The author of 《1-Picolinyl-5-azido Thiosialosides: Versatile Donors for the Stereoselective Construction of Sialyl Linkages》 were Chen, Jian; Hansen, Thomas; Zhang, Qing-Ju; Liu, De-Yong; Sun, Yao; Yan, Hao; Codee, Jeroen D. C.; Schmidt, Richard R.; Sun, Jian-Song. And the article was published in Angewandte Chemie, International Edition in 2019. Computed Properties of C6H7Br2N The author mentioned the following in the article:
With the picolinyl (Pic) group as a C-1 located directing group and N3 as versatile precursor for C5-NH2, a novel 1-Pic-5-N3 thiosialyl donor was designed and synthesized, based on which a new sialylation protocol was established. In comparison to conventional sialylation methods, the new protocol exhibited obvious advantages, including excellent α-stereoselectivity in the absence of a solvent effect, broad substrate scope encompassing the challenging sialyl 8- and 9-hydroxy groups of sialic acid acceptors, flexibility in sialoside derivative synthesis, high temperature tolerance and easy scalability. In particular, the applicability to the synthesis of complex and bioactive N-glycan antennae when combined with the MPEP glycosylation protocol via the “”latent-active”” strategy has been shown. Mechanistically, the excellent α-stereoselectivity of the novel sialylation protocol could be attributed to the dramatic electron-withdrawing effect of the protonated Pic groups, which was supported by control reactions and DFT calculations After reading the article, we found that the author used 2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8Computed Properties of C6H7Br2N)
2-(Bromomethyl)pyridine hydrobromide(cas: 31106-82-8) belongs to pyridine. Pyridine is very deactivated towards electrophilic substitution with respect to benzene. For this reason classical formylation, using methods such as the Gattermann or Vilsmeier reactions, are not generally successful. Computed Properties of C6H7Br2N