178 OXYPYROTARTARIC ACID. 



When treated with caustic potassa, it is resolved into 

 acetic and malic acids and alcohol. 



3. Oxypyrotartaric add, C 5 H 8 5 = C 3 H 5 (OH) 



Is formed when dicyanhydrine (p. 170) is boiled with 

 caustic potassa. Colorless crystals, easily soluble in 

 water, alcohol, and ether. Fusing point, 135. 

 The following acids are isomeric with this : 



Itamalic add, C 5 H 8 5 , is produced by heating ita- 

 monochlorpyrotartaric acid (p. 163) with water or 

 carbonates. Long, white needles. Deliquescent, easily 

 soluble in alcohol and ether. Fusing point, 60-65. 

 By heating, it is resolved into water, itaconic acid, and 

 citraconic anhydride. 



Citramalic add, C 5 H 8 5 . Citraconic acid combines 

 directly with hypochlorous acid, forming chlordtra- 

 malicacid C 5 H 7 C10 5 , a solid amorphous substance which, 

 when heated with zinc in an aqueous solution, is con 

 verted into citramalic acid. Chlorcitramalic acid is 

 also formed by the action of chlorine on citraconic 

 acid. Amorphous deliquescent mass. 



Mesamalic add, C 5 II 8 5 . Is obtained from mesamo- 

 nochlorpyrotartaric acid, like itamalic acid. Deliques 

 cent mass, that fuses at about 60. 



Glutaric add, C 5 II 8 5 . Is produced by the action of 

 nitrous acid on amidopyrotartaric acid (p. 163). 

 Syrupy mass, difficultly crystallizable. 



4. Adipomalic add, C 6 H 10 5 . From monobromadipic 

 acid by decomposing it with potassa-ley. Easily solu 

 ble, sticky, gradually crystallizing mass. 



