Humanwell Healthcare (Group) Co. Ltd. has synthesized dihydropyrimidoisoquinolinone derivatives acting as G protein-coupled receptor 84 (GPR84) antagonists reported to be useful for the treatment of chronic obstructive pulmonary disease (COPD), rheumatoid arthritis, inflammatory bowel disease, pulmonary fibrosis, vasculitis, infections, metabolic and endocrine disorders, among others.