Acetoxime, also known as acetaldoxime, is a chemical compound with the molecular formula C4H9NO. It is one of the oxime derivatives of acetone, meaning it is derived from acetone (a common organic solvent) by replacing one of its oxygen atoms with a nitrogen atom and attaching a hydrogen atom and an alkyl group (in this case, a methyl group) to the nitrogen atom.

The structure of acetoxime is as follows:
CH3-C(NOH)-CH3

Acetoxime is a colorless to pale yellow liquid with a characteristic odor. It is used in various chemical reactions and processes, including as a chemical intermediate in the synthesis of other compounds. Oximes, in general, are known for their ability to undergo reactions with carbonyl compounds (such as aldehydes and ketones) to form oxime derivatives, which can have different chemical properties and applications. These reactions are commonly used in organic chemistry and the pharmaceutical industry.