The Flavin–Tryptophan Dyad F10T as a Cryptochrome Model Compound: Synthesis and Photochemistry. Issue 1 (22nd November 2016)

• Record Type: Journal Article
• Authors: Paul, Shubhajit; Meng, Lingqiang; Berger, Stefan; Grampp, Günter; Matysik, Jörg; Wang, Xiaojie
• Is Part Of: ChemPhotoChem. Volume 1:Issue 1(2017)
• Page Start: 12
• Page End: 16
• Publication Date: 2016-11-22
• Subjects: cryptochrome -- electron transfer -- photo-CIDNP NMR -- radical pair -- supramolecules; Photochemistry -- Periodicals; Periodicals; Electronic journals; 541.35
• DOI: 10.1002/cptc.201600025
• Languages: English
• ISSNs: 2367-0932

Abstract

Abstract: Many animals sense the Earth's magnetic field and use it for navigation. It has been proposed that a light‐dependent quantum effect in cryptochrome photoreceptor proteins residing in the retina allow for such an iron‐free spin‐chemical compass. The primary photochemistry in cryptochromes and photolyases is assumed to be confined mainly in a flavin adenine dinucleotide (FAD) residue and three nearby tryptophan residues. Functional studies require model compounds allowing for direct structural modifications. Inspired by the structure of natural cryptochrome, a flavin–tryptophan dyad (F10T) has been synthesized. 1 H photochemically induced dynamic nuclear polarization (photo‐CIDNP) NMR studies on F10T demonstrate the spin‐correlated radical‐pair formation through photoinduced electron transfer from donor (tryptophan) to acceptor (flavin) moieties under illumination with a white light source similar to sunlight. This is the first model compound of natural cryptochromes with a provision for controlled structural modifications. Abstract : Model behaviour : Details of the synthesis of the first flavin–tryptophan dyad (F10T) are presented. The photochemistry of F10T is investigated by means of photochemically induced dynamic nuclear polarization (photo‐CIDNP) NMR studies. F10T is demonstrated to be a reliable model compound for natural cryptochrome and has the potential for further structural modification. SCRP=spin‐correlated radical pair; D=donor; A=acceptor.