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Large-scale synthesis of a persistent trityl radical for use in biomedical EPR applications and imaging.

ABSTRACT: Tetrathiatriarylmethyl radicals are ideal spin probes for biological electron paramagnetic resonance (EPR) spectroscopy and imaging. The wide application of trityl radicals as biosensors of oxygen or other biological radicals was hampered by the lack of affordable large-scale syntheses. We report the large-scale synthesis of the Finland trityl radical using an improved addition protocol of the aryl lithium monomer to methylchloroformate. A new reaction for the formal one-electron reduction of trityl alcohols to trityl radicals using neat trifluoroacetic acid is reported as well. Initial applications show that the compound is very sensitive to molecular oxygen. It has already provided high-resolution EPR images on large aqueous samples and should be suitable for a broad range of in vivo applications.

SUBMITTER: Dhimitruka I

PROVIDER: S-EPMC2714045 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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Large-scale synthesis of a persistent trityl radical for use in biomedical EPR applications and imaging.

Dhimitruka Ilirian I Velayutham Murugesan M Bobko Andrey A AA Khramtsov Valery V VV Villamena Frederick A FA Hadad Christopher M CM Zweier Jay L JL

Bioorganic & medicinal chemistry letters 20071017 24

Tetrathiatriarylmethyl radicals are ideal spin probes for biological electron paramagnetic resonance (EPR) spectroscopy and imaging. The wide application of trityl radicals as biosensors of oxygen or other biological radicals was hampered by the lack of affordable large-scale syntheses. We report the large-scale synthesis of the Finland trityl radical using an improved addition protocol of the aryl lithium monomer to methylchloroformate. A new reaction for the formal one-electron reduction of tr ...[more]

PMID: 17964156

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