SYNTHESIS AND EVALUATION OF PHOTOLABILE SULFONAMIDES AS POTENTIAL REAGENTS FOR RAPID PHOTORELEASE OF NEUROACTIVE AMINES

The synthesis is described of photolabile sulfonamide derivatives of a mino acids, most of which incorporate a monophosphate ester to promote water solubility. Points of particular synthetic interest include obs ervations on the reduction of diaryl ketones and diarylmethanols, e.g. compounds 7 and 9, with NaBH4-TFA, and a convenient, effective sequen ce for conversion of bromoarenes into arenesulfonyl halides, e.g. 10 - -> 13. Photolysis of the glycine derivative 18a in aqueous solution re leased free glycine in poor yield, except in the presence of a very la rge excess of ascorbate as a reducing agent, The likely cause is discu ssed in terms of a decarboxylation side-reaction occurring during the overall progress of the photocleavage.