PDB-4jfl: Increasing the Efficiency Efficiency of Ligands for the FK506-Binding Protein 51 by Conformational Control: Complex of FKBP51 with 6-({(1S,5R)-3-[2-(3,4-dimethoxyphenoxy)ethyl]-2-oxo-3,9-diazabicyclo[3.3.1]non-9-yl}sulfonyl)-1,3-benzothiazol-2(3H)-one