o-Nitrobenzyl Oxime Ethers Enable Photoinduced Cyclization Reaction to Provide Phenanthridines under Aqueous
Hidenori Okamura1,2, Momoka Iida1,2, Yui Kaneyama1,2
1Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan.
Abstract:
In this paper, we describe a novel N-O photolysis of o-nitrobenzyl oxime ethers that enables the synthesis of phenanthridines via intramolecular cyclization reactions. Without the use of additional photocatalysts or photosensitizers, the process proceeds with an efficiency of ≤96% upon exposure of the sample to near-visible light (405 nm) under aqueous conditions. Through the photoinduced production of a fluorescent phenanthridine derivative in HeLa cells, the progress of the reaction under biological conditions was demonstrated. This photoinduced cyclization reaction could be used as a different photochemical instrument to control biological processes by inducing the production of bioactive molecules.
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