaction Sequence ◽  
Ring Closing Metathesis ◽  
Synthetic Strategy ◽  
First Time

A stereoselective synthesis of the dibenzocyclooctadiene ­lignan core of the natural product schisandrene is described. Starting from readily available gallic acid, the synthetic strategy involves Suzuki–Miyaura cross-coupling, Stille reaction, and ring-closing metathesis (RCM) in the reaction sequence. The required asymmetric center at C-7′ was established by an asymmetric reduction of a keto compound using the Corey–Bakshi–Shibata (CBS) catalyst. In our approach, the eight-membered ring was achieved by RCM for the first time.

Iridium(III) Complexes Containing 1,10-Phenanthroline and Derivatives: Synthetic, Stereochemical, and Structural Studies, and their Antimicrobial Activity

2013 ◽  
Vol 66 (9) ◽  
pp. 1065 ◽  
Author(s):  
Mallesh Pandrala ◽  
Fangfei Li ◽  
Lynne Wallace ◽  
Peter J. Steel ◽  
Barry Moore II ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Cell Uptake ◽  
Cd Spectra ◽  
Bacterial Strains ◽  
X Ray Diffraction ◽  
E Coli ◽  
Synthetic Strategy ◽  
Bacterial Cell Membrane ◽  
Uptake Studies ◽  
First Time

A convenient synthetic strategy is reported for the series of complexes [Ir(pp)3]3+ (where pp = phen, Me2phen and Me4phen) through the intermediacy of the appropriate [Ir(pp)2(CF3SO3)2]+ species. In the case of [Ir(phen)3]3+, the cation was resolved into its enantiomeric forms, for which the absolute configurations were determined by X-ray diffraction. The availability for the first time of the CD spectra allowed comparison with computed CD spectra. Measurement of the antimicrobial activity of the [Ir(pp)3]3+ species {and the [Ir(pp)2X2]+ (X = Cl–, CF3SO3–) precursors involved in their synthesis}, as well as cell uptake studies with the four bacterial strains S. aureus, methicillin-resistant S. aureus (MRSA), E. coli, and P. aeruginosa, indicated that they showed little activity compared with their Ru(ii) analogues. The results suggest that it is unfavourable for an individual metal centre with a 3+ charge to pass across the bacterial cell membrane.

A Facile Strategy for Synthesis of Porous Cu2O Nanosphere and Application as Nanozymes in Colorimetric Biosensing

2021 ◽  
Author(s):  
Ying Zhu ◽  
Zhilu Zhang ◽  
xinyu song ◽  
Yuxiang Bu
Keyword(s):  
Sodium Hypochlorite ◽  
Synthetic Strategy ◽  
First Time ◽  
Colorimetric Biosensing ◽  
Porous Nanomaterials

Due to the unique advantage, developing a rapid, simple and economical synthetic strategy for porous nanomaterials is of great interest. In this work, for the first time, using sodium hypochlorite...

A Different Approach to the EGFR Inhibitor Gefitinib Involving Solid-Phase Synthesis

Synlett ◽  
2018 ◽  
Vol 29 (10) ◽  
pp. 1346-1350 ◽  
Author(s):  
Luísa Carvalho ◽  
André Sequeira ◽  
Ana Lourenço ◽  
Luísa Ferreira ◽  
Paula Branco ◽  
...  
Keyword(s):  
Solid Phase Synthesis ◽  
Solid Phase ◽  
Solid Support ◽  
Egfr Inhibitor ◽  
Phase Synthesis ◽  
Synthetic Strategy ◽  
Colorimetric Assays ◽  
First Time ◽  
Synthesis Approach

An efficient solid-phase synthesis approach is here reported for the first time to prepare the EGFR inhibitor Gefitinib. The five-step synthetic strategy used FMP resin as the solid support, and FTIR and colorimetric assays were used to track the reaction’s progress. Gefitinib was obtained with an overall yield of 40%.

