A primary goal of Phillip Crews' marine natural products research is to understand the chemistry of tropical marine sponges. Using bioassay-guided isolation assists us in the discovery of natural products potent against human diseases such as cancer or viruses. Our search for novel active compounds incorporates elements of structure elucidation but there are other dimensions to this research, including questions in the areas of chemical ecology, marine natural products biosynthesis, and the relationship between secondary metabolite chemistry and taxonomy.
Whenever possible, we try to use new concise strategies to elucidate structures, including gradient 2D NMR techniques such as HMBC, HMQC, COSY, TOCSY, NOESY, and 1H-15N HMQC. Utilization of new NMR hardware, 3mm probes and advanced NMR microtubes, nanoprobe, micro-coil flow probe and cryo probe technology on 500 and 600 MHz machines addresses problems of limited amounts of sample. Another goal is to engage in follow-up studies that employ molecular mechanics data combined with these state-of-the-art NMR techniques.