Evidence from the solubility, 2D-NOESY results and ITC analysis suggest that encapsulation and electrostatic interaction together caused the solubility enhancement of phenylbutazone.
The relative stereochemistry of the 1, 10-double bond and that of the methoxyl, methyl, and acetoxy groups were determined by NOESY experiments and analyses of the coupling constants.
The sequence-specific assignment of spin systems was obtained by noes correlation in wet-noesy spectra and the complete assignment of proton resonances for backbone and side chain has been achieved.