3BJC:
reference: An insight into the pharmacophores of phosphodiesterase-5 inhibitors from synthetic and crystal structural studies., Chen G, Wang H, Robinson H, Cai J, Wan Y, Ke H, Biochem Pharmacol. 2008 May 1;75(9):1717-28. Epub 2008 Feb 12. PMID: 18346713

This OCA Structure page
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