STRUCTURE OF METHYLPHEOPHORBIDE‐RCI*

Abstract

Abstract— The methanolic extract of the cyanobacterium (blue‐green alga) Spirulina geitleri has been treated with methanolic acid to convert all chlorophyllous pigments to their methylpheophorbides. Fractionation of the latter from methylpheophorbide a by thin layer chromatography and high pressure liquid chromatography yielded methylpheophorbide‐RCI. Its structure has been determined as 13 2 S‐hydroxy‐20‐chloro‐methylpheophorbide a by 1 H‐nuclear magnetic resonance, absorption and circular dichroism spectroscopy, mass spectrometry and by partial synthesis from chlorophyll a . The pigment is isolated from Spirulina geitleri irrespective of the use or omission of chlorinated substances during the isolation procedure.