Artemisinin, one of the topics of the Nobel Prizes in Medicine in 2015, and its derivatives have been used to treat malaria. A new study published in the Journal of Natural Products finds that the endoperoxide formation of artemisinin from dihydroartemisinic acid, its biosynthetic precursor, undergoes a mixed mechanism. The study, from the lab of Francis Yoshimoto at UTSA, used regioselectively deuterated dihydroartemisinic acid isotopologues to measure competitive intermolecular kinetic isotope effects in the formation of artemisinin. The supporting information file is over 500 pages!
Archive for the ‘Isotope effects’ Category
Mechanistic insights towards endoperoxide formation of artemisinin
Posted by naturalproductman on June 17, 2021
Posted in Antimalarial, Cyclic Peroxides, Diseases, Isotope effects, Malaria, Mass Spectrometry, Mechanistic, Peroxides, Terpenes | Leave a Comment »
The enamine is formed through an oxazolidinone intermediate
Posted by naturalproductman on February 4, 2016
When I think of organocatalysis, I usually think of a carbonyl compound forming an enamine intermediate, which in turn attacks an electrophile. The enamine is usually formed when the carbonyl compound reacts with a proline-derived catalyst. By using Gaussian and experimental KIE calculations, Matthew Vetticatt and co-workers at Binghamton University reported in JACS on the way that the enamine compound is formed: through an oxazolidinone intermediate.
A review article on determining the transition state structures based on KIEs.
Posted in Computational, Isotope effects, Mechanistic | Leave a Comment »
Syn-elimination
Posted by naturalproductman on May 14, 2014
Cristina de Meo and co-workers from Southern Illinois University reported in Organic Letters on a thiosialoside elimination of a thiophenol group, occuring by syn-elimination.
Posted in Half-chair, Isotope effects, Mechanistic | 1 Comment »
Half chair transition state
Posted by naturalproductman on February 17, 2012
Andrew Bennet and co-workers from Simon Fraser University have reported in JACS on a transition state study of a sialidase enzyme.
Posted in Enzymes, Glucoside, Isotope effects, Mechanistic, Methodology, Proteins | Leave a Comment »