Alkaloids of Neotropical Poison Frogs (Dendrobatidae)

The potential of alkaloids in drug discovery

“…The Ecuadorean rain forest frog Epipedobates tricolor yielded minute quantities of epibatidine (Daly et al, 1978), whose analgesic mechanism of action as a potent nicotinic agonist was quite distinct from that of the opiates, since it had a low affinity for opioid receptors (Spande et al, 1992;Badio et al, 1994;Daly et al, 2000). The relative simplicity of the alkaloid led to the development of a number of syntheses which confirmed the structure and also allowed the exploration of structure-activity relationships (Szántay 1995).…”

Alkaloids in Animals

“…The compo sition of the secretions have been very thoroughly studied in recent years and an astonishing array of alkaloids have been discovered. Occurrences, structure elucidations, syntheses, and biological activities of the dendrobatid alkaloids have already been reviewed in detail several times (Daly et al, 1987(Daly et al, , 1993Daly and Spande, 1986;Witkop and Gossinger, 1983;Daly, 1982;Witkop, 1971). We will here only briefly report some general information about the main classes of dendrobatid alkaloids .…”

“…The amphibian alkaloids also include a great variety of indolizidines which were originally placed in a single group, the gephyrotoxins (Daly, 1982). This group has now been split into two groups, the simple indolizidines and the pumiliotoxin-A type of alkaloids (Daly et al, 1993).…”

Amphibians—Toads, Frogs, Salamanders, and Newts (Class: Amphibia)

“…40 The latter substances are cyclic nitrogen -containing compounds that include water -soluble alkaloids (tetrodotoxins), lipophilic alkaloids, and alkaloids derived from biogenic amines. 41 Some species of the family Dendrobatidae of neotropical frogs do not contain signifi cant amounts of toxins in their glandular secretions. 40 Minor classes include gephyrotoxins, 2,6 -disubstituted piperidines, pyrrolidine alkaloids, pyridylpiperidines (nor-anabasamine), indole alkaloids (frog calycanthine, frog chimonanthine), azatricyclododecenes, and amidine alkaloids.…”