1. Department of Chemistry and Biochemistry and SSPPS, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093, University of California, Davis, 1 Shields Avenue, Davis, California 95616, and Department of Biology and Marine Biology, Center for Marine Science, University of North Carolina Wilmington, 5600 Marvin K. Moss Lane, Wilmington, North Carolina 28403-3297