A process for preparing a compound (C) represented by the following formula: wherein R1 represents hydrogen, C1-6 alkyl or C3-8 cycloalkyl, and R2 represents hydrogen or methoxy, characterized by reacting a compound (A-1) represented by the following formula: wherein R1 has the same definition as above, with a compound (B) represented by the following formula: wherein R2 has the same definition as above, and L represents a leaving group, is provided. Compound (C) is effective for prevention or treatment of various diseases associated with angiogenesis neoplasia.