Thiolactone Explained

Thiolactones are a class of heterocyclic compounds in organic chemistry. They are analogs of the more common lactones in which an oxygen atom is replaced with a sulfur atom. The sulfur atom is within the ring system and adjacent to a carbonyl group.

Chemistry

Thiolactones can be prepared by dehydration of thiol-containing carboxylic acids. Thiolactones can be hydrolyzed back to the thiol acids under basic conditions.^[1] β-Thiolactones can be opened by reaction at the 4-position via S_N2 nucleophilic reactions.^[2]

Occurrence

Thiolactones are intermediates in the activation of some drugs.^[3]

In nature, the most common thiolactone is homocysteine thiolactone. It is produced from homocysteine. It may play a role in protein damage.^[4] The drugs citiolone and erdosteine are modified versions of homocysteine thiolactone.

Thiolactones have been found in peptides synthesized by bacteria such as Staphylococcus aureus in order to regulate their quorum-sensing system.^[5]

See also

• Lactone
• Lactam

Notes and References

1. Stevens. Charles. Tarbell. D. Stanley. The Kinetics of Basic Hydrolysis Of Some γ-Lactones and γ-Thiolactones In Aqueous Acetone. The Journal of Organic Chemistry. December 1954. 19. 12. 1996–2003. 10.1021/jo01377a017.
2. 10.1021/jo9001728 . SN2-Type Nucleophilic Opening of β-Thiolactones (Thietan-2-ones) as a Source of Thioacids for Coupling Reactions . 2009 . Crich . David . Sana . Kasinath . . 74 . 9 . 3389–3393 . 19388715.
3. 10.1177/0091270009343005 . Metabolism and Disposition of the Thienopyridine Antiplatelet Drugs Ticlopidine, Clopidogrel, and Prasugrel in Humans . 2010 . Farid . Nagy A. . Kurihara . Atsushi . Wrighton . Steven A. . The Journal of Clinical Pharmacology . 50 . 2 . 126–142 . 19948947 .
4. 10721911 . 2000 . Jakubowski . H . Homocysteine thiolactone: Metabolic origin and protein homocysteinylation in humans . 130 . 2S Suppl . 377S–381S . The Journal of Nutrition. 10.1093/jn/130.2.377S . free .
5. 2007 . Malone . C.L . Biosynthesis of Staphylococcus aureus Autoinducing Peptides by using the Synechocystis DnaB Mini-Intein . 73 . 19 . 6036–6044 . Applied and Environmental Microbiology . 10.1128/aem.00912-07 . 17693565 . 2074992. 2007ApEnM..73.6036M .