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Updated: Sep 20, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Enantiodifferentiating Z-E photoisomerization of cyclooctene sensitized by DNA and RNA
1Department of Molecular Chemistry, Faculty of Engineering, Osaka University, 2-1, Yamada-oka, Suita 565-0871, Japan.
Abstract:
DNA and RNA have been shown for the first time to function as chiral photosensitizers in aqueous solution, to effect the enantiodifferentiating photoisomerization of (Z)-cyclooctene (1Z), giving the chiral (E)-isomer in enantiomeric excesses (ee's) of up to 15%. In order to elucidate the effect of nucleotide sequence, enantiodifferentiating photoisomerization of 1Z was also performed using oligo and homopolynucleotides as chiral sensitizer. The -18.8% ee was observed by using d(T)15.d(A)15 as sensitizer, whereas sensitization by the poly(U).poly(A) duplex gave only racemic (E)-cyclooctene. From these results, oligothymidine sequence is essential for efficient enantioselective photoisomerization of 1Z.
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