This research proposal involves the understanding and quantitative design of cycloadditions suitable for biomolecule labeling under physiological conditions. We will: 1. perfect computational methods to be used for accurate and routine predictions of rate constants of cycloadditions in aqueous media; 2. complete the computations of rate constants of all possible cycloadditions between cycloaddends that are known to be bioorthogonal cycloaddition reagents with a given cycloaddition partner but have not been explored in reactivities towards other cycloaddends. The resulting matrix of predicted rates for a series of dienes and 1,3-dipoles with a series of alkenes and alkynes will guide the discovery of additional useful bioorthogonal and mutually orthogonal reactions; 3. develop generalized design principles for new reagents and orthogonal reaction pairs; 4. conceive of new cycloaddition components and test them computationally in order to determine promising reactant pairs for bioorthogonal cycloadditions. 5. Compute fluorescence wavelengths and quantum yields for newly designed fluorogenic probes. The results will enhance the monitoring of biological processes and disease states.

Public Health Relevance

This research proposal involves the understanding and quantitative design of cycloadditions suitable for biomolecule labeling under physiological conditions. We will employ a variety of quantum mechanical calculations to understand what controls mutual reactions of components A and B and to assess their reactivities with components of biological systems, such as proteins, nucleic acids, and carbohydrates. We seek to understand reactions used or planned by our experimental collaborators and to predict new useful cycloaddition reactions for experimental application to the monitoring of biological processes and disease states.

National Institute of Health (NIH)
National Institute of General Medical Sciences (NIGMS)
Research Project (R01)
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Synthetic and Biological Chemistry A Study Section (SBCA)
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Lees, Robert G
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University of California Los Angeles
Schools of Arts and Sciences
Los Angeles
United States
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Shao, Zhuzhou; Liu, Wei; Tao, Huimin et al. (2018) Bioorthogonal release of sulfonamides and mutually orthogonal liberation of two drugs. Chem Commun (Camb) 54:14089-14092
Levandowski, Brian J; Gamache, Raymond F; Murphy, Jennifer M et al. (2018) Readily Accessible Ambiphilic Cyclopentadienes for Bioorthogonal Labeling. J Am Chem Soc 140:6426-6431
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Champagne, Pier Alexandre; Houk, K N (2017) Influence of Endo- and Exocyclic Heteroatoms on Stabilities and 1,3-Dipolar Cycloaddition Reactivities of Mesoionic Azomethine Ylides and Imines. J Org Chem 82:10980-10988
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