Lactams as prostanoid receptor ligands. Part 4: 2-Piperidones as selective EP4 receptor agonists.

2-Piperidones were prepared bearing heptanoic acid or a thioether heptanoic acid at the 1-position as well as appropriately substituted at the 6-position to mimic the structure of prostaglandins. The stereochemical purity at the 6-position was determined to be 95% ee for an advanced synthetic intermediate. The 2-piperidones were identified as potent agonists at the EP4 prostanoid receptor. They displayed a high affinity (Ki 5-130 nM) at EP4 and subtype selectivity.

Tweaking copper hydride (CuH) for synthetic gain. A practical, one-pot conversion of dialkyl ketones to reduced trialkylsilyl ether derivatives.

[reaction: see text] Variations in the reagents and stoichiometries used to generate CuH in situ, as well as the nature of the ligands present, have led to a very efficient and inexpensive method for effecting hydrosilylations of dialkyl ketones.