3ZPQ:
reference: Biophysical fragment screening of the beta1-adrenergic receptor: Identification of high affinity aryl piperazine leads using structure-based drug design., Christopher J, Brown J, Dore A, Errey J, Koglin M, Marshall FH, Myszka D, Rich RL, Tate CG, Tehan B, Warne T, Congreve M, J Med Chem. 2013 Mar 21. PMID: 23517028

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