2192-33-8Relevant articles and documents
Azoacetylenes for the Synthesis of Arylazotriazole Photoswitches
Anderl, Felix,Balkenhohl, Moritz,Carreira, Erick M.,Fink, Moritz,Pfaff, Patrick
supporting information, p. 14495 - 14501 (2021/09/18)
We report a modular approach toward novel arylazotriazole photoswitches and their photophysical characterization. Addition of lithiated TIPS-acetylene to aryldiazonium tetrafluoroborate salts gives a wide range of azoacetylenes, constituting an underexplored class of stable intermediates.In situdesilylation transiently leads to terminal arylazoacetylenes that undergo copper-catalyzed cycloadditions (CuAAC) with a diverse collection of organoazides. These include complex molecules derived from natural products or drugs, such as colchicine, taxol, tamiflu, and arachidonic acid. The arylazotriazoles display near-quantitative photoisomerization and long thermalZ-half-lives. Using the method, we introduce for the first time the design and synthesis of a diacetylene platform. It permits implementation of consecutive and diversity-oriented approaches linking two different conjugants to independently addressable acetylenes within a common photoswitchable azotriazole. This is showcased in the synthesis of several photoswitchable conjugates, with potential applications as photoPROTACs and biotin conjugates.
Inhibition of the Cysteine Protease Human Cathepsin L by Triazine Nitriles: Amide???Heteroarene π-Stacking Interactions and Chalcogen Bonding in the S3 Pocket
Giroud, Maude,Ivkovic, Jakov,Martignoni, Mara,Fleuti, Marianne,Trapp, Nils,Haap, Wolfgang,Kuglstatter, Andreas,Benz, J?rg,Kuhn, Bernd,Schirmeister, Tanja,Diederich, Fran?ois
supporting information, p. 257 - 270 (2017/02/15)
We report an extensive “heteroarene scan” of triazine nitrile ligands of the cysteine protease human cathepsin L (hCatL) to investigate π-stacking on the peptide amide bond Gly67–Gly68 at the entrance of the S3 pocket. This heteroarene???peptide bond stacking was supported by a co-crystal structure of an imidazopyridine ligand with hCatL. Inhibitory constants (Ki) are strongly influenced by the diverse nature of the heterocycles and specific interactions with the local environment of the S3 pocket. Binding affinities vary by three orders of magnitude. All heteroaromatic ligands feature enhanced binding by comparison with hydrocarbon analogues. Predicted energetic contributions from the orientation of the local dipole moments of heteroarene and peptide bond could not be confirmed. Binding of benzothienyl (Ki=4 nm) and benzothiazolyl (Ki=17 nm) ligands was enhanced by intermolecular C?S???O=C interactions (chalcogen bonding) with the backbone C=O of Asn66 in the S3 pocket. The ligands were also tested for the related enzyme rhodesain.
A Fluorine-Containing Cryptand for the Complexation of Anions and the Utility of 19F NMR Spectroscopy for the Determination of Host-Guest Association
Plenio, Herbert,Diodone, Ralph
, p. 1075 - 1078 (2007/10/02)
The first fluorine-containing cryptand F3-TREN 4 for the complexation of anions was prepared in the 3 + 2-condensation reaction of 2-fluoro-1,3-phthalaldehyde 3 with tris(2-aminoethyl)amine and subsequent reduction with NaBH4.Upon incorporation of anionic guests 4*6HClO4 experiences shifts of its 19F NMR resonances and thus demonstrates the advantages of studying host-guest association by 19F NMR spectroscopy. - Keywords: Macrocycles, 19F NMR Spectra, Fluorine, Anion Complexation
