1H1B:
reference: Discovery of further pyrrolidine trans-lactams as inhibitors of human neutrophil elastase (HNE) with potential as development candidates and the crystal structure of HNE complexed with an inhibitor (GW475151)., Macdonald SJ, Dowle MD, Harrison LA, Clarke GD, Inglis GG, Johnson MR, Shah P, Smith RA, Amour A, Fleetwood G, Humphreys DC, Molloy CR, Dixon M, Godward RE, Wonacott AJ, Singh OM, Hodgson ST, Hardy GW, J Med Chem 2002 Aug 29;45(18):3878-90. PMID: 12190311

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