Search results for "ligandi"

Dynamics of weak interactions in the ligand layer of meta-mercaptobenzoic acid protected gold nanoclusters Au68(m-MBA)32 and Au144(m-MBA)40

2020

Atomically precise metal nanoclusters, stabilized and functionalized by organic ligands, are emerging nanomaterials with potential applications in plasmonics, nano-electronics, bio-imaging, nanocatalysis, and as therapeutic agents or drug carriers in nanomedicine. The ligand layer has an important role in modifying the physico-chemical properties of the clusters and in defining the interactions between the clusters and the environment. While this role is well recognized from a great deal of experimental studies, there is very little theoretical information on dynamical processes within the layer itself. Here, we have performed extensive molecular dynamics simulations, with forces calculated…

Redox-aktiiviset siltaavat ligandit lantanoidikomplekseissa

2017

Redox-aktiiviset siltaavat ligandit on mahdollista hapettaa tai pelkistää suhteellisen pysyviksi radikaaleiksi inertissä atmosfäärissä. Siltaavina ligandeina ne voivat koordinoitua kahden tai useamman metalli-ionin välille. Paramagneettiset siltaavat radikaaliligandit ja lantanoidit ovat lupaavia rakenneosia yksittäismolekyylimagneettien valmistuksessa, sillä radikaalien diffuusit spinorbitaalit voivat peittää lantanoidien 4f-orbitaaleja, jolloin muodostuu voimakas vaihtokytkentä lantanoidin ja radikaalin välille. Lantanoidikompleksien magneettisuus syntyy lantanoidi-ionin elektronien, spin-ratakytkennän ja kidekenttäympäristön vuorovaikutuksista ja siihen vaikuttaa ligandien ja metallin vä…

Virtual screening : development of a novel structure-based method

2013

Discovery of Retinoic Acid-Related Orphan Receptor γt Inverse Agonists via Docking and Negative Image-Based Screening

2018

Retinoic acid-related orphan receptor γt (RORγt) has a vital role in the differentiation of T-helper 17 (TH17) cells. Potent and specific RORγt inverse agonists are sought for treating TH17-related diseases such as psoriasis, rheumatoid arthritis, and type 1 diabetes. Here, the aim was to discover novel RORγt ligands using both standard molecular docking and negative image-based screening. Interestingly, both of these in silico techniques put forward mostly the same compounds for experimental testing. In total, 11 of the 34 molecules purchased for testing were verified as RORγt inverse agonists, thus making the effective hit rate 32%. The pIC50 values for the compounds varied from 4.9 (11 μ…

The Instability of Ni{N(SiMe3)2}2: A Fifty Year Old Transition Metal Silylamide Mystery

2015

The characterization of the unstable NiII bis(silylamide) Ni{N(SiMe3)2}2 (1), its THF complex Ni{N(SiMe3)2}2(THF) (2), and the stable bis(pyridine) derivative trans-Ni{N(SiMe3)2}2(py)2 (3), is described. Both 1 and 2 decompose at ca. 25 °C to a tetrameric NiI species, [Ni{N(SiMe3)2}]4 (4), also obtainable from LiN(SiMe3)2 and NiCl2(DME). Experimental and computational data indicate that the instability of 1 is likely due to ease of reduction of NiII to NiI and the stabilization of 4 through dispersion forces. peerReviewed

Modeling the atomic and electronic structure of nanoparticle-ligand interfaces

2013

Suitability of MMGBSA for the selection of correct ligand binding modes from docking results

2019

The estimation of the correct binding mode and affinity of a ligand into a target protein using computational methods is challenging. However, docking can introduce poses from which the correct binding mode could be identified using other methods. Here, we analyzed the reliability of binding energy estimation using the molecular mechanics‐generalized Born surface area (MMGBSA) method without and with energy minimization to identify the likely ligand binding modes within docking results. MMGBSA workflow (a) outperformed docking in recognizing the correct binding modes of androgen receptor ligands and (b) improved the correlation coefficient of computational and experimental results of rescor…

Computational studies of biomolecular screening and interactions

2015

Controlling Oxidative Addition and Reductive Elimination at Tin(I) via Hemi-Lability.

2021

We report on the synthesis of a distannyne supported by a pincer ligand bearing pendant amine donors that is capable of reversibly activating E–H bonds at one or both of the tin centres through dissociation of the hemi-labile N–Sn donor/acceptor interactions. This chemistry can be exploited to sequentially (and reversibly) assemble mixed-valence chains of tin atoms of the type ArSn{Sn(Ar)H} n SnAr ( n = 1, 2). The experimentally observed (decreasing) propensity towards chain growth with increasing chain length can be rationalized both thermodynamically and kinetically by the electron-withdrawing properties of the –Sn(Ar)H– backbone units generated via oxidative addition. peerReviewed

Oxygen Transfer from Trimethylamine N-oxide to CuI Complexes Supported by Pentanitrogen Ligands

2020

[N,N-bis(1-methyl-2-benzimidazolyl)methyl-N-(bis-2-pyridylmethyl)amine] ( L 1 ) and [N,N-bis(2-quinolylmethyl)-N-bis(2-pyridyl)methylamine] ( L 2 ) were employed to prepare Cu II  and Cu I  complexes for spectroscopic and structural characterization. [ L 1 Cu II (H 2 O)](NO 3 ) 2 and [ L 2 Cu II (NO 3 )]NO 3 have Jahn-Teller distorted octahedral geometries, and give rise to isotropic EPR spectra in frozen solution. [ L 1 Cu I (CH 3 CN)]OTf and [ L 2 Cu I (CH 3 CN)]OTf have distorted trigonal bipyramidal and tetrahedral solid-state structures, respectively. The N-donors display labile behavior in solution, based on variable-temperature 1 H NMR studies. Addition of trimethylamine N-oxide (Me …