cacodyl

chemical compound

Also known as: tetramethyl diarsine

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June 22, 2026

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Cacodyl is a radical, a term used in chemistry to describe a group of atoms that can form a compound but cannot exist independently. Specifically, cacodyl, or tetramethyldiarsine ((CH₃)₂As-As(CH₃)₂), is an organoarsenic compound known for its extremely foul smell.12

Cacodylic acid (C₂H₇AsO₂) is a toxic, crystalline compound derived from cacodyl. It is primarily used as an herbicide. Arsenic compounds, in general, can be toxic and harmful to living tissues, interfering with cellular metabolism. Exposure to arsenic can occur through ingestion or inhalation of various arsenic compounds, and it can lead to acute or chronic poisoning with a range of symptoms.13

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arsenic
Commercial production and uses
…organic compounds, as for example tetramethyl diarsine, (CH₃)₂As―As(CH₃)₂, used in preparing the common desiccant cacodylic acid. Several complex organic compounds of arsenic have been employed in the treatment of certain diseases, such as amebic dysentery, caused by microorganisms.
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…organic compounds, as for example tetramethyl diarsine, (CH₃)₂As―As(CH₃)₂, used in preparing the common desiccant cacodylic acid. Several complex organic compounds of arsenic have been employed in the treatment of certain diseases, such as amebic dysentery, caused by microorganisms.
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