293294-71-0Relevant articles and documents
Effect of a halogenide substituent on the stability and photophysical properties of lanthanide triple-stranded helicates with ditopic ligands derived from bis(benzimidazolyl)pyridine
Iglesias, Carlos Platas,Elhabiri, Mourad,Hollenstein, Marcel,Buenzli, Jean-Claude G.,Piguet, Claude
, p. 2031 - 2043 (2000)
Bis {1-ethyl-2-[6-(N,N-diethylcarbamoyl)-4-halogenopyridin-2-yl]benzimidazol-5-yl} methane (halogeno = chloro, LE; bromo, LF) have been synthesized as ditopic receptors for the development of lanthanide-containing helicates able to couple with biological material and to test the influence of the halogeno substituent on the wrapping process, the structure of the resulting dimetallic edifices, and the photophysical properties of the encapsulated ions. The stability of the [Eu2(L)3]6+ helicates, as determined by NMR competitive titrations, decreases by respectively one (LF) and three (LE) orders of magnitude compared to the value found for the unsubstituted ligand (LB) although it remains large, log β23 = 23.8 (LF) and 21.8 (LE) in acetonitrile. The [Ln2(LE)3]6+ helicates are shown to be isostructural in acetonitrile over the lanthanide series (Pr to Yb) and the crystal structure of [Tb2(LB)3]6+ appears to be a good model for their solution structure, as demonstrated by paramagnetic NMR measurements (lanthanide induced shift method) and relaxation time determination. Ligand LE appears to be a fair sensitiser of EuIII, the quantum yield of [Eu2(LE)3]6+ being 25% larger than that found for [Eu2(LB)3]6+, but the ligand 3ππ* state and Tb(5D4) excited level are in resonance, which limits the sensitisation of TbIII. High resolution luminescence spectra of [Eu2(LE)3]6+, both in solution and in the solid state, are presented and discussed in terms of site symmetry and vibronic coupling mechanisms. The Royal Society of Chemistry 2000.
PI3K-α INHIBITORS AND METHODS OF USE THEREOF
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Paragraph 1046, (2021/11/06)
The present disclosure relates to novel compounds and pharmaceutical compositions thereof, and methods for inhibiting the activity of PI3K-α enzymes with the compounds and compositions of the disclosure. The present disclosure further relates to, but is n
Scale-up of flow-assisted synthesis of C2-symmetric chiral PyBox ligands
Battilocchio, Claudio,Baumann, Marcus,Baxendale, Ian R.,Biava, Mariangela,Kitching, Matthew O.,Ley, Steven V.,Martin, Rainer E.,Ohnmacht, Stephan A.,Tappin, Nicholas D. C.
, p. 635 - 647 (2012/04/17)
A series of PyBox ligands were prepared from commercially available chelidonic acid by a multistep flow sequence using mesoreactor technology. A chloro group introduced onto the ligand scaffold was subsequently exploited to give amine derivatives ready for immobilization through microencapsulation technologies. Georg Thieme Verlag Stuttgart · New York.
Significance of interactions of BACE1-Arg235 with its ligands and design of BACE1 inhibitors with P2 pyridine scaffold
Hamada, Yoshio,Ohta, Hiroko,Miyamoto, Naoko,Sarma, Diganta,Hamada, Takashi,Nakanishi, Tomoya,Yamasaki, Moe,Yamani, Abdellah,Ishiura, Shoichi,Kiso, Yoshiaki
scheme or table, p. 2435 - 2439 (2009/12/25)
Recently, we reported potent substrate-based pentapeptidic BACE1 inhibitors possessing a hydroxymethylcarbonyl isostere as a substrate transition-state mimic. Because these inhibitors contained some natural amino acids, we would need to improve their enzymatic stability in vivo and permeability across the blood-brain barrier, so that they become practically useful. Subsequently, non-peptidic and small-sized BACE1 inhibitors possessing a heterocyclic scaffold, 2,6-pyridenedicarboxylic, chelidamic or chelidonic moiety, at the P2 position were reported. These inhibitors were designed based on the conformer of docked inhibitor in BACE1. In this study, we discuss the role and significance of interactions between Arg235 of BACE1 and its inhibitor in BACE1 inhibitory mechanism. Moreover, we designed more potent small-sized BACE1 inhibitors with a 2,6-pyridinedicarboxylic scaffold at the P2 position, that were optimized for the interactions with Arg235 of BACE1.
