3EQ7:
reference: Prolyl oligopeptidase inhibition by N-acyl-pro-pyrrolidine-type molecules., Kanai K, Aranyi P, Bocskei Z, Ferenczy G, Harmat V, Simon K, Batori S, Naray-Szabo G, Hermecz I, J Med Chem. 2008 Dec 11;51(23):7514-22. PMID: 19006380

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