Identification and Characterization of Small Molecules as Potent and Specific EPAC2 Antagonists
作者:Haijun Chen、Tamara Tsalkova、Oleg G. Chepurny、Fang C. Mei、George G. Holz、Xiaodong Cheng、Jia Zhou
DOI:10.1021/jm3014162
日期:2013.2.14
EPAC1 and EPAC2, two isoforms of exchange proteins directly activated by cAMP (EPAC), respond to the second messenger cAMP and regulate a wide variety of intracellular processes under physiological and pathophysiological circumstances. Herein, we report the chemical design, synthesis, and pharmacological characterization of three different scaffolds (diarylsulfones, N,N-diarylamines, and arylsulfonamides) as highly potent and selective antagonists of EPAC2. Several selective EPAC2 antagonists have been identified including 20i (HJC0350), which has an apparent IC50 of 0.3 mu M for competing with 8-NBD-cAMP binding of EPAC2 and is about 133-fold more potent than cAMP. Compounds 1 (ESI-05), 14c (HJC0338), and 20i, selected from each series, have exhibited no inhibition of EPAC1-mediated Rap1-GDP exchange activity at 25 mu M, indicating that they are EPAC2-specific antagonists. Moreover, live-cell imaging studies using EPAC1, EPAC2, or PICA FRET sensor also demonstrate that 20i functions as an EPAC2 specific antagonist.