A PROPOSED STRUCTURE FOR CHLOROPHYLL d

Abstract

Treatment of chlorophyll a or methyl chlorophyllide a with potassium permanganate effected oxidation of the 2-vinyl group without concomitant oxidation of the cyclopentanone ring. One of the products obtained was of especial interest because its visible absorption spectrum was identical with that of a previously known, but chemically uncharacterized, pigment—chlorophyll d. The preparation and identification of this oxidation product as 2-desvinyl-2-formyl-chlorophyll-a is given and its probable identity with chlorophyll d is discussed in detail.