Recent advancements in iodide/phosphine-mediated photoredox radical reactions

• Tinglan Liu,
• Yu Zhou,
• Junhong Tang and
• Chengming Wang

Beilstein J. Org. Chem. 2023, 19, 1785–1803, doi:10.3762/bjoc.19.131

• the ability to be readily transformed into various valuable functional molecules, including amines, hydrazines, and nitrogen-containing heterocycles [13]. In a significant advancement in 2021, Lopchuk et al. revealed a novel method for the photodecarboxylative alkylation of diazirines 12 using the

• . Photodecarboxylative alkylation of redox-active esters with diazirines. Photoinduced iodine-anion-catalyzed decarboxylative/deaminative C–H alkylation of enamides. Photocatalytic C–H alkylation of coumarins mediated by NaI/PPh3 catalysis. Photoredox alkylation of aldimines by NaI/PPh3 catalysis. Photoredox C–H

Diazirine-functionalized mannosides for photoaffinity labeling: trouble with FimH

• Femke Beiroth,
• Tomas Koudelka,
• Thorsten Overath,
• Stefan D. Knight,
• Andreas Tholey and
• Thisbe K. Lindhorst

Beilstein J. Org. Chem. 2018, 14, 1890–1900, doi:10.3762/bjoc.14.163

• accuracy. We are concluding from this study that photolabeling of FimH with sugar diazirines has only very limited success and cannot be regarded a facile approach for covalent modification of FimH. Keywords: diazirines; docking; FimH; lectin ligands; mannosides; mass spectrometry; photoaffinity labelling

• ) and irradiation of the ligand–protein complex to form an excited intermediate, which eventually leads to a covalently crosslinked ligand–receptor conjugate, which has to be identified by mass spectrometry (Figure 1). Three widely used photoreactive groups are aryl azides, benzophenones and diazirines

• . They differ with respect to their steric properties, photochemistry, and reactivity. In order to be applied in a biological environment, the wavelength of the light required for activation of the photolabile ligand has to be biocompatible. Furthermore, small photophores are desirable. Diazirines meet

Total synthesis and cytotoxicity of the marine natural product malevamide D and a photoreactive analog

• Werner Telle,
• Gerhard Kelter,
• Heinz-Herbert Fiebig,
• Peter G. Jones and
• Thomas Lindel

Beilstein J. Org. Chem. 2014, 10, 316–322, doi:10.3762/bjoc.10.29

• the photoreactive derivative proved to be less active by a factor of at least 200. COMPARE analysis indicated tubulin interaction as likely mode of action of malevamide D. Keywords: cytotoxicity; diazirines; dolastatin analogs; marine natural products; peptides; total synthesis; Introduction The

En route to photoaffinity labeling of the bacterial lectin FimH

• Thisbe K. Lindhorst,
• Michaela Märten,
• Andreas Fuchs and
• Stefan D. Knight

Beilstein J. Org. Chem. 2010, 6, 810–822, doi:10.3762/bjoc.6.91

• shown both by MS/MS studies and by affino dot–blot analysis. Keywords: diazirines; FimH; lectins; MS/MS analysis; photoactive mannoside ligands; photoaffinity labeling; Introduction Photoaffinity labeling is a technique by which ligand binding sites of a receptor protein can be identified in solution

• photoaffinity-labeling of FimH. Our earlier work suggested that diazirines are more useful photoactive groups than aryl azides and benzophenones [15]. Therefore, the synthesis of a biotin-labeled daizirine-functionalized mannoside was our next target. In this synthesis, aspartic acid was utilized as the

• angiotensin II demonstrated, that the synthesized diazirines are well suited as photoprobes for the labeling of this peptide, with a preference for the tyrosine side chain. Thus, the photoactive mannosides were next investigated with the bacterial lectin FimH. For the irradiation experiments a FimH truncate