1: 5-bromo-pyrimidine With iron sulphate heptahydrate; sulfuric acid in water; toluene T=-10°C; Minisci reaction; 2: C4H8O5 in water; toluene T=-10 - 0°C; Minisci reaction; 3: With sodium hydroxide in water; toluene pH=7; Cooling with ice; regioselective reaction;