.S., Waldmann, H. and Whitesides, G. M., Chem. Britain, 1987, 23, 645-654. 203. "The Enantiomeric Purity of Polar Substrates Can Be Determined with Chiral Lanthanide NMR Shift Reagents in Polar Solvents", Sweeting, L. M., Crans, D. C. and Whitesides, G. M., J. Org. Chem., 1987, 52, 2273-2276. 202. "Fumarase-Cataly