Effects of Fatty Acids on Vitamin A Esters in Isopropanol Solutions**Received August 21, 1959, from the College of Pharmacy, Ohio State University, Columbus 10.

Vitamin A ester degradation was studied in isopropyl alcohol, isopropyl alcohol and water, cyclohexane, and in these solvents containing members of the acetic acid series of fatty acids. The results indicate that ( a ) the principal methods of degradation are oxidation and elimination in hydroxylated solvents, ( b ) water increases the rates of elimination, ( c ) fatty acids decrease the rates of elimination, and ( d ) oxidation is the main route of decomposition in hydrocarbon solvents. The stabilizing mechanism of the fatty acids was studied by examining the effects of fatty acids, water, and isopropyl alcohol on anhydrovitamin A.