Catalytic 1,2-dihydronaphthalene and <i>E</i>-aryl-diene synthesis <i>via</i> Co<sup>III</sup>–Carbene radical and <i>o</i>-quinodimethane intermediates
作者:Colet te Grotenhuis、Braja G. Das、Petrus F. Kuijpers、Wouter Hageman、Mees Trouwborst、Bas de Bruin
DOI:10.1039/c7sc03909c
日期:——
yields for substrates with an R2 = COOEt substituent at the vinylic position (~70-90% ). Changing the R2 moiety from an ester to other substituents has a surprisingly large influence on the (isolated) yields. This behaviour is unexpected for a radical rebound ring-closure mechanism, and points to a mechanism proceeding via ortho-quinodimethane (o-QDM) intermediates. Furthermore, substrates with an alkyl
The invention is directed to compounds that are prodrugs containing a chemical delivery system (CDS) moiety and a cysteine protease inhibitor moiety. The CDS moiety targets the prodrug to the brain or central nervous system. The cysteine protease inhibitor inhibits cysteine proteases upon release from the prodrug. Cysteine protease inhibitors are effective for treating dementia, Alzheimer's disease and vascular dementia. Targeting the brain or central nervous system offers significant advantages in treating these conditions and diseases. A preferred CDS prodrug is a dihydrotrigoneline CDS moiety coupled to an epoxysuccinyl peptide cysteine protease inhibitor moiety.
multisubstituted 1,3‐dienes by α‐exclusive alkylidenation of crotonic derivatives has been developed. This protocol, mediated by titanium tetrachloride chelation, features excellent regio‐ and stereoselectivity, mild reaction conditions, easy operation and wide substrate scope. Conversions of the derived dienes to other useful molecules were also explored.