1. Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822-2275, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853-1301, and Marine Ecology and Aquaculture Group, National Institute of Water and Atmospheric Research (NIWA), Taihoro Nukurangi, Private Bag 109-695 Newmarket, Auckland, New Zealand