Rp-8-CPT-cAMP is a structural combination of the lipophilic and non-hydrolyzable cAMP analogs, 8-CPT-cyclicAMP and Rp-cyclicAMPS .[1] It functions as a site-selective inhibitor of protein kinase A (PKA) type I and II, with preference towards site A of type I and site B of type II.2 By occupying cAMP binding sites at the regulatory subunit of PKA, Rp-8-CPT-cAMP prevents the kinase holoenzyme from dissociative activation.[2],[3]