First Observation of Non-Resonant X-Ray Magnetic Diffraction for Multilayers

2016 ◽  
Vol 698 ◽  
pp. 3-7
Author(s):  
Hidefumi Shimoyama ◽  
Tokiko Osawa ◽  
Hiromi Watanabe ◽  
Kosuke Suzuki ◽  
Hiroshi Sakurai ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Magnetic Hysteresis ◽  
Perpendicular Magnetic Anisotropy ◽  
Diffraction Method ◽  
Magnetic Multilayers ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
Magnetization Direction ◽  
X Ray ◽  
First Time

Co/Pd magnetic multilayers have been prepared by using a sputtering method. Lattice distances and magnetic hysteresis curves have been measured by X-ray diffraction (XRD) measurements and magnetization measurements using a vibrating sample magnetometer (VSM). The XRD measurements have shown that the samples with thinner Pd layers have shorter lattice distances, and the VSM measurements have shown that the samples of thinner Co and thicker Pd layers are closer to those of perpendicular magnetic anisotropy. We have applied the X-ray magnetic diffraction method to the Co/Pd multilayer for the first time and have succeeded in observing a change in the X-ray diffraction intensities by the reversal of the magnetization direction.

Total synthesis of cannabisin F

2014 ◽  
Vol 68 (3) ◽  
Author(s):  
Ya-Mu Xia ◽  
Jun Xia ◽  
Chen Chai
Keyword(s):  
Total Synthesis ◽  
Wittig Reaction ◽  
Aldol Reaction ◽  
Synthetic Strategy ◽  
First Time

AbstractA practical eight-step synthesis of lignanamide cannabisin F starting from vanillin is reported for the first time. This synthetic strategy applies the aldol reaction followed by the Wittig reaction to afford the key 8-O-4′-neolignan intermediate diacid. The diacid was condensed with N,O-protected tyramine giving, after deprotection, cannabisin F.

scholarly journals Insight into D6h Symmetry: Targeting Strong Axiality in Stable Dysprosium(III) Hexagonal Bipyramidal Single-Ion Magnets

2019 ◽  
Author(s):  
Angelos Canaj ◽  
Sourav Dey ◽  
Emma Regincós Martí ◽  
Claire Wilson ◽  
Gopalan Rajaraman ◽  
...  
Keyword(s):  
Single Molecule ◽  
Magnetization Reversal ◽  
Ligand Field ◽  
Single Molecule Magnets ◽  
Uniaxial Magnetic Anisotropy ◽  
Synthetic Strategy ◽  
High Anisotropy ◽  
First Time ◽  
Opening Up ◽  
Insight Into

Three dysprosium(III) single-molecule magnets (SMMs) with the rare hexagonal bipyramidal geometry have been isolated for the first time. Following a novel synthetic strategy where the strong uniaxial ligand field generated by the Ph<sub>3</sub>SiO<sup>-</sup> (Ph<sub>3</sub>SiO<sup>-</sup> = anion of triphenylsilanol) and the 2,4-di-<sup>t</sup>Bu-PhO<sup>-</sup> (2,4-di-<sup>t</sup>Bu-PhO<sup>-</sup> = anion of 2,4-di-tertbutylphenol) ligands combined with the weak equatorial field of the ligand L<sup>N6</sup>, leads to [Dy<sup>III</sup>(L<sup>N6</sup>)(2,4-di-<sup>t</sup>Bu-PhO)<sub>2</sub>](PF<sub>6</sub>) (<b>1</b>), [Dy<sup>III</sup>(L<sup>N6</sup>)(Ph<sub>3</sub>SiO)<sub>2</sub>](PF<sub>6</sub>) (<b>2</b>) and [Dy<sup>III</sup>(L<sup>N6</sup>)(Ph<sub>3</sub>SiO)<sub>2</sub>](BPh<sub>4</sub>) (<b>3</b>) hexagonal bipyramidal complexes with high anisotropy barriers of U<sub>eff</sub> = 973 K for <b>1</b>, U<sub>eff</sub> = 1080 K for <b>2</b> and U<sub>eff</sub> = 1124 K for <b>3 </b>under zero applied dc field. <i>Ab initio</i> calculations predict that the dominant magnetization reversal barrier of these complexes expands up to the 3rd Kramers doublet, thus revealing for the first time the exceptional uniaxial magnetic anisotropy that even the six equatorial donor atoms fail to negate, opening up the possibility to other higher-order symmetry SMMs. <br>

