240 



Helen M. Habermann 



Infrared spectra 



Infrared absorption spectra of allagochrome and yellow pigment 

 preparations from Helianthus and Chrysanthemum strongly supported 

 the indications of NMR spectra that these are closely related com- 

 pounds. Spectra of allagochrome preparations from these two spe- 





 cies were nearly identical. A R-CH=CHC-OR' configuration is defi- 

 nitely not present in allagochrome (no band between 1715 and 1800 

 cm"-'-), although such an ester linkage joins together the caffeic 

 and quinic acid portions of the chlorogenic acid molecule. There 

 is no free NH2 group but there are several indications of bonded 



H 



n 1 



N-H of amino or amide, probably of an amide of the type R-C-N-R . 



Another phenomenon associated with the measurement of infrared 

 spectra is the observation that there is a change in spectrum of 

 allagochrome during the scanning period. Such changes were ob- 

 served with pigments prepared from both Helianthus and Chrysanthe - 

 mum leaves. It is not known whether such changes are a conse- 

 quence of the rather high intensity incandescent illumination re- 

 ceived by the samples during measurement of spectra or are merely 

 due to water in the samples. 



Elemental analyses 



The results of elemental analyses run on a lyophilized sample 

 of Helianthus allagochrome are summarized in Table II. 



Table II 

 Elemental analysis of Helianthus allagochrome 



Element Per cent 



24.36% 24.39% 



The large residue probably indicates a high salt content. We have 

 recently added passage through a mixed bed of ion exchange sepha- 

 dex as a final step in purification. The resulting samples are 

 much darker green after lyophilization (almost black) . 



