1PPH:
reference: Geometry of binding of the N alpha-tosylated piperidides of m-amidino-, p-amidino- and p-guanidino phenylalanine to thrombin and trypsin. X-ray crystal structures of their trypsin complexes and modeling of their thrombin complexes., Turk D, Sturzebecher J, Bode W, FEBS Lett 1991 Aug 5;287(1-2):133-8. PMID: 1879520

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