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Syntheses and cellular investigations of di-aspartate and aspartate-lysine chlorin e(6) conjugates.

ABSTRACT: Chlorin e6 is a tricarboxylic acid degradation product of chlorophyll a. Four chlorin e6 bis(amino acid) conjugates were regioselectively synthesized bearing two aspartate conjugates in the 13(1),17(3)- and 15(2),17(3)-positions, or at the 13(1),15(2)via an ethylene diamine linker. One additional conjugate bearing two different amino acids, lysine at 13(1)via an ethylene diamine linker and an aspartate at 15(2)via a ?-alanine linker was also synthesized. The cytotoxicity and uptake of four di(amino acid) chlorin e6 conjugates were investigated in human HEp2 cells, and compared with chlorin e6. The most cytotoxic and most taken up conjugates were the zwitterionic 13(1),15(2)-disubstituted conjugates 28 and 33; these also localized in multiple organelles. In contrast, the anionic 13(1),17(3)- and 15(2),17(3)-di-aspartyl chlorin e6 conjugates 12 and 13 showed low dark cytoxicity and lower phototoxicity compared with chlorin e6.

SUBMITTER: Jinadasa RG

PROVIDER: S-EPMC4701634 | biostudies-literature | 2016 Jan

REPOSITORIES: biostudies-literature

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Syntheses and cellular investigations of di-aspartate and aspartate-lysine chlorin e(6) conjugates.

Jinadasa R G Waruna RG Zhou Zehua Z Vicente M Graça H MG Smith Kevin M KM

Organic & biomolecular chemistry 20151203 3

Chlorin e6 is a tricarboxylic acid degradation product of chlorophyll a. Four chlorin e6 bis(amino acid) conjugates were regioselectively synthesized bearing two aspartate conjugates in the 13(1),17(3)- and 15(2),17(3)-positions, or at the 13(1),15(2)via an ethylene diamine linker. One additional conjugate bearing two different amino acids, lysine at 13(1)via an ethylene diamine linker and an aspartate at 15(2)via a β-alanine linker was also synthesized. The cytotoxicity and uptake of four di(am ...[more]

PMID: 26633562

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Dataset Information

Syntheses and cellular investigations of di-aspartate and aspartate-lysine chlorin e(6) conjugates.

Publications

Syntheses and cellular investigations of di-aspartate and aspartate-lysine chlorin e(6) conjugates.

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