74 BIBLIOGRAPHY OF 



it were obtained lutidin-dicarboxylic ester and acid. Hydroisobutyl- 

 lutidindicarboxylic ester, C5 N (CH3)2 C4 Hg H^ (CO2 C2 115)2 , obtained 

 by using valeraldehyde melts at 100° The mono-ethyl salt and free 

 acid of isobutyl-lutidin dicarboxylic were obtained and also isobutyl- 

 lutidin, C5 N ( 0113)2 H2C4 Hg , a liquid boiling at 210° to 213.° 



FITTIQ, R., 1885. 



Ber. 18, 3410-3413 ; J. Chem. Soc. 50, 225. 



Constitution of Carbopyrotritartaric Acid. 



The product of the action of acetoacetic ester and succinic acid, 

 Cs Hs O5 , which is isomeric with carbopyrotritartaric acid is called 

 methronic acid and the two acids are given the following formulae : 

 Carbopyrotritartaric acid : 



CH3 — C — C— HCO2H 



li I 

 H— C CHCO2 H 



C 



o 



Methronic acid 



CH3 — C— C— HCO2H 



II I 

 CO2 H — C CH2 

 \ / 

 C 



I 



o 



When heated they both give carbon dioxid and pyrotritartaric acid : 



CH, — C— CHCO2H, 



^ II I 

 H — C CH2 

 \ / 

 C 

 II 



o 



I 



