Identification of 4-benzylamino-2-[(4-morpholin-4-ylphenyl)amino]pyrimidine-5-carboxamide derivatives as potent and orally bioavailable STAT6 inhibitors.
Nagashima S, Nagata H, Iwata M, Yokota M, Moritomo H, Orita M, Kuromitsu S, Koakutsu A, Ohga K, Takeuchi M, Ohta M, Tsukamoto S.
Signal transducers and activators of transcription 6 (STAT6) is a key regulator of the type 2 helper T (Th2) cell immune response and a potential therapeutic target for allergic diseases such as asthma and atopic diseases. To search for potent and orally bioavailable STAT6 inhibitors, we synthesized a series of 4-benzylaminopyrimidine-5-carboxamide derivatives and evaluated their STAT6 inhibitory activities. Among these compounds, 2-[(4-morpholin-4-ylphenyl)amino]-4-[(2,3,6-trifluorobenzyl)amino]pyrimidine-5-carboxamide (25y, YM-341619, AS1617612) showed potent STAT6 inhibition with an IC(50) of 0.70nM, and also inhibited Th2 differentiation in mouse spleen T cells induced by interleukin (IL)-4 with an IC(50) of 0.28 nM without affecting type 1 helper T (Th1) cell differentiation induced by IL-12. In addition, compound 25y showed an oral bioavailability of 25% in mouse.