4PM0:
reference: Discovery of 2-(Cyclopentylamino)thieno[3,2-d]pyrimidin-4(3H)-one Derivatives as a New Series of Potent Phosphodiesterase 7 Inhibitors., Kawai K, Endo Y, Asano T, Amano S, Sawada K, Ueo N, Takahashi N, Sonoda Y, Nagai M, Kamei N, Nagata N, J Med Chem. 2014 Nov 19. PMID: 25383422

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