ABSTRACT
Objective To optimize the synthesis of photosensitizer chlorine e6‐C15 monomethyl ester (1) .Methods Tar‐get compound 1 was synthesized through E ring cracking of pheophorbide a (3) in methanol solution of potassium hydroxide followed by adding H2 O for ester hydrolysis with“one‐pot” process .Four main factors that influencing the synthetic yield of target compound 1 are ring cleavage reaction time (A) ,reflux hydrolysis reaction time (B) ,alkali concentration (C) and weight ratio of material 3 to alkali (D) .Each of the four factors was chosen at three levels and evaluated by the orthogonal ex‐perimentaldesignofL9(34).Results Theoptimizationtermsofthesynthesisoftargetcompound1wereB1C2A2D1 .Theyield of compound 1 was raised from 43 .0% to 56 .5% .Conclusion The developed process has the advantages of simple operation , good safety and high reaction yield ,and is suitable for industrial production .