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Combinatorial discovery of two-photon photoremovable protecting groups.

ABSTRACT: A design principle for a two-photon photochemically removable protecting group based on sequential one-photon processes has been established. The expected performance of such groups in spatially directed photoactivation/photodeprotection has been shown by a kinetic analysis. One particular molecular class fitting into this design, the nitrobenzyl ethers of o-hydroxycinnamates, has been presented. An initial demonstration of two-photon deprotection of one such group prompted further optimization with respect to photochemical deprotection rate. This was accomplished by the preparation and screening of a 135-member indexed combinatorial library. Optimum performance for lambda >350 nm deprotection in organic solvent was found with 4,5-dialkoxy and -cyano substitution in the nitrobenzyl group and 4-methoxy substitution in the cinnamate.

SUBMITTER: Pirrung MC

PROVIDER: S-EPMC240653 | biostudies-literature | 2003 Oct

REPOSITORIES: biostudies-literature

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Combinatorial discovery of two-photon photoremovable protecting groups.

Pirrung Michael C MC Pieper Wolfgang H WH Kaliappan Krishna P KP Dhananjeyan Mugunthu R MR

Proceedings of the National Academy of Sciences of the United States of America 20031013 22

A design principle for a two-photon photochemically removable protecting group based on sequential one-photon processes has been established. The expected performance of such groups in spatially directed photoactivation/photodeprotection has been shown by a kinetic analysis. One particular molecular class fitting into this design, the nitrobenzyl ethers of o-hydroxycinnamates, has been presented. An initial demonstration of two-photon deprotection of one such group prompted further optimization ...[more]

PMID: 14557545

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