67 



group placrd l)y a N-atom. l^yridinc acts as a base^ 

 lorniing salts with acids. It is a colorless liquid of 

 great stability, being unattacked by boiling nitric acid, 

 or cbroniic acid. Pyridine may be reduced to i)ij)eri- 

 dine, and piperidine may be oxidized to pyridines 

 Piperidine, CHo ^^ present in pepper 



CHo CH2 

 \ / 



m 



in combination as piperine. Piperidine is a color- 

 less liquid witli characteristic odor, and strong basic 

 properties. 



Quinoline, GHtN, is a colorless liquid with ])eculiar 

 odor. It yields salts with acids, acting like a tertiary 

 base. It is considered to carry a benzene and a pyri- 

 dine nucleus. 



Nucleic acid is a complex substance. Yeast nucleic 

 acid has been given the formula C36H™Ni5P4032. It j^ields 

 on hydrolysis, guanosine, CioH^NsOs; adenosine, 

 CoiHx.N.04; cytidine, CHiaNaO..; and uridine, C»H:=N.O". 



Vanillin, CHO . is considered to be a hydroxal- 



/ 



CgHj-OCHg 



deliyde. It is the aromatic principle ot vanilla, and 

 is found in a number of different kinds of plants. 

 Cumarin has the following composition:}! .C •C/»H^ 



II y 



H.C.CO 

 It is the aromatic principle of woodruff (Asperula 

 odorate). It is soluble in hot water, ether and alcohol. 



Pyrogallol is a trihydric phenol to which has been 

 given the formula CH.(0H)3. In alkaline solutions 

 it is a strong reducing agent. 



Salicylic aldehyde occurs in oil of spirca; its formula 



