Editing Aconitine (section)

==Structure and reactivity==
Biologically active isolates from ''[[Aconitum]]'' and ''[[Delphinium]]'' plants are classified as [[norditerpenoid]] [[alkaloid]]s,<ref>Biogenetically, aconitine is not a 'true' alkaloid, as it is not ultimately derived from amino acids.  Aconitine is ultimately derived from [[isoprene]], so it is technically a terpenoid and a ''pseudoalkaloid''.</ref> which are further subdivided based on the presence or absence of the C18 carbon.<ref>{{cite journal | vauthors = Shi Y, Wilmot JT, Nordstrøm LU, Tan DS, Gin DY | title = Total synthesis, relay synthesis, and structural confirmation of the C18-norditerpenoid alkaloid neofinaconitine | journal = Journal of the American Chemical Society | volume = 135 | issue = 38 | pages = 14313–20 | date = September 2013 | pmid = 24040959 | doi = 10.1021/ja4064958 | pmc = 3883312 | bibcode = 2013JAChS.13514313S }}</ref> Aconitine is a C19-norditerpenoid, based on its presence of this C18 carbon. It is barely soluble in [[water]], but very soluble in [[organic solvents]] such as chloroform or diethyl ether.<ref>{{ cite web | url = http://www.sigmaaldrich.com/catalog/product/sigma/a8001?lang=en | title = Aconitine | publisher = Sigma Aldrich |access-date=22 July 2016 }}</ref><ref>{{ cite web | url = http://datasheets.scbt.com/sc-202441.pdf | title = Aconitine sc-202441 Material Safety Data Sheet | publisher = Santa Cruz Biotechnology }}</ref> Aconitine is also soluble in mixtures of [[ethanol|alcohol]] and water if the concentration of alcohol is high enough.

Like many other alkaloids, the basic [[nitrogen]] atom in one of the six-membered ring structure of aconitine can easily form salts and ions, giving it affinity for both [[chemical polarity|polar]] and [[lipophilicity|lipophilic]] structures (such as cell membranes and receptors) and making it possible for the molecule to pass the [[blood–brain barrier]].<ref>{{ cite book | author = Dewick PM | year = 2002 | title = Medicinal Natural Products. A Biosynthetic Approach | edition = 2nd | publisher = Wiley | isbn = 978-0-471-49640-3 }}</ref> The [[Acetoxy group|acetoxyl group]] at the c8 position can readily be replaced by a [[methoxy]] group, by heating aconitine in [[methanol]], to produce a 8-deacetyl-8-''O''-methyl derivatives.<ref>{{ cite journal |vauthors=Desai HK, Joshi BS, Ross SA, Pelletier SW | title = Methanolysis of the C-8 Acetoxyl Group in Aconitine-Type Alkaloids: A Partial Synthesis of Hokbusine A | journal = Journal of Natural Products | year = 1989 | volume = 52 | issue = 4 | pages = 720–725 | doi = 10.1021/np50064a009 | bibcode = 1989JNAtP..52..720D }}</ref> If aconitine is heated in its dry state, it undergoes a [[pyrolysis]] to form pyroaconitine ((1α,3α,6α,14α,16β)-20-ethyl-3,13-dihydroxy-1,6,16-trimethoxy-4-(methoxymethyl)-15-oxoaconitan-14-yl benzoate) with the chemical formula C<sub>32</sub>H<sub>43</sub>NO<sub>9</sub>.<ref>{{ cite book |veditors=Manske RH, Rodrigo R | chapter = Chapter 1 The Structure and Synthesis of C<sub>19</sub>-Diterpenoid Alkaloids |vauthors=Pelletier SW, Mody NV | title = The Alkaloids: Chemistry and Physiology | volume = 17 | year = 1979 | page = 4 | doi = 10.1016/S1876-0813(08)60296-1 | chapter-url = https://books.google.com/books?id=NTXlVrG0oIcC&pg=PA4 | isbn = 9780080865416 }}</ref><ref>{{ cite web | url = http://www.chemspider.com/Chemical-Structure.10211301.html | title = Pyroaconitine ChemSpider ID: 10211301 | publisher = Chemspider }}</ref>