188 Bitancourt, Nogueira, and Schivarz 



IPA, lAAL, lAA, N-HIAA, IGCA, lA, SK, and IN. This decomposi- 

 tion is accelerated by heating and exposure to visible light and occurs 

 in a matter of minutes with ultraviolet radiation. Results compa- 

 rable to this radiation are obtained with minute quantities of an oxi- 

 dant like ferric chloride. 



Salkowski and Ehrlich Reacting Spots 



In general only a small proportion of the spots and zones detected 

 in our chromatograms and ionograms gave colored reactions with 

 these reagents. IPA and lAA gave six spots, IGXA gave two, and 

 TRPH and IGCA one each, besides their own spots. Three out of 

 the six spots of IPA turned red with the application of N HCl which 

 shows that the color reaction with Salkowski and Ehrlich's reagents is 

 mostly due to the acid they contain. The same occmred with six 

 spots of lAA and one of IGCA. A number of spots gave yellow or 

 orange reactions with Ehrlich's reagent, in contrast wuth the purple or 

 pink reactions of most of the indole derivatives. 



Fluorescent and Ultraviolet Absorbing Spots 



In contrast to the color reagents, ultraviolet light revealed many 

 spots in our chromatograms and ionograms. Most of these spots are 

 fluorescent and revealed by long-wave (366 m/^) ultraviolet light. Un- 

 like many of their products of decomposition, only a few indole 

 derivatives are fluorescent but they become so on chromatograms 

 under several influences (aging, heating, ultraviolet radiation, alka- 

 linization, application of oxidants). Nonfluorescent indole deriva- 

 tives are usually short-wave ultraviolet-light absorbing stibstances 

 and quench the blue fluorescence of the filter paper induced by that 

 light. Most of the fluorescent spots and zones of our chromatograms 

 and ionograms do not give any of the reactions of the preceding sec- 

 tion. 



Dinitrophenylhydrazine Reacting Spots 



One spot or zone in the case of IGXA and lA and two in that of 

 IPA, besides their own spots, gave a brown reaction with the car- 

 bonyl reagent DHPH. TRPH and IGCA gave one spot each and 

 lAA two (zones a and d, Figure 4). In the latter case, however, zone 

 a showed a weaker reaction after ultraviolet exposure and zone d an 

 increased reaction, showing that, as a result of exposure, the sub- 

 stance of a was partially destroyed while that of zone d was trans- 

 formed into a DNPH-reacting substance. 



Volatile Substances 



The sublimation test was positive in the case of SK and IN, as 

 expected, and also in that of lAA and lAAL decomposed b) ultra- 

 violet radiation on (he j:)apcr. 



