2V35:
reference: The efficiency of C-4 substituents in activating the beta-lactam scaffold towards serine proteases and hydroxide ion., Mulchande J, Martins L, Moreira R, Archer M, Oliveira TF, Iley J, Org Biomol Chem. 2007 Aug 21;5(16):2617-26. PMID: 18019537

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