Editing Quinine (section)

===Biosynthesis===
[[File:Quinine Biosynthesis.png|class=skin-invert-image|thumb|Quinine biosynthesis]]
In the first step of quinine [[biosynthesis]], the enzyme strictosidine synthase catalyzes a stereoselective [[Pictet–Spengler reaction]] between [[tryptamine]] and [[secologanin]] to yield [[strictosidine]].<ref>{{cite journal | vauthors = Treimer JF, Zenk MH | title = Purification and properties of strictosidine synthase, the key enzyme in indole alkaloid formation | journal = European Journal of Biochemistry | volume = 101 | issue = 1 | pages = 225–233 | date = November 1979 | pmid = 510306 | doi = 10.1111/j.1432-1033.1979.tb04235.x | doi-access = free }}</ref><ref>{{cite journal | vauthors = Mizukami H, Nordlöv H, Lee SL, Scott AI | title = Purification and properties of strictosidine synthetase (an enzyme condensing tryptamine and secologanin) from Catharanthus roseus cultured cells | journal = Biochemistry | volume = 18 | issue = 17 | pages = 3760–3763 | date = August 1979 | pmid = 476085 | doi = 10.1021/bi00584a018 }}</ref> Suitable modification of [[strictosidine]] leads to an aldehyde. Hydrolysis and decarboxylation would initially remove one carbon from the iridoid portion and produce corynantheal. Then the [[tryptamine]] side-chain were cleaved adjacent to the nitrogen, and this nitrogen was then bonded to the acetaldehyde function to yield cinchonaminal. Ring opening in the indole heterocyclic ring could generate new amine and keto functions. The new quinoline heterocycle would then be formed by combining this amine with the aldehyde produced in the [[tryptamine]] side-chain cleavage, giving cinchonidinone. For the last step, hydroxylation and methylation gives quinine.<ref>{{cite book |title=Medicinal natural products : a biosynthetic approach |publisher=Wiley |isbn=9780470742761 |pages=380–381 |edition=3rdition}}</ref><ref>{{cite journal | vauthors = O'Connor SE, Maresh JJ | title = Chemistry and biology of monoterpene indole alkaloid biosynthesis | journal = Natural Product Reports | volume = 23 | issue = 4 | pages = 532–547 | date = August 2006 | pmid = 16874388 | doi = 10.1039/b512615k }}</ref>