Solvent effects in the structure dereplication of caffeoyl quinic acids

The choice of solvent is an important but often neglected cofactor in the s tructure determination and compound dereplication of caffeoyl quinic acid d erivatives (CQAD). Both unforeseeable shift effects and substantial influen ces on molecular conformation caused by the various solvents lead to marked changes in the shifts and the coupling pattern. Therefore, the assignment of the relative stereochemistry of the cyclohexane ring substituents is com plicated and can be misleading, especially when relying on literature data. Both H-1 and C-13 Shift values were determined for prominent CQAD. Further more, the proton spin systems were fully analyzed in order to establish cha nges in molecular geometry that are due to solvent effects. Copyright (C) 1 999 John Wiley & Sons, Ltd.