THYMINE. 191 



clusters or, rarely, in short needles (GULEWITSCH l ) . It melts at about 

 321 and sublimes. It is difficultly soluble in cold water, more soluble 

 in hot water, and insoluble in alcohol. It behaves like uracil toward 

 ammonia or baryta-water and silver nitrate. Thymine is precipitated 

 by phosphotungstic acid, especially when impure. Bromine-water is 

 decolorized by thymine, producing bromthymine. For its detection 

 we make use of the sublimation, the behavior toward silver nitrate, 

 and its elementary analysis. 



In regard to the methods of preparation see KOSSEL and NEUMANN 

 and W. JoNEs. 2 



The purine and pyrimidine bodies stand in close chemical and phys- 

 iological relation to each other and for this reason the question has 

 been repeatedly raised whether the pyrimidine bases might not be formed, 

 at least in part, from the purine bases by the action of acids. Thus 

 far no conclusive investigations have been made supporting this view, 

 while on the contrary the investigations of STEUDEL 3 seem to contradict 

 such a view. 



1 Zeitschr. f. physiol. Chem., 27. 



2 Kossel and Neumann, 1. c., and W. Jones, Zeitschr. f . physiol. Chem., 29, 461. 



3 Zeitschr. f. physiol. Chem., 51 and 53 (against Burian). 



