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Abstract The design of catalysts for asymmetric propargylations remains a challenging task, with only a handful of methods providing access to enantioenriched homopropargylic alcohols. In this work, guided by previously reported computational predictions, a set of atropisomeric bipyridineN,N’‐dioxides was tested as Lewis base catalysts for the asymmetric propargylation of aldehydes with trichloroallenylsilane. The catalysts are easily prepared in four simple steps starting from readily available methyl ketones. Aryl‐substituted derivatives proved to be highly active and showed a high level of enantiocontrol even at 1 mol% loading. The reaction scope includes a wide range of aromatic, heteroaromatic, and unsaturated aldehydes. New computations confirm that the key stereodetermining transition state structures for the synthesized catalysts are similar to those previously reported for the model structure. magnified image 

Abstract There is an urgent need for new antibiotics to mitigate the existential threat posed by antibiotic resistance. Within the ketolide class, solithromycin has emerged as one of the most promising candidates for further development. Crystallographic studies of bacterial ribosomes and ribosomal subunits complexed with solithromycin have shed light on the nature of molecular interactions (π‐stacking and H‐bonding) between from the biaryl side‐chain of the drug and key residues in the 50S ribosomal subunit. We have designed and synthesized a library of solithromycin analogs to study their structure‐activity relationships (SAR) in tandem with new computational studies. The biological activity of each analog was evaluated in terms of ribosomal affinity (K_ddetermined by fluorescence polarization), as well as minimum inhibitory concentration assays (MICs). Density functional theory (DFT) studies of a simple binding site model identify key H‐bonding interactions that modulate the potency of solithromycin analogs.