Guanidine and Biguanidine Derivatives of Natural Chlorins: Synthesis and Biological Assessment

Targeted molecular therapy is one of the approaches in the pharmacotherapy of cancer. The targeted action on the tumor alone does not harm the healthy tissues around the tumor and the overall patient's health, thus eliminating the adverse effects that arise upon chemotherapy or radiation treatment. The targeted delivery of drugs to specific cellular targets to increase the efficiency of drugs is an urgent goal of modern medicinal chemistry. In this work, guanidine and biguanidine groups were incorporated into chlorin e(6) aminoamide in order to create two targeting photosensitizers with high photodynamic efficiency that was proved in in vivo experiments in animals with tumors of various origins (mice Ehrlich carcinoma and rat sarcoma M-1). Optimal methods were suggested for the synthesis of the desired chlorins, which provide high reaction yields under relatively mild conditions. Taking into account the broad capabilities of guanidine and biguanidine derivatives, including heterocyclization, metal chelation, etc., the pigments suggested in this article may he considered as a platform for creating multifunctional photosensitizers of chlorin series.