Thiol

Def. also known as Mercaptan , it is an organic compound consisting of a sulfur-hydrogen group and an alkyl group.Known as the sulfur analog of alcohol.

Examples:
1) Methanethiol, A thiol existing in certain food such as cheese and nuts. It also occurs
naturally in the body, especially in the blood and the brain. It is also in animals and plant tissue.

2) L-Cysteine (Amino acid cysteine), a thiol present in food supplements, acts as an antioxidant.