10425-70-4Relevant articles and documents
Lewis Acidic Boranes, Lewis Bases, and Equilibrium Constants: A Reliable Scaffold for a Quantitative Lewis Acidity/Basicity Scale
Mayer, Robert J.,Hampel, Nathalie,Ofial, Armin R.
supporting information, p. 4070 - 4080 (2021/01/29)
A quantitative Lewis acidity/basicity scale toward boron-centered Lewis acids has been developed based on a set of 90 experimental equilibrium constants for the reactions of triarylboranes with various O-, N-, S-, and P-centered Lewis bases in dichloromethane at 20 °C. Analysis with the linear free energy relationship log KB=LAB+LBB allows equilibrium constants, KB, to be calculated for any type of borane/Lewis base combination through the sum of two descriptors, one for Lewis acidity (LAB) and one for Lewis basicity (LBB). The resulting Lewis acidity/basicity scale is independent of fixed reference acids/bases and valid for various types of trivalent boron-centered Lewis acids. It is demonstrated that the newly developed Lewis acidity/basicity scale is easily extendable through linear relationships with quantum-chemically calculated or common physical–organic descriptors and known thermodynamic data (ΔH (Formula presented.)). Furthermore, this experimental platform can be utilized for the rational development of borane-catalyzed reactions.
Annelated pyridines as highly nucleophilic and Lewis basic catalysts for acylation reactions
Tandon, Raman,Unzner, Teresa,Nigst, Tobias A.,De Rycke, Nicolas,Mayer, Peter,Wendt, Bernd,David, Olivier R. P.,Zipse, Hendrik
, p. 6435 - 6442 (2013/07/05)
New heterocyclic derivatives of 9-azajulolidine have been synthesized and characterized with respect to their nucleophilicity and Lewis basicity. The Lewis basicity of these bases as quantified through their theoretically calculated methyl-cation affinities correlate well with the experimentally measured reaction rates for addition to benzhydryl cations. All newly synthesized pyridines show exceptional catalytic activities in benchmark acylation reactions, which correlate only poorly with Lewis basicity or nucleophilicity parameters. A combination of Lewis basicity with charge and geometric parameters in the framework of a three-component quantitative structure-activity relationship (QSAR) model is, however, highly predictive. Copyright
Novel tricyclic inhibitors of 1κB kinase
Kempson, James,Spergel, Steven H.,Guo, Junqing,Quesnelle, Claude,Gill, Patrice,Belanger, Dominique,Dyckman, Alaric J.,Li, Tianle,Watterson, Scott H.,Langevine, Charles M.,Das, Jagabandhu,Moquin, Robert V.,Furch, Joseph A.,Marinier, Anne,Dodier, Marco,Martel, Alain,Nirschl, David,Van Kirk, Katy,Burke, James R.,Pattoli, Mark A.,Gillooly, Kathleen,McIntyre, Kim W.,Laishun, Chen,Zheng, Yang,Marathe, Punit H.,Wang-Iverson, David,Dodd, John H.,McKinnon, Murray,Barrish, Joel C.,Pitts, William J.
experimental part, p. 1994 - 2005 (2009/12/31)
The design and synthesis of a novel series of oxazole-, thiazole-, and imidazole-based inhibitors of IκB kinase (IKK) are reported. Biological activity was improved compared to the pyrazolopurine lead, and the expedient synthesis of the new tricyclic systems allowed for efficient exploration of structure-activity relationships. This, combined with an iterative rat cassette dosing strategy, was used to identify compounds with improved pharmacokinetic (PK) profiles to advance for in vivo evaluation.