Ethyl cyanohydroxyiminoacetate Ethyl cyanohydroxyiminoacetate Ethyl cyanohydroxyiminoacetate (oxyma) is the oxime of ethyl cyanoacetate and finds use as an additive for carbodiimides, such as dicyclohexylcarbodiimide (DCC) in peptide synthesis. It acts as a neutralizing reagent for the basicity or nucleophilicity of the DCC due to its pronounced acidity (pKa 4.60) and suppresses base catalyzed side reactions, in particular racemization. Ethyl cyanohydroxyiminoacetate is obtained in the reaction of ethyl cyanoacetate and nitrous acid (from sodium nitrite and acetic acid) in 87% yield. Because of the rapid hydrolysis of the ester, the reaction should be carried out at pH 4.5, in buffered phosphoric acid the
Ethyl nitrite Ethyl nitrite The chemical compound ethyl nitrite is an alkyl nitrite. It may be prepared from ethanol. It is used as a reagent with butanone to yield the dimethylglyoxime end product. Ethyl nitrite is the main ingredient in a traditional ethanol-based South African remedy for colds and flu known as Witdulsies and sold in pharmacies. It is known as a traditional Afrikaans remedy and may have Dutch roots, as the same remedy is apparently made by the Germano-Dutch Amish people in the USA. However FDA has blocked over-the-counter sales of this same remedy, known in the USA as "sweet nitrite"