scholarly journals Influence of aluminum substitution on the fi eld of effective magnetic anisotropy and the degree of magnetic texture of anisotropic polycrystalline hexagonal ferrites of barium and strontium for substrates of microstrip devices of microwave electronics

2019 ◽  
Vol 21 (3) ◽  
pp. 166-174
Author(s):  
S. V. Shcherbakov ◽  
A. G. Nalogin ◽  
V. G. Kostishin ◽  
A. A. Alekseev ◽  
E. A. Belokon ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Anisotropy Field ◽  
Ceramic Technology ◽  
Preparation Technology ◽  
Magnetic Texture ◽  
Strontium Hexaferrites ◽  
Barium Hexaferrites ◽  
Microwave Electronics ◽  
Effective Magnetic Anisotropy ◽  
First Time

Abstract. In this paper, the effect of Al3+ ions substitutions on the value of the effective magnetic anisotropy field НАeff and the degree of magnetic texture f of the anisotropic polycrystalline hexagonal barium and strontium ferrites were studied. The samples were obtained by the ceramic technology method and the texture was formed by pressing in a magnetic field. The sample preparation technology presented in detail. The batches of barium hexaferrites were synthesized with the concentration of Al3+ ions: 0.9; 1.4; 2.5 and 2.6 formula units while strontium hexaferrites had Al3+ concentration of 0.1 formula units. It has been shown that by this technology barium and strontium hexaferrites with high value of (in range of 19—35 kOe) and with f = 80—83% could be obtained. The achieved values of НАeff and f could be sufficient for the production of substrates for microstrip microwave devices in millimeter−wave region.For the first time a raise in the degree of magnetic texture of polycrystalline barium hexaferrites with an increase of concentration of Al3+ ions were detected; a slight (5.5—5.8%) magnetic texture of isotropic strontium hexaferrites was also detected. The achieved results discussed in detail. For studied hexaferrites the mechanism of magnetic texture formation during the process of synthesis is proposed.

scholarly journals A Synthetic Glycan Array Containing Cryptococcus Neoformans Glucuronoxylomannan Capsular Polysaccharide Fragments Allows the Mapping of Protective Epitopes

2020 ◽  
Author(s):  
Lorenzo Guazzelli ◽  
Rebecca Ulc ◽  
Anthony Bowen ◽  
Conor Crawford ◽  
Orla McCabe ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Cryptococcus Neoformans ◽  
Capsular Polysaccharide ◽  
Building Blocks ◽  
Oligosaccharide Structure ◽  
Serotype A ◽  
Synthetic Strategy ◽  
First Time ◽  
Insight Into ◽  
Oligosaccharide Structures

A block synthetic strategy to Cryptococcus neoformans glucuronoxylomannan (GXM) capsular polysaccharide part structures has been developed based on di-, tri-, tetra-, penta- and hexasaccharide thioglycoside building blocks. The approach permitted the synthesis of a library of spacer-containing serotype A and D related GXM oligosaccharide structures, ranging from di- to octadecasaccharides. Ten deprotected GXM compounds (mono- to decasaccharide) were printed onto microarray plates and screened with seventeen mouse monoclonal antibodies (mAbs) to GXM. For the first time a GXM oligosaccharide structure (a serotype A decasaccharide), capable of being recognized by neutralizing forms of these GXMspecific mAbs, has been identified, offering insight into the binding epitopes of a range of protective monoclonal antibodies and furthering our efforts to develop semi-synthetic conjugate vaccine candidates against C. neoformans.<br>

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