MISCELLANEOUS NITROGEN AND SULFUR COMPOUNDS 277 



Table 1. Continued 

 AMINO ACID AMINE N-METHYL DERIVATIVES 



pipecolic acid 



piperidine 



arginine H2N-(CH2)4 NHCNH2 



agmatine NH 



chromatograms so that separation and at least a partial identification can be made at 

 once. Kamienski (7) has developed a general method for determining volatile amines in 

 plants. Paper chromatography is carried out with a butanol-acetic acid-water solvent. 

 Primary amines are detected with ninhydrin, secondary amines with nitroprusside, and 

 tertiary amines with phosphomolybdic acid. Secondary and tertiary amines may also be 

 detected with iodine vapor. Tertiary amines and quaternary ammonium compounds can 

 be detected with potassium tetraiodobismuthate (Dragendorff's reagent). A preliminary 

 separation of the amines by distillation, precipitation, etc. is necessary before paper 



chromatography since the detection reagents are not specific i.e. ninhydrin reacts 



with amino acids, nitroprusside with suLEhydryl compounds, and alkaloids with Dragen- 

 dorff's reagent. Other special reagents may be applied for detection of certain amines, 

 such as diazotized sulfanilic acid (Pauli's reagent) for tyramine, histamine, etc. Blau 

 (8) has identified amines in biological materials by concentrating them on ion exchange 

 resin and then chromatographing on paper. Many other specific reactions will be found 

 in the general references. 



ISOBUTYLAMIDES 



Brief mention needs to be given to a group of isobutylamine derivatives which are 

 combined by an amide linkage with various unsaturated fatty acids. Analogous compounds 

 involving other aliphatic amines are not known to be naturally occurring, and the isobuty- 

 lamides are of particular interest because of their insecticidal properties. Several plants 

 which have been used as insecticides since ancient times owe their effectiveness to the 

 presence of isobutylamides. Pellitory (Anacyclus pyrethrum) is probably the best known 

 of these plants. Its roots yield the insecticide pellitorine which has been shown to be a 

 mixture of several different isobutylamides. The most abundant is an amide of 2, 4- 

 decadienoic acid: 



CHo 



V II 



^CHCH2NHCCH=CHCH=CH(CH2)4CH3 



CH3 



other isobutylamides of unsaturated acids (some acetylenic) from Cjo to Cig are found 

 in the same plant and also in a few others. In most cases mixtures seem to be present 

 and it is difficult to separate them, so that it is not always possible to decide which com- 

 ponent is the active ingredient of a natural isobutylamide insecticide. Characterization 

 of the isobutylamides depends on acidic hydrolysis and identification of the fatty acid and 

 isobutylamine. A discussion of these compounds may be found in a review of naturally 

 occurring insecticides by Feinstein and Jacobson (9). 



