Application of REDOR NMR in natural product chemistry

Many natural products have molecular targets that are non-crystalline and insoluble biological matrices, such as proteins embedded in lipid membrane, cell membranes, and cell walls. To understand the action mechanisms, it is essential to determine the binding structure with atomic-level resolution. For structural studies of biological solids, high resolution distance measurements using solid-state nuclear magnetic resonance (NMR) are indispensable techniques, of which rotational-echo double-resonance (REDOR) is one of the most widely used methods. This feature article introduces the basic concepts of REDOR NMR and its application to the structural study of natural products in biological matrices.