REVISED STRUCTURES OF THE AZAFLUORENONE ALKALOIDS FROM GUAITERIA DIELSIANA

Abstract

The structures of three alkaloids isolated from Guatteria dielsiana, 6-methoxyonychine, dielsine and dielsinol, originally described as l-azafluoren-9-ones, are revised to 4-azafluoren-9-ones on the basis of previous synthetic work and current studies on alkaloids of the Annonaceae. Synthetic 6-methoxyonychine (6-methoxy-lmethyl- 4-azafluoren-9-one) is shown to be identical with the natural product.