204 



Scientific Proceedings (114). 



venously. Apnea was usually preceded by decreased frequency 

 and depth of respiration. In dogs the effects were not constant as 

 in several cases moderate amounts of acetone produced stimulation 

 of respiration at first. As larger quantities, however, were intro- 

 duced the depressing effect became very marked. A frequent 

 phenomenon in our experiments was the occurrence of Cheyne- 

 Stokes respiration after repeated acetone injections. The greater 

 depressing effect on respiration than on circulation was also shown 

 when large amounts of acetone were injected. Blood-pressure 

 remained moderately high for some time after respiration stopped. 



Abstracts of the Communications, 

 Pacific Coast Branch. 



San Francisco, California, March p, IQ21. 



103 (1685) 



The reaction of taurin with a-naphthylisocyanate. 



By CARL L. A. SCHMIDT. 



[From the Department of Biochemistry and Pharmacology of the 

 University of California, Berkeley.] 



Although taurin differs from that particular group of amino 

 acids which constitute the building stones of the proteins in that 

 it contains a sulphonic instead of a carboxyl group, it neverthe- 

 less closely resembles the amino acids in its chemical properties. 

 Like the amino acids taurin can be quantitatively estimated when 

 in pure solution either by treating it with HNO2 and determining 

 the nitrogen set free or by titration with alkali in the presence of 

 formalin. It possesses amphoteric properties 1 and reacts with 

 many of the amino acid reagents. Thus Paal and Zitelmann 2 

 found that taurin reacts with phenylisocyanate to give a-phenyl- 

 ureidoethylsulphonic acid, Gabriel 3 and his associates prepared 



1 Winkelblech, K., Z. physik. Chem., 1901, xxxvi, 546. 



2 Paal, Cm and Zitelmann, G., Ber. d. d. chem. Gesell., 1903, xxxvi, 3337. 



3 Gabriel, S., and Heymann, P., Ber. d. d. chem. Gesell. , 1890, xxiii, 157. 

 Gabriel, S., and Colman, J., Ber. d. d. chem. Gesell, 1911, xliv, 3628. 



