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In the Staedel–Rugheimer pyrazine synthesis (1876), 2-chloroacetophenone is reacted with ammonia to the amino ketone, then condensed and then oxidized to a pyrazine. [5] A variation is the Gutknecht pyrazine synthesis (1879) also based on this selfcondensation , but differing in the way the alpha-ketoamine is synthesised.
Chemically, acetylpyrazine is a pyrazine and a ketone. [2] Natural occurrence. Acetylpyrazine is found in foods such as seeds, nuts and meats. ... Synthesis Note that ...
Pyridazines are rare in nature, possibly reflecting the scarcity of naturally occurring hydrazines, common building blocks for the synthesis of these heterocycles.The pyridazine structure is a popular pharmacophore which is found within a number of herbicides such as credazine, pyridafol and pyridate.
Pyrimidine (C 4 H 4 N 2; / p ɪ ˈ r ɪ. m ɪ ˌ d iː n, p aɪ ˈ r ɪ. m ɪ ˌ d iː n /) is an aromatic, heterocyclic, organic compound similar to pyridine (C 5 H 5 N). [3] One of the three diazines (six-membered heterocyclics with two nitrogen atoms in the ring), it has nitrogen atoms at positions 1 and 3 in the ring.
Leopold Rügheimer (May 5, 1850 – May 24, 1917) was a notable German chemist whose name is connected to the Staedel-Rugheimer pyrazine synthesis, a reaction that was discovered by himself and Wilhelm Staedel. Rügheimer was born in Walldorf (near Meiningen) in 1850 as the son of a merchant.
The diazinanes have six-membered cyclohexane-like ring but with two carbon atoms replaced by nitrogen atoms.The three isomers of triazinane are distinguished by the positions of their nitrogen atoms, and are referred to as 1,2-diazinane, 1,3-diazinane, and 1,4-diazinane (more commonly called piperazine).
This page was last edited on 14 March 2008, at 19:55 (UTC).; Text is available under the Creative Commons Attribution-ShareAlike 4.0 License; additional terms may ...
The current hypothesis is that pyrazinoic acid blocks synthesis of coenzyme A. Pyrazinoic acid binds weakly to the aspartate decarboxylase PanD, triggering its degradation. [23] This is an unusual mechanism of action in that pyrazinamide does not directly block the action of its target, but indirectly triggers its destruction. [citation needed]