A temperature-controlled mechanism switch between the Al(OTf)(3)-catalysed direct addition of alcohols or the Ferrier rearrangement reactions in some glycals is presented. The scope and limitations are investigated as are the influence of the stereochemistry and nature of the protecting groups on the glycal substrate.

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A BioFocus DPI SoftFocus library of ∼35 000 compounds was screened against Mycobacterium tuberculosis (Mtb) in order to identify novel hits with antitubercular activity. The hits were evaluated in biology triage assays to exclude compounds suggested to function via frequently encountered promiscuous mechanisms of action including inhibition of the QcrB subunit of the cytochrome bc1 complex, disruption of cell–wall homeostasis, and DNA damage. Among the hits that passed this screening cascade, a 6-dialkylaminopyrimidine carboxamide series was prioritized for hit to lead optimization. Compounds from this series were active against clinical Mtb strains, while no cross-resistance to conventional antituberculosis drugs was observed. This suggested a novel mechanism of action, which was confirmed by chemoproteomic analysis leading to the identification of BCG_3193 and BCG_3827 as putative targets of the series with unknown function. Initial structure–activity relationship studies have resulted in compounds with moderate to potent antitubercular activity and improved physicochemical properties.

3,4,6-Tri-O-acetyl-D-galactal is selectively converted into 1-O-aryl-2-deoxy derivatives or chiral bridged benzopyrans under Al(OTf)3 catalysis, depending on reaction conditions. The benzopyrans react with Al(OTf)3/acetic anhydride in ring-opening reactions in the absence or presence of acetic acid to selectively produce chiral chromenes or chromans, respectively, in high yields.

Amide functional groups are prominent in a broad range of organic compounds with diverse beneficial applications. In this work, we report the synthesis of these functional groups via an iron(iii) chloride-catalyzed direct amidation of esters. The reactions are conducted under solvent-free conditions and found to be compatible with a range of amine and ester substrates generating the desired amides in short reaction times and good to excellent yields at a catalyst loading of 15 mol%.