• Journal of Photoscience
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• v.9 no.2
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• pp.178-181
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• 2002

Pyropheophorbide and pheophorbide-photosensitizers as chlorin analogues are promising new compounds for PDT because the chlorin analogues are activated with much longer red light at > 670nm and produce less long-term normal tissue phototoxicity than Photofrin. The various chlorin derivatives can be obtained by moditying peripheral substituted group among which meso-H, vinyl group and exocyclic ring are the most active positions. These characteristics prompted us to introduce various groups for constructing modified pyropheophorbide and pheophorbide a compounds. A stereospecific introduction of various double bonds at 3-position was performed to methylpheophorbide a to give a long hydrophobic moiety and cyclic derivatives. Chlorin-C$_{60}$ dyad and chlorin- $C_{60}$-porphyrin triad also were easily prepared by the reaction of terminal aldehyde of methyl pyropheophorbide a. For the reaction on meso $\delta$-position bromination and Vismeier formylation can occur. N,N-dimethylaminoacrolein also reacted on $\delta$-position and was cyclized to isobacteriochlorin, but other modification has not been succeeded. Exocyclic keto function was also modified to give purpurin derivatives, bicyclic and spiro compounds. In this presentation we report a series of modified pyropheophorbide and pheophorbide a derivatives.s.

• Bulletin of the Korean Chemical Society
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• v.2 no.4
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• pp.152-157
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• 1981

2'-(9"-Anthracenecarbonyloxy)ethyl pyropheophorbide a, methyl 3a-(9'-anthracenecarbonyloxy)pyropheophorbide a, 2'-(4"-phenylbenzoyloxy)ethyl pyropheophorbide a, and methyl 3a-(4'-phenylbenzoyloxy)pyropheophorbide a were prepared from chlorophyll a and b. Nuclear magnetic resonance study showed that the sandwich conformation is more favorable in 2'-(9"-anthracenecarbonyloxy)ethyl pyropheophorbide a than it is in other compounds.

• Bulletin of the Korean Chemical Society
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• v.32 no.9
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• pp.3473-3476
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• 2011

• Journal of Photoscience
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• v.8 no.1
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• pp.23-25
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• 2001

The methyl pheophorbide-a (MP-a) and methyl pyropheophorbide-a (MPP-a) were modified by reaction of exocyclic ketone in E-ring with nucleophilic reagent and several chlorin derivatives were synthesized. The change of the structure in E-ring served an expanding conjugation region and introduction of electron-withdrawing group, which strongly influenced the visible spectra. The Qy bands of synthesized compounds were affected by the substituents on the Qy axis(N$\sub$21/-N$\sub$23/).

• Bulletin of the Korean Chemical Society
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• v.29 no.12
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• pp.2505-2508
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• 2008