ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
Regioselective reactions of methyl pyropheophorbide a with formaldehyde based on hydroxymethylation
Yang Liu, Huiqiang Wu, Xiao Zhang, Qiang Pan, Xiangmin Wang, Wei Peng, Jungang Yin, Guizhi Li, Jiazhu Li, and Jinjun Wang
Yantai University, Yantai, China
Abstract: Regioselective reactions of methyl pyropheophorbide a (MPPa) with formaldehyde based on hydroxymethylation have been studied. It was found that MPPa can react regioselectively with formaldehyde under different conditions to produce a series of 3-dioxane, 12-, 132- or 20-hydroxymethyl and 12-/132-alkenyl-substituted chlorins via Prins reaction, Blanc chloromethylation and aldol reaction, respectively. The first examples of direct C–C bond formation at 12-position of chlorophyll derivatives were also reported to give a series of 12-vinyl-substituted chlorins. These chlorins showed extend Qy absorptions and efficient singlet oxygen generation property, indicating their potential as photosensitizers for application in photodynamic therapy.
Keywords: Chlorophyll a ; Chlorin ; Prins reaction ; Blanc chloromethylation ; Aldol reaction
Full paper is available at www.springerlink.com.
Chemical Papers 72 (6) 1389–1398 (2018)