Nuclear Magnetic Resonance Spectroscopy of Chlorophylls and Corrins

The role of NMR in the study of compounds of biological importance is widely recognized and appreciated. There can be few categories of such substances, however, to which NMR has made such substantive contributions as it has to the understanding of the chlorophylls and the corrins. The chlorophylls are indispensible agents in the conversion of the energy of light to chemical oxidizing and reducing capacity. The natural corrins are coenzymes for a number of enzyme systems involved in important isomerization and methyl group transfer reactions, and are intimately involved in protein and probably also in lipid and carbohydrate metabolism. Vitamin B12 plays a very important part in hemopoiesis (stimulation of red blood cell formation), and together with folic acid participates in the formation of deoxyribonucleotides from ribonucleotides. Applied to the chlorophylls, NMR has provided information relevant to such aspects as the sites of exchangeable hydrogen, keto-enol tautomerism, the biosynthetic pathways of