Favorskii-Like Rearrangement of an Aliphatic α-Halo Amide

The Fascinating Chemistry of α-Haloamides

The aim of this review is to highlight the rich chemistry of α-haloamides originally mainly used to discover new C-N, C-O and C-S bond forming reactions, and later widely employed in C-C cross-coupling reactions with C(sp3), C(sp2) and C(sp) coupling partners. Radical-mediated transformations of α-haloamides bearing a suitable located unsaturated bond has proven to be a straightforward alternative to access diverse cyclic compounds by means of either radical initiators, transition metal redox catalysis or visible light photoredox catalysis. On the other hand, cycloadditions with α-halohydroxamate-based azaoxyallyl cations have garnered significant attention. Moreover, in view of the important role in life and materials science of difluoroalkylated compounds, a wide range of catalysts has been developed for the efficient incorporation of difluoroacetamido moieties into activated as well as unactivated substrates.

Synthesis and biological evaluation of Esaprazole analogues showing σ1 binding and neuroprotective properties in vitro

Esaprazole, a molecule previously acknowledged to protect against stomach and intestinal ulcers was surprisingly discovered to have neuroprotective activities and σ1 binding in vitro. A highly diverse set of Esaprazole analogues 2-5 was prepared in order to increase blood-brain barrier penetration. The analogues showed a structure-activity relationship at the σ1 receptor closely matching already published pharmacophores. Many of the analogues were shown to have neuroprotective properties in two assays using primary cultures of cortical neurons exposed to glutamate and hydrogen peroxide. However, no apparent SAR for these two assays could be developed. Metabolic stability of the analogues were also investigated and the structure of R(1) had a significant bearing on the ADME properties of the compound resulting in two series of compounds. Compounds in which R(1) was a H or acyl group had good metabolic stability in RLM but poor BBB penetration, whereas compounds where R(1) was a cyclo- or bicyclo-alkyl group had poor metabolic stability but good BBB penetration.