Presentation Title

Comparison of Fluorogenic Cytidine Nucleosides: Developing a New Analogue to Test Structure and Properties

Faculty Mentor

Dr. Byron Purse

Start Date

23-11-2019 8:45 AM

End Date

23-11-2019 9:30 AM

Location

120

Session

poster 2

Type of Presentation

Poster

Subject Area

biological_agricultural_sciences

Abstract

Fluorescent nucleoside analogues are important in advancing knowledge of the genetic code, especially in DNA replication, expression, and maintenance. However differences in the fluorescent properties of these nucleoside analogues, as seen in response to base pairing and stacking, has yet to be fully examined. Originally synthesized by Matteucci and Wilhelmsson, tricyclic cytidine analogues such as 8-DEA-tC now include a family of compounds and exhibit a range of fluorescent properties.1 Fluorescent tricyclic cytidine analogues are widely used currently in DNA/RNA polymerase studies, measuring DNA–protein interactions, and FRET experiments.1 As a free nucleoside, 8-DEA-tC is nearly non-fluorescent (Φem = 0.006) and increases fluorescence up to Φem = 0.12 when based-paired with guanosine in double-stranded DNA.2 We are synthesizing a related compound, the oxo-analogue 8-DEA-tCo, to better examine the mechanism for the fluorescence turn-on since it is not yet fully understood.3 It has been demonstrated that changing the constituent atoms, such as a sulfur to an oxygen atom in this study, alters the photophysical properties of the nucleoside analogue, but in ways that are difficult to predict. The five-step synthesis of 8-DEA-tCo includes the challenging step of adding 4-diethylamino-2-aminophenol to a protected 5-bromouridine, with activation by POCl3 and 1H-triazole. The synthesis of the compound 4-diethylamino-2-aminophenol is completed in a four-step synthesis with an overall 40% yield. Once 8-DEA-tCo is synthesized, a phosphoramidite derivative of the nucleoside will be synthesized in two steps to make oligonucleotides for further testing. In addition, a comparison will be made between 8-DEA-tCo to 8-DEA-tC to better examine the photophysical properties as a free nucleoside in single-stranded and double-stranded DNA. These studies provide a greater understanding of the relationship between structural and photophysical properties of analogues and will allow for better design of highly predictable fluorescent probes in nucleic acid structure and dynamics research.

This document is currently not available here.

Share

COinS
 
Nov 23rd, 8:45 AM Nov 23rd, 9:30 AM

Comparison of Fluorogenic Cytidine Nucleosides: Developing a New Analogue to Test Structure and Properties

120

Fluorescent nucleoside analogues are important in advancing knowledge of the genetic code, especially in DNA replication, expression, and maintenance. However differences in the fluorescent properties of these nucleoside analogues, as seen in response to base pairing and stacking, has yet to be fully examined. Originally synthesized by Matteucci and Wilhelmsson, tricyclic cytidine analogues such as 8-DEA-tC now include a family of compounds and exhibit a range of fluorescent properties.1 Fluorescent tricyclic cytidine analogues are widely used currently in DNA/RNA polymerase studies, measuring DNA–protein interactions, and FRET experiments.1 As a free nucleoside, 8-DEA-tC is nearly non-fluorescent (Φem = 0.006) and increases fluorescence up to Φem = 0.12 when based-paired with guanosine in double-stranded DNA.2 We are synthesizing a related compound, the oxo-analogue 8-DEA-tCo, to better examine the mechanism for the fluorescence turn-on since it is not yet fully understood.3 It has been demonstrated that changing the constituent atoms, such as a sulfur to an oxygen atom in this study, alters the photophysical properties of the nucleoside analogue, but in ways that are difficult to predict. The five-step synthesis of 8-DEA-tCo includes the challenging step of adding 4-diethylamino-2-aminophenol to a protected 5-bromouridine, with activation by POCl3 and 1H-triazole. The synthesis of the compound 4-diethylamino-2-aminophenol is completed in a four-step synthesis with an overall 40% yield. Once 8-DEA-tCo is synthesized, a phosphoramidite derivative of the nucleoside will be synthesized in two steps to make oligonucleotides for further testing. In addition, a comparison will be made between 8-DEA-tCo to 8-DEA-tC to better examine the photophysical properties as a free nucleoside in single-stranded and double-stranded DNA. These studies provide a greater understanding of the relationship between structural and photophysical properties of analogues and will allow for better design of highly predictable fluorescent probes in nucleic acid structure and dynamics research.