Suzhou Suncadia Biopharmaceuticals Co. Ltd. and Jiangsu Hengrui Medicine Co. Ltd. have synthesized isoquinolone compounds acting as phosphodiesterase PDE3A and/or PDE4 inhibitors reported to be useful for the treatment of asthma, chronic obstructive pulmonary disease (COPD), sepsis, nephritis, diabetes, allergic rhinitis, allergic conjunctivitis and rheumatic diseases.