A sulfoxide's a chemical compound containing a sulfinyl functional group attached to two carbon atoms. Sulfoxides can be considered as oxidized sulfides. (The use of the alternative spelling sulphoxide's discouraged by IUPAC.) An example of a sulfoxide occurring in nature's alliin. Nature of the bond Sulfoxides are generally represented with the structural formula R-S(=O)-R', where R and R' are organic groups. The bond between the sulfur and oxygen atoms differs from the conventional double bond… (More on Sulfoxide)