1N1L:
reference: Pyrrolidine-5,5-trans-lactams. 2. The use of X-ray crystal structure data in the optimization of P3 and P4 substituents., Andrews DM, Chaignot H, Coomber BA, Good AC, Hind SL, Johnson MR, Jones PS, Mills G, Robinson JE, Skarzynski T, Slater MJ, Somers DO, Org Lett 2002 Dec 12;4(25):4479-82. PMID: 12465917

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