Quinoxalines, also called benzopyrazines, in organic chemistry, are heterocyclic compounds containing a ring complex made up of a benzene ring and a pyrazine ring (formula I); they are isomeric with the cinnolenes, phthalazines and quinazolines. They are formed by the condensing ortho-diamines with 1.2 diketone, the parent substance of the group, quinoxaline, resulting when glyoxal is so condensed, whilst substitution derivatives arise when a-ketonic acids, a-chlorketones, a-aldehyde alcohols and a-ketone alcohols are used in place of diketones. Organic chemistry is the scientific study of the structure, properties, composition, reactions, and synthesis of organic compounds that by definition contain carbon. ... Heterocyclic compounds are substances which contain a ring structure as found in benzene and the aromatic compounds, or aromatic hydrocarbons, but in which other atoms than carbon, such as sulfur, oxygen or nitrogen are found as part of the ring. ... Benzene, C6H6, PhH, or benzol is a colorless and flammable liquid with a pleasant, sweet smell. ... Pyrazine is a heterocyclic aromatic organic compound. ... In chemistry, isomers are molecules with the same chemical formula and often with the same kinds of bonds between atoms, but in which the atoms are arranged differently. ... Quinazoline is a compound made up of two fused six-membered simple aromatic rings. ... Ammonia Amines are organic compounds containing nitrogen as the key atom in the amine functional group. ... A ketone is either the functional group characterized by a carbonyl group linked to two other carbon atoms or a compound that contains this functional group. ... An acid (often represented by the generic formula AH) is typically a water-soluble, sour-tasting chemical compound. ... An aldehyde is either a functional group consisting of a terminal carbonyl group, or a compound containing a terminal carbonyl group. ... In general usage, alcohol (from Arabic al-ghawl الغول) refers almost always to ethanol, also known as grain alcohol, and often to any beverage that contains ethanol (see alcoholic beverage). ...

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