Frog toxin

Firstly, although epiboxidine was designed to be far less toxic than the related frog toxin epibatidine, it is still sufficiently hazardous to be an unlikely catalyst. In addition, the poor catalytic activity of epibatidine, as demonstrated by Dickerson and Janda, combined with the requirement for a multistep synthesis, make epiboxidine an... 

This sequence was used for an efficient synthesis of rf/-pumiliotoxin C (2), a frog toxin, from 1. 

Synonyms Fhyllobates toxin Pitohui toxin Ifrita toxin poison dart frog toxin Chemical/Pharmaceutical/Other Class Steroidal alkaloid neurotoxin Chemical Formulas o Batrachotoxin C31H42N2O6 o Homobatrachotoxin C32H44N2O6 o Batrachotoxinin-A C24H35NO5... 

Other animals also make use of toad toxins, for example, after consumption of toads, hedgehogs spread saliva over their spines Like the toads, some frogs also secrete active substances from their skin glands. These highly poisonous toxins (see frog toxins) are mostly alkaloids, some of which have also been identified in toads. 

A synthesis of poison-dart frog toxin has been described that begins with L-glutamic acid. 

The numbered carbons in the product correspond to the same numbered carbons in L-glutamic acid. No bonds to carbon-2 are made or broken in the synthesis. If the configuration at carbon-5 in the product is R, which of the following best represents the stereochemistry of the frog toxin ... 

Animal Toxins Frog Toxins, Snake Venoms, Etc. 

Manaviazar S, Hale KJ, LeFranc A. Enantioselective formal total synthesis of the dendrobatidae frog toxin, (+)-pumilio-toxin B, via 0-directed alkyne free radical hydrostannation. Tetrahedron Lett. 2011 52 2080-2084. 

Sea urchin toxins extracted from spines or pedicellariae have a variety of pharmacological actions, including electrophysiological ones (75). Dialyzable toxins from Diadema caused a dose-dependent increase in the miniature end-plate potential frequency of frog sartorius muscle without influencing membrane potential (76). A toxin from the sea urchin Toxopneustes pUeolus causes a dose-dependent release of histamine (67). Toxic proteins from the same species also cause smooth muscle contracture in guinea pig ileum and uterus, and are cardiotoxic (77). 

Very rapid-acting paralytic neurotoxin that binds to sodium channels of nerve and muscle cells depolarizing neurons by increasing the sodium channel permeability. It is obtained from South American poison-dart frogs (Phyllobates aurotaenia, Phyllobates terribilis). It is insoluble in water but soluble in hydrocarbons and other nonpolar solvents. The dried toxin can remain active for at least a year. However, it is relatively nonpersistent in the environment. 

Aquatic frogs and toads probably need less toxin for defense than terrestrial forms. The compounds in the frogs mucus are thought to be neuroleptic, blocking dopamine receptors. They also possibly are antibacterial and aid wound repair, and they are known to elevate the level of prolactin, the amphibian Juvenile hormone (Barthalmus and Zielinski, 1988). 

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