Thiols are among the odorous principles in the scent of skunks and of freshly chopped onions; their presence in petroleum and natural gas is objectionable because they have disagreeable odours, interfere with catalysts used in refining processes, and produce sulfur dioxide upon combustion.
mercaptan: an old term, now disfavoured for the organic sulfur compound thiol. The word was derived from mercurium captans („seiging mercury“), which referred to the formation of characteristic crystalline mercury salts by the interaction of thiols with mercuric oxide.
