Modern NMR Approaches to the Structure Elucidation of Natural Products: Volume 2: Data Acquisition and Applications to Compound Classes

The Ghanian plant Cryptolepis sanguinolenta is the source of a series of fascinating indoloquinoline alkaloids. The most unusual member of this alkaloid series was initially proposed to be a spiro nonacyclic structure, named cryptospirolepine, and was elucidated in 1993 based on the technologies available at that time. There were, however, several annoying attributes to the structure that bothered analysts for the ensuing 22 years. During the two decades that followed the initial work there...