In the late 1980s, we reported the structures of dinoflagel-late luciferin (1) and krill luciferin (2) (Scheme 1)~[1]. Recognizing their structural similarity with chlorophylls a and b (3 and 4, respectively), we speculate that dinoflagellate luciferin (1) and krill luciferin (2) are derived through an oxidative ring cleavage at the C1-C20 bond of chlorophylls with retention of the C20 carbon atom as a carboxylate at ring D. Shortly after the structures of 1 and 2 were disclosed, chlorophyll catabolites from barley and Chlorella protothecoides were isolated and characterized (5 and 6, respectively; Scheme 1)~[2 ,3]. It is evident that, unlike dinoflagellate and krill luciferins, these catabolites are formed through cleavage of the C4-C5 bond of chlorophylls with retention of the C5 carbon atom as a formyl group at ring B. chemical bond cleavages are also known on Cd- and Zn- chelates of pyropheophorbide a (Scheme 2~[4]). Interestingly, C4-C5 bond cleavage occurred for the Cd-chelate 8 to give 10, whereas C19-C20 bond cleavage occurred for Zn-chelate 7 to give 9.
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机译：在1980年代后期，我们报道了二鞭毛晚萤光素（1）和磷虾萤光素（2）的结构（方案1）〜[1]。认识到它们与叶绿素a和b（分别为3和4）的结构相似性，我们推测，鞭毛萤光素（1）和磷虾萤光素（2）是通过叶绿素C1-C20键处的氧化环裂解而保留的。 C 20碳原子为D环的羧酸根。公开1和2的结构后不久，分离并鉴定了大麦和原绿小球藻的叶绿素分解代谢物（分别为5和6;方案1）〜[2,3]。显然，与二鞭毛藻酸酯和磷虾萤光素不同，这些分解代谢产物是通过叶绿素的C4-C5键断裂，并保留C5碳原子作为环B的甲酰基而形成的。化学键断裂在Cd和Cd上也是已知的焦脱镁叶绿酸a的锌螯合物（方案2〜[4]）。有趣的是，Cd-螯合物8发生C4-C5键断裂，而Zn-螯合物7发生C19-C20键断裂9。
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