<b>Proximity Effects. XXXII. Ring Opening of <b><i>cis</i></b>- and <b><i>trans</i></b>-Cycloöctene Oxide in Alumina-catalyzed and Uncatalyzed Pyrolysis and in Reaction with Magnesium Bromide Etherate</b>
report the discovery of a series of JAK1-selective kinaseinhibitors with high potency and excellent JAK family subtype selectivity. A fragment screening hit 1 with a pyrazolopyridone core and a JAK1 bias was selected as the starting point for our fragment-based lead generation efforts. A two-stage strategy was chosen with the dual aims of improving potency and JAK1 selectivity: Optimization of the lipophilic