Efficient Preparation of Photolabile Agent MNI-glu by Regioselective Nitration of 4-Methoxyindoline Derivative

The present work investigates the nitration of 4-methoxy indoline derivative with different reagents and optimized conditions. We now report a simple methodology for nitration employing claycop in the presence of amine, which offers significant improvement with regard to the yield and regioselectivity, and a much more favorable isomeric ratio of products was obtained under mild conditions. Therefore, a useful method for preparation of a photolabile L-glutamate derivative was concurrently established.