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|Section3= }} Phantasmidine is a toxic substance derived from the Ecuadorian poisonous frog Anthony's poison arrow frog (''Epipeptobates Anthonyi''), more commonly known as the “phantasmal poison frog”. It is a nicotinic agonist, meaning it binds to nicotinic receptors in the body and mimics the effects of the neurotransmitter acetylcholine. This causes the stimulation of the body’s parasympathetic nervous system, which induces many inhibitory behaviors in the body such as decreased heart rate. Phantasmidine is characterized in the same class as epibatidine, which is a similar nicotinic acetylcholine agonist derived from a poisonous frog species. Some synthetic processes can even generate phantasmidine from using epibatidine as a starting reagent. Epibatidine and epibatidine-related compounds have an LD50 of around 4 µg in mice; however, the exact LD50 of phantasmidine is not known. ==Synthesis== Multiple syntheses of phantasmidine have been proposed, some of which have been included below. The general mechanism for the synthesis of phantasmidine is shown below. In the general reaction mechanism, 1,2-bis(trimethylsilyloxy)cyclobutene is reacted with the intermediate to form the second product in 85% yield. This is then run under basic conditions to produce an intramolecular aldol reaction followed by an intramolecular nucleophilic aromatic substitution, leading to the lactam product in 46% yield. The final step involves reacting this product with BH3 in THF, then reacting the product with piperazine in MeOH at reflux. 6-chloro-2-fluoro-3-pyridineacetamide is used as an intermediate in most syntheses, which is then reacted through these three general steps to produce phantasmidine. The structure of this intermediate is shown as the starting reagent in the general reaction mechanism above. Modern synthetic procedures, however, generally begin with 2-chloro-6-fluoropyridine as the starting reagent, due to its commercial availability. This is then converted in several steps to the 6-chloro-2-fluoro-3-pyridineacetamide intermediate. The overall yield of (±) phantasmidine for the modern synthesis shown below is 8% (Zhou, Q. and B. B. Snider 528). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Phantasmidine」の詳細全文を読む スポンサード リンク
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