Acknowledgments. This work was done in the laboratory of Dr. Ivan D. Frantz, .Jr. The author wishes to thank Dr. Raymond Dodson and Dr. Robert Riddle of the Chemistry Department, Universii y of Minnesota for helpful discussions. The IH-NMR spectrum was obtained by Mr. Robert Thrift, Freshwater Biological Institute, University of Minnesota and the ',IC-NMR measurements were performed by Lenas He- ... References and Notes (a) This work was supported by ...