The structure of zetekitoxin AB, a saxitoxin analog from the Panamanian golden frog Atelopus zeteki: a potent sodium-channel blocker.

ABSTRACT: Bufonid anurans of the genus Atelopus contain both steroidal bufadienolides and various guanidinium alkaloids of the tetrodotoxin class. The former inhibit sodium-potassium ATPases, whereas the latter block voltage-dependent sodium channels. The structure of one guanidinium alkaloid, zetekitoxin AB, has remained a mystery for over 30 years. The structure of this alkaloid now has been investigated with a sample of approximately 0.3 mg, purified from extracts obtained decades ago from the Panamanian golden frog Atelopus zeteki. Detailed NMR and mass spectral analyses have provided the structure and relative stereochemistry of zetekitoxin AB and have revealed that it is an analog of saxitoxin. The proposed structure is characterized by richness of heteroatoms (C16H25N8O12S) and contains a uni

SUBMITTER: Yotsu-Yamashita M 

PROVIDER: S-EPMC384749 | biostudies-literature | 2004 Mar

REPOSITORIES: biostudies-literature