2P8S:
reference: Rational design of a novel, potent, and orally bioavailable cyclohexylamine DPP-4 inhibitor by application of molecular modeling and X-ray crystallography of sitagliptin., Biftu T, Scapin G, Singh S, Feng D, Becker JW, Eiermann G, He H, Lyons K, Patel S, Petrov A, Sinha-Roy R, Zhang B, Wu J, Zhang X, Doss GA, Thornberry NA, Weber AE, Bioorg Med Chem Lett. 2007 Apr 2;. PMID: 17433672

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