17193-39-4Relevant articles and documents
Structure-Based Design of Inhibitors Selective for Human Proteasome β2c or β2i Subunits
Xin, Bo-Tao,Huber, Eva M.,De Bruin, Gerjan,Heinemeyer, Wolfgang,Maurits, Elmer,Espinal, Christofer,Du, Yimeng,Janssens, Marissa,Weyburne, Emily S.,Kisselev, Alexei F.,Florea, Bogdan I.,Driessen, Christoph,Van Der Marel, Gijsbert A.,Groll, Michael,Overkleeft, Herman S.
supporting information, p. 1626 - 1642 (2019/02/19)
Subunit-selective proteasome inhibitors are valuable tools to assess the biological and medicinal relevance of individual proteasome active sites. Whereas the inhibitors for the β1c, β1i, β5c, and β5i subunits exploit the differences in the substrate-binding channels identified by X-ray crystallography, compounds selectively targeting β2c or β2i could not yet be rationally designed because of the high structural similarity of these two subunits. Here, we report the development, chemical synthesis, and biological screening of a compound library that led to the identification of the β2c- and β2i-selective compounds LU-002c (4; IC50 β2c: 8 nM, IC50 β2i/β2c: 40-fold) and LU-002i (5; IC50 β2i: 220 nM, IC50 β2c/β2i: 45-fold), respectively. Co-crystal structures with β2 humanized yeast proteasomes visualize protein-ligand interactions crucial for subunit specificity. Altogether, organic syntheses, activity-based protein profiling, yeast mutagenesis, and structural biology allowed us to decipher significant differences of β2 substrate-binding channels and to complete the set of subunit-selective proteasome inhibitors.
Aromatic Interactions in Organocatalyst Design: Augmenting Selectivity Reversal in Iminium Ion Activation
Holland, Mareike C.,Metternich, Jan Benedikt,Daniliuc, Constantin,Schweizer, W. Bernd,Gilmour, Ryan
supporting information, p. 10031 - 10038 (2015/07/07)
Substituting N-methylpyrrole for N-methyindole in secondary-amine-catalysed Friedel-Crafts reactions leads to a curious erosion of enantioselectivity. In extreme cases, this substrate dependence can lead to an inversion in the sense of enantioinduction. Indeed, these closely similar transformations require two structurally distinct catalysts to obtain comparable selectivities. Herein a focussed molecular editing study is disclosed to illuminate the structural features responsible for this disparity, and thus identify lead catalyst structures to further exploit this selectivity reversal. Key to effective catalyst re-engineering was delineating the non-covalent interactions that manifest themselves in conformation. Herein we disclose preliminary validation that intermolecular aromatic (CH-π and cation-π) interactions between the incipient iminium cation and the indole ring system is key to rationalising selectivity reversal. This is absent in the N-methylpyrrole alkylation, thus forming the basis of two competing enantio-induction pathways. A simple L-valine catalyst has been developed that significantly augments this interaction.
Rhodium/graphite-catalyzed hydrogenation of carbocyclic and heterocyclic aromatic compounds
Falini, Giuseppe,Gualandi, Andrea,Savoia, Diego
experimental part, p. 2440 - 2446 (2010/02/27)
Rhodium on graphite (Rh/Gr, C24Rh) was prepared by reaction of anhydrous rhodium trichloride with potassium graphite (C8K, 3 equivalents) and used as a heterogeneous catalyst for the hydrogenation of carbocyclic and heterocyclic aromatic compounds at room temperature and 1 atm of hydrogen pressure. The effect of substitution on the benzene ring was examined in a variety of derivatives, including those with alkyl, hydroxy, alkoxy, aryloxy, carboxy, amino, nitro, acyl, chloro, or functionalized alkyl groups. Reduction of carbonyl functions of aromatic aldehydes and ketones occurred with complete or partial cleavage of the benzylic C-O bond; this cleavage also occurred in the hydrogenation of benzylic alcohols and esters. Georg Thieme Verlag Stuttgart.
