42521-09-5Relevant articles and documents
Evidence of crystal packing effects in stabilizing high or low spin states of iron(ii) complexes with functionalized 2,6-bis(pyrazol-1-yl)pyridine ligands
Bridonneau, Nathalie,Rigamonti, Luca,Poneti, Giordano,Pinkowicz, Dawid,Forni, Alessandra,Cornia, Andrea
, p. 4075 - 4085 (2017)
The molecular structures and magnetic properties of homoleptic iron(ii) compounds [Fe(bpp-COOMe)2](ClO4)2 (1) and [Fe(bpp-triolH3)2](ClO4)2 (2) have been investigated to ascertain their spin crossover (SCO) behaviour. In these hexacoordinated complexes, the bpp (2,6-bis(pyrazol-1-yl)pyridine) ligands adopt a mer-mer coordination mode and carry COOMe or C(O)NHC(CH2OH)3para substituents, respectively, on the central pyridyl ring. In spite of the almost equal donor power of the ligands to the iron(ii) centre, the two compounds feature different spin state configurations at room temperature. Compound 1 displays a highly-distorted octahedral environment around the iron(ii) centre, which adopts a high spin (HS) state at all temperatures, even under an external applied pressure up to 1.0 GPa. By contrast, 2 is characterized by a more regular octahedral coordination around the metal ion and exhibits a low spin (LS) configuration at or below room temperature. However, it shows a thermally-induced SCO behaviour at T > 400 K, along with Light-Induced Excited Spin State Trapping (LIESST) at low temperature, with TLIESST = 38 K. Since DFT (U)M06/6-311+G(d) geometry optimizations in vacuo indicate that both complexes should adopt a HS state and a highly-distorted coordination geometry, the stabilization of a LS configuration in 2 is ultimately ascribed to the effect of intermolecular hydrogen bonds, which align the [Fe(bpp-triolH3)2]2+ cations in 1D chains and impart profound differences in the geometric arrangement of the ligands.
FUSED HETEROCYCLIC COMPOUNDS AS CAM KINASE INHIBITORS
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Paragraph 1335; 1336, (2018/06/09)
The present disclosure relates to compounds that are CaM Kinase inhibitors and to their use in the treatment of various disease states, including atrial fibrillation and myocardial infarction. In particular embodiments, the general structure of the compounds is given by Formula I: wherein R1, R2, R3, R4, R5, R6, R9 and R10 are as described herein, to methods for the preparation and use of the compounds and to pharmaceutical compositions containing the same.
Practical Synthesis of a S1P Receptor 1 Agonist via a Guareschi-Thorpe Reaction
Schmidt, Gunther,Bolli, Martin H.,Lescop, Cyrille,Abele, Stefan
, p. 1637 - 1646 (2016/09/23)
A practical synthesis of S1P receptor 1 agonist ACT-334441 (1) through late-stage convergent coupling of two key intermediates is described. The first intermediate is 2-cyclopentyl-6-methoxyisonicotinic acid whose skeleton was built from 1-cyclopentylethanone, ethyl oxalate, and cyanoacetate in a Guareschi-Thorpe reaction in 42% yield over five steps. The second, chiral intermediate, is a phenol ether derived from enantiomerically pure (R)-isopropylidene glycerol ((R)-solketal) and 3-ethyl-4-hydroxy-5-methylbenzonitrile in 71% yield in a one-pot reaction. The overall sequence entails 18 chemical steps with 10 isolated intermediates. All raw materials are cheap and readily available in bulk quantities, the reaction conditions match with standard pilot plant equipment, and the route reproducibly afforded 3-20 kg of 1 in excellent purity and yield for clinical studies.
