1. We gratefully acknowledge partial support of this work by the Public Health Service, Cancer Institute, Grant CA 11967-10. We also express our thanks to the National Science Foundation (Grant No. GP 17641) for supplemental support for the purchase of the XL-100 NMR spectrometer.
2. National Science Foundation Fellow 1971-1972, Summer 1973; present address, Cameron College, Lawton, Oklahoma;
3. Research Associate. 1971-73.
4. Research Associate. 1973-75.