It is found in the skin of poison frogs from the genera Dendrobates, Epipedobates, Minyobates, and Phyllobates[1][2] and toads from the genus Melanophryniscus.

When the toxin enters the bloodstream through cuts in the skin or by ingestion,[4] it can cause hyperactivity, convulsions, cardiac arrest and ultimately death.

The side chain conformation of substituents at the C-2’ position plays an important role in the toxicity of the compound.

One of the starting materials of the synthesis include the N-Boc derivative of L-proline methyl ester (1).

Then, a Wittig type of reaction followed by dehydration with thionyl chloride and pyridine results in alkene 2.

The lack of pumiliotoxin 251D in eggs and tadpoles confirms that the toxin is not passed over from adult frogs to their offspring.

In general, pumiliotoxins are known as positive modulators of voltage-gated sodium channels (VGSCs, membrane proteins).

Both the steady-state activation and inactivation curves of each mammalian VGSCs are shifted to a more negative potential.

The effect of pumiliotoxin 251D on the voltage-gated potassium channels (VGPCs) currents is quite small.

Pumiliotoxin is a toxin found in poison dart frogs (genus Dendrobates and Phyllobates).

[1] Symptomatic treatment of PTX 251D poisoning include reducing the convulsions using carbamazepine.