氰化叶绿素类二氢卟吩衍生物的合成及其光动力活性的研究

Synthesis of Cyanided Chlorophyllous Chlorin Derivatives and Study on Their Photodynamic Activities

以焦脱镁叶绿酸-a甲酯为起始原料,选择硝酸铊和空气为氧化剂对其进行氧化,分别在二氢卟吩周环上的3,12和15位上引进了甲酰基和甲酰甲基,与盐酸羟胺肟化后,在N,N-二甲基甲酰胺和三氯三嗪的促进下脱水并顺利地转化为氰基;利用丙二腈与二氢卟吩环上羰基的瑙文格尔反应建立了二氰亚甲基结构,进一步的结构修饰则在色基上完成了多氰基取代.通过叶绿素降解产物周环上的不同位置实施氰基化,合成了一系列未见报道的氰基取代的叶绿素类二氢卟吩衍生物,其化学结构均经UV、IR、^1H NMR及元素分析予以证实;同时也讨论了叶绿素类二氢卟吩氰基化的反应机理,并对部分新化合物的体外光动力活性进行了测试.

Pyropheophorbide-a methyl ester was used as a starting material, and its oxygenations were carried out by thaillum nitrate and air as oxidizing agent to introduce the formyl group and the formylmethyl group at 3-, 12- or 15-postion of chlorin periphery, respectively. After oximation these aldehyde groups were converted into cyano group under the reaction mediated from N,N-dimethylformamide and 2,4,6-trichloro-1,3,5-triazine. Dicyanomethylene moiety was established by Knoevenagel reaction of malononitrile with formyl group and 131-carbounyl group on the exocyclic ring. Mulcyano-substitutions on the chromophore were accomplished by further structure modifications. A series of unreported chlorins related to chlorophyll substituted with cyano-group were synthesized making use of cyanation at different positions on the periphery of chlorophyll degradation products. Their chemical structures were characterized by elemental analysis, UV, IR and ~1H NMR spectra. The reaction mechanisms on the cyanation for the chlorophyllous chlorins were discussed and in vitro photodynamic activities of some new compounds were determined.