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Independent Photochemical Generation and Reactivity of Nitrogen-Centered Purine Nucleoside Radicals from Hydrazines.

ABSTRACT: Photochemical precursors that produce dA• and dG(N2-H)• are needed to investigate their reactivity. The synthesis of two 1,1-diphenylhydrazines (1, 2) and their use as photochemical sources of dA• and dG(N2-H)• is presented. Trapping studies indicate production of these radicals with good fidelity, and 1 was incorporated into an oligonucleotide via solid-phase synthesis. Cyclic voltammetric studies show that reduction potentials of 1 and 2 are lower than those of widely used "hole sinks", e.g., 8-oxodGuo and 7-deazadGuo, to investigate DNA-hole transfer processes. These molecules could be useful (a) as sources of dA• and dG(N2-H)• at specific sites in oligonucleotides and (b) as "hole sinks" for the study of DNA-hole transfer processes.

SUBMITTER: Zheng L

PROVIDER: S-EPMC5711525 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

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Independent Photochemical Generation and Reactivity of Nitrogen-Centered Purine Nucleoside Radicals from Hydrazines.

Zheng Liwei L Lin Lu L Qu Ke K Adhikary Amitava A Sevilla Michael D MD Greenberg Marc M MM

Organic letters 20171110 23

Photochemical precursors that produce dA• and dG(N2-H)• are needed to investigate their reactivity. The synthesis of two 1,1-diphenylhydrazines (1, 2) and their use as photochemical sources of dA• and dG(N2-H)• is presented. Trapping studies indicate production of these radicals with good fidelity, and 1 was incorporated into an oligonucleotide via solid-phase synthesis. Cyclic voltammetric studies show that reduction potentials o ...[more]

PMID: 29125775

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