Thio-
Chemical prefix denoting the replacement of an oxygen atom with sulfur
title: "Thio-" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["chemistry-prefixes", "prefixes"] description: "Chemical prefix denoting the replacement of an oxygen atom with sulfur" topic_path: "science/chemistry" source: "https://en.wikipedia.org/wiki/Thio-" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0
::summary Chemical prefix denoting the replacement of an oxygen atom with sulfur ::
The prefix thio-, when applied to a chemical, such as an ion, means that an oxygen atom in the compound has been replaced by a sulfur atom. This term is often used in organic chemistry. For example, from the word ether, referring to an oxygen-containing compound having the general chemical structure , where R and R′ are organic functional groups and O is an oxygen atom, comes the word thioether, which refers to an analogous compound with the general structure , where S is a sulfur atom covalently bonded to two organic groups. A chemical reaction involving the replacement of oxygen to sulfur is called thionation or thiation.
Thio- can be prefixed with di- and tri- in chemical nomenclature.
The word derives (which occurs in Greek epic poetry as and may come from the same root as Latin fumus (Indo-European dh-w) and may have originally meant "fumigation substance".)
Examples
References
References
- {{JerryMarch
::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::