Synthesis occurs according to the following route gamma-aminobutyric acid+acetic anhydride [forward arrow] N-acetyl-gamma amino-butyric acid + Br2 in presence of element P (red) [forward arrow] N-acetyl-alpha-bromo-gamma-aminobutyric acid + CaCO3 in aqueous solutions [forward arrow] Ca salt[long dash](HC1 hydrolysis)[forward arrow] gamma-amono-alpha-hydroxy-butyric acid (m.p. 191-192.5[degree]C).