Erythromycin reacted with propionic acid under room temperature,then with propionic acid N-acetyl-L-cysteine to be salt under room temperature,finally get the erythromycin stinoprat.

• 以红霉素为起始原料,室温下与丙酸酐反应,然后与N-乙酰-L-半胱氨酸成盐,得到司丙红霉素。