ORGN 497 |
| Robert A. Horton1, Lisa A. Eidenschink2, Joshua D. Bagnato1, J. B. Alexander Ross3, and Charles B. Grissom1. (1) Department of Chemistry, University of Utah, 315 South 1400 East, Salt Lake City, UT 84112-0850, (2) Department of Chemistry, University of Washington, Box 351700, Seattle, WA 98195-1700, (3) Department of Chemistry, University of Montana, Missoula, MT 59812 |
| A series of fluorescent cobalamin analogs (CobalaFluors) were synthesized with increasing linker length between cobalamin and the fluorophore to analyze the fluorescent quenching properties of the 5’-OH α-ribofuranoside modified CobalaFluors. An increase in fluorescent quantum yield is observed with an increase in linger length from 5 to 9 atoms. However, no further increase in fluorescent efficiency is observed upon extending the linger length to 16 atoms. The flexibility of the alkane chain of the linker allows the fluorophore to fold back to cobalamin and reestablish the quenching interaction to maintain low quantum yields. Viscosity studies on the fluorescent lifetimes of the CobalaFluors exhibit a direct correlation between an increase in lifetimes and viscosity, demonstrating the ability of the fluorophore to fold back to the cobalamin to quench the excited state of the fluorophore and maintain low fluorescent efficiency. |
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Total Synthesis, Asymmetric Reactions and Syntheses, Bioorganic
9:00 AM-11:00 AM, Wednesday, March 31, 2004 Anaheim Convention Center -- Hall C, Poster
Sci-Mix
Division of Organic Chemistry |