Thiol in the context of "Thioglycolate"

An odorizer is a device that adds an odorant to a gas. The most common type is one that adds a mercaptan liquid into natural gas distribution systems so that leaks can be readily detected. Other types have been used for carbon dioxide fire extinguishers.

Methanethiol (/ˌmɛθeɪnˈθaɪ.ɒl/ METH-ayn-THY-ol), also called methyl mercaptan, is an organosulfur compound with the chemical formula CH₃SH. It is a colorless flammable gas with a distinctive putrid smell. In small amounts, it is pervasive in nature and found in certain foods, such as some nuts and cheese. It contributes to many odors, including the emissions from pulp mills, bad breath, and flatus. Methanethiol is the simplest thiol and is sometimes abbreviated as MeSH.

An organic acid is an organic compound with acidic properties. The most common organic acids are the carboxylic acids, whose acidity is associated with their carboxyl group –COOH. Sulfonic acids, containing the group –SO₂OH, are relatively stronger acids. Alcohols, with –OH, can act as acids but they are usually very weak. The relative stability of the conjugate base of the acid determines its acidity. Other groups can also confer acidity, usually weakly: the thiol group –SH, the enol group, and the phenol group. In biological systems, organic compounds containing these groups are generally referred to as organic acids.

Cysteine (/ˈsɪstɪiːn/; symbol Cys or C) is a semiessential proteinogenic amino acid with the formula HS−CH₂−CH(NH₂)−COOH. The thiol side chain in cysteine enables the formation of disulfide bonds, and often participates in enzymatic reactions as a nucleophile. Cysteine is chiral, but both D and L-cysteine are found in nature. L‑Cysteine is a protein monomer in all biota, and D-cysteine acts as a signaling molecule in mammalian nervous systems. Cysteine is named after its discovery in urine, which comes from the urinary bladder or cyst, from Greek κύστις kýstis, "bladder".

The thiol is susceptible to oxidation to give the disulfide derivative cystine, which serves an important structural role in many proteins. In this case, the symbol Cyx is sometimes used. The deprotonated form can generally be described by the symbol Cym as well.

Mycothiol (MSH or AcCys-GlcN-Ins) is an unusual thiol compound found in the Actinomycetota. It is composed of a cysteine residue with an acetylated amino group linked to glucosamine, which is then linked to inositol. The oxidized, disulfide form of mycothiol (MSSM) is called mycothione, and is reduced to mycothiol by the flavoprotein mycothione reductase. Mycothiol biosynthesis and mycothiol-dependent enzymes such as mycothiol-dependent formaldehyde dehydrogenase and mycothione reductase have been proposed to be good drug targets for the development of treatments for tuberculosis.

Bacillithiol (BSH or Cys-GlcN-mal) is a thiol compound found in Bacillus species. It is likely involved in maintaining cellular redox balance and plays a role in microbial resistance to the antibiotic fosfomycin.