100 



PTEROYLGLUTAMIC ACID 



has a solubility of over 15 g. per liter. It forms highly insoluble salts with 

 zinc, lead, and silver (Pfiffner et al}^). The alkali metal salts are soluble in 

 water but can be precipitated l)y the addition of alcohol. Pteroylglutamic 



Fui. 2. Crystals of i)teroylglutaniif acitl. 



acid is practically insoluble in most organic solvents but is slightly solul^le 

 in acetic acid (Pfiffner et al}^). 



The optical rotation [af^ is +16° in 0.1 N sodium hydroxide solution at 

 a concentration of 7.0 g. per liter (Weygand et alr^). 



Pteroylglutamic acid dried at moderate temperatures and at atmospheric 



" V. Weygand, A. Wiickcr, and \'. Schniicd-Kowarzik, Chnii . Ihr. 82. 2') (HMD). 



