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9-Substituted 2-chloro-6-sulfonylpurines provide 6-azido-2-sulfonylpurine derivatives with 61-83% yields when treated with sodium azide. Under optimized reaction conditions, the title compounds are obtained in a one-pot process, which involves a sequential treatment of 2,6-dichloropurines with a selected sodium sulfinate and sodium azide. Such a sulfonyl group dance (functional group swap) results from a cascade of S

2,6-Bis-(1,2,3-triazol-1H-1-yl)purine nucleosides react at C(6) with the N- and S-termini of various amino acids by expelling the corresponding 1,2,3-triazole as a leaving group in nucleophilic aromatic substitution reaction. This gives rise to a novel type of conjugate between purine nucleosides and amino acids. The obtained amino acid—derived 6-amino-2-(1,2,3-triazol-1H-1-yl)-purine derivatives showed useful levels of fluorescence with quantum yields up to 38% and Stokes shifts up to 91 nm. Glutathione and a cysteine-containing nonapeptide selectively reacted with their S-termini and produced the expected C(6) conjugates in good to excellent yields.

The synthesis of a set of cobalt(III)-complexes equipped with trisubstituted chiral cyclopentadienyl ligands is reported, and their steric and electronic parameters are mapped. The application potential of these complexes for asymmetric C-H functionalizations with 3d-metals is shown by the synthesis of dihydroisoquinolones from N-chlorobenzamides with a broad range of alkenes. The transformation proceeds with excellent enantioselectivities of up to 99.5:0.5 er and high regioselectivities. The observed values outperform the best rhodium(III)-based methods for this reaction type. Moreover, challenging substrates such as alkyl alkenes also react with high regio- and enantioselectivities.