Chlorophyll early research

An additional impetus for pyrrole and indole research derives from the recognition of the physiological significance of these ring systems. In the case of pyrroles the early work centered around hemin from hemoglobin and the bile pigments. The structure of chlorophyll was also shown to be pyrrole-derived. The biosynthetic connection between simple pyrroles and the macrocyclic hemin and chlorin have remained of interest up to the present (75ACR201). 

The importance of phthalocyanines, apart from their early use as models for hemes and chlorophylls, lies in the fact that metal complexes of the phthalocyanine system produce extremely intense and useful dyestuffs. Much research has therefore been devoted to physical and spectroscopic studies of these molecules (B-81MI30700). Phthalocyanines are extremely stable, are stable to light, and are insoluble in most solvents, so they are very useful dyestuffs. 

Krasnovsky AA (2002) Chlorophyll isolation, structure and function major landmarks of the early history of research in the Russian Empire and the Soviet Union. Photosynth Res 76 389 03... 

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