CHED 499 |
| It is known that a variety of á,â-unsaturated carbonyl compounds exhibit antifungal and anti-neoplastic properties. .[i] The bioactivity of these compounds has generally been attributed to their ability to react with sulfhydryl-containing systems essential to normal metabolism. A number of studies involving the above compounds have shown that a model thiol compound such as cysteine adds to the exocyclic â carbon of the á,â-unsaturated moiety in a Michael-type addition ; compounds that exhibit this reactivity have been shown to be cytotoxic. Curcumin, (1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl)-1,6-heptadiene-3,5-dione, is a compound that exhibits á,â conjugation. It is thought that derivatives of Curcumin such as Didemethoxycurcumin will exhibit similar characteristics due to their á, â saturated conjugated systems. These similarities make Didemethoxycurcumin an interesting target to study rates of addition of different thiol nucleophiles to Didemethoxycurcumin and other Curcumin derivatives. A preliminary kinetic study of curcumin and the thiolate anion of â-mercaptoethanol indicates three observable processes.[ii] This research will serve to continue a structure-reactivity study of curcumin derivatives. The rate of reaction between the anion of â-Mercaptoethanol as the nucleophile and Didemethoxycurcumin, will be measured in 50% CH3CN 50% H2O, at 25 °C at a constant ionic strength of µ = 0.1 M KCl. Kinetic scans of the addition of â-Mercaptoethanol to the curcuminoids reveal two processes; first the formation of the enolate almost immediately upon mixing and the second the addition of â-Mercaptoethanol to the beta carbon. Future work will include the study of other nucleophiles including L-Cysteine under the same conditions. Product studies to determine the nature of the slow and fast processes will need to be conducted. |
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Undergraduate Research Poster Session: Organic Chemistry
11:00 AM-1:00 PM, Monday, March 26, 2007 Hyatt Regency Chicago -- Riverside Center, Poster
Division of Chemical Education |