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In organic chemistry, the benzoin addition is an addition reaction involving two aldehydes. The reaction generally occurs between aromatic aldehydes or glyoxals, and results in formation of an acyloin. In the classic example, benzaldehyde is converted to benzoin.
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Cycloheptatriene (CHT) is an organic compound with the formula C7H8. It is a closed ring of seven carbon atoms joined by three double bonds (as the name implies) and four single bonds. This colourless liquid has been of recurring theoretical interest in organic chemistry. It is a ligand in organometallic chemistry and a building block in organic synthesis. Cycloheptatriene is not aromatic, as reflected by the nonplanarity of the methylene bridge (-CH2-) with respect to the other atoms; however the related tropylium cation is.
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Carbazole is an aromatic heterocyclic organic compound. It has a tricyclic structure, consisting of two six-membered benzene rings fused on either side of a five-membered nitrogen-containing ring. The compound's structure is based on the indole structure, but in which a second benzene ring is fused onto the five-membered ring at the 2–3 position of indole.
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Eucaine, also known as β-eucaine or Betacaine, is a drug that was previously used as a local anesthetic. It was designed as an analog of cocaine and was one of the first synthetic chemical compounds to find general use as an anesthetic. It is a white, crystalline solid. Prior to World War I, Britain imported eucaine from Germany. During the war, a team including Jocelyn Field Thorpe and Martha Annie Whiteley developed a synthesis in Britain.
Blue flowers are rare in nature, and despite many attempts, blue roses, carnations and chrysanthemums in particular cannot not be produced by conventional breeding techniques. Blue colour in flower petals is caused by delphinidin, a type of anthocyanin, which are a class of flavonoids.
References
- ↑ Willstätter R & Everest RW (1913). "Untersuchungen über die Anthocyane. I. Über den Farbstoff der Kornblume". Justus Liebigs Ann. Chem. 401 (2): 189–232. doi:10.1002/jlac.19134010205.
- 1 2 Willstätter R, Mallison H (1915). "Untersuchungen über die Anthocyane. X. Über Variationen der Blütenfarben". Justus Liebigs Ann. Chem. 408: 147–162. doi:10.1002/jlac.19154080110.
- ↑ Shiono M, Matsugaki N, Takeda K (2005). "Structure of the blue cornflower pigment". Nature. 436 (7052): 791. Bibcode:2005Natur.436..791S. doi: 10.1038/436791a . PMID 16094358. S2CID 4312804.