166 



THE PLANT BASES 



[CH. 



Theobromine is 3, 7-dimethylxanthine: 



HN C=O 



I I 

 O=C C N'CHg 



\ 

 CH 



CH 3 -N C N 



It occurs in the fruit of the Cocoa plant (Theobroma Cacao), in 

 leaves of the Tea plant (Thea sinensis) and in the Kola nut (Cola 

 acuminata). 



Guanine and hypoxanthine can be represented respectively as 

 2-amino, 6-oxypurine and 6-monoxypurine: 



HN C=O HN C=O 



II II 



H 2 N C C NH HC C NH 



\ 



CH 



CH 



N C N 

 Guanine 



N C N 



Hypoxanthine 



They usually occur together and have been found in the germinating 

 seeds of the Sycamore (Acer pseudoplatanus), Pumpkin (Cucurbita 

 Pepo), Common Vetch (Vicia sativa), Meadow Clover (Trifolium 

 pratense), yellow Lupin (Lupinus luteus) and Barley (Hordeum vulgare): 

 also in the juice of the Beet (Beta). 



. 



Adenine is 6-aminopurine. It is represented as: 



= 



I=C NH 2 



I 

 HC C NH 



CH 



N C N 



It has been found in Beet (Beta), Tea leaves (Thea sinensis) and in 

 leaves of the Dutch Clover (Trifolium repens). 



Guanine, hypoxanthine and adenine are all obtained by the hydro- 

 lysis of plant nucleoproteins. 



