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Tlllhen mallow leaves were permitted to stand with ethanol, the ethyl 

 chlorophyllides were formed. The ethyl chlorophyllide b was less sorbed 

 than the methyl chlorophyllide b, but more sorbed than chlorophyll b. 

 With the leaf pigments, it formed a zone just below violaxanthin. The 

 ethyl chlorophyllide _a was less sorbed than the methyl chlorophyllide 

 a^, and with the leaf pigments, it formed a green zone just below the 

 yellow lutein zone, 



Isomerization of the Methyl Chlorophyllides 



The methyl chlorophyllides, prepared in mallow leaves and isolated 

 in columns of powdered sugar as described above, were dissolved in n- 

 propanol, and the solutions were heated at 100° for an hour. The pig- 

 ments in the heated solution were transferred to petroleiun ether, ad- 

 sorbed in sugar columns, and washed with petroleiim ether containing 0»5 

 per cent n-propanol. Methyl chlorophyllide b yielded a small quantity 

 of 8 green pigment that was less sorbed than the initial methyl chloro- 

 phyllide b^ and that had about the same sorbability and spectral proper- 

 ties as chlorophyl b^ itself. Methyl chlorophyllide a^ also yielded small 

 amounts of a less sorbed green pigment with spectral properties like 

 those of chlorophyll a. All these products gave positive, yellow phase 

 tests when treated with strong alkalies in methanol. 



When the heat-formed products were recovered and their solutions 

 in n-propanol were heated to 100° for an hour, the pigments were par- 

 tially (about 70-80 per cent) reconverted into the methylesters derived 

 directly from the chlorophylls. Like the isomerization of the chloro- 

 phylls, the partial reconversion or interconversion was produced almost 

 instantly by traces of alkalies added to the propanol solutions. 



