Resumo: | Evaluation of the wavelength-selective cleavage of five photolabile protecting groups from two different families has been performed. Alanine, as a model bifunctional target molecule was masked at the amine terminal with o-nitrobenzyl group and at the carboxylic terminal with benzyl-type nitrogen and oxygen polyheteroaromatics, namely acridine, (thioxo)benzocoumarin and a coumarin built on the julolidine nucleus. The photosensitivity of the corresponding alanine conjugates was studied at selected wavelengths with HPLC/UV and 1H NMR monitoring. The release of the fully deprotected molecule could be achieved by sequential irradiation in variable irradiation times, which were dependent on the heteroaromatic group used.
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