Krista Suta

Study on Synthesis of N-Protected 2-Triazolyl Azetidines

Azetidine derivatives are interesting scaffolds in terms of medicinal chemistry. They can be regarded as structural homologs of aziridines. Herein we report synthetic approach to the novel N-protected 2-triazolyl azetidines which are structurally similar to our previously described aziridine derivatives with matrix metalloproteinase-2 inhihbitory activities. The synthetic rout includes ring closing of ethyl 2,4-dibromobutanoate, selective reduction of ester to aldehyde and transformation of the latter to terminal alkyne by Ohira-Bestmann reagent. 2-Ethynyl azetidines as key intermediates were transformed into triazole derivatives by Cu(I) catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction.

Modern approaches for SO 2 insertion in heterocyclic synthesis (microreview)

The most recent advances in the synthesis of heterocyclic compounds via insertion of sulfur dioxide reported from 2015 to 2018 are summarized. Methods described here are organized in several sections depending on the source of SO2: sodium or potassium metabisulfite (M2S2O5), SO2 adducts with nitrogen-containing heterocycles DABSO and DMAP·SO2, ex situ formed SO2, and intramolecularly released SO2.