CRYSTAL AND MOLECULAR STRUCTURE OF PIQUEROL A A POTENT GROWTH-INHIBITING FACTOR
Crystal and molecular structure of piquerol A isolated from Piqueria trinervia Cav was determined. The X-ray study confirms that in the solid-state the structure of piquerol A is similar to that inferred from NMR spectra. The isopropenyl group is planar and makes approximately 38.4° with the mean plane for the six-membered ring. The two hydroxyl groups are above the plane through the six-membered ring, while the C4 and H5 are below this plane.