Abstract: An object of the present invention is to provide a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one, which is useful as an antitumor agent, the crystal being stable, excellent in oral absorbability, highly chemically pure, and suitable for mass production. The present invention provides a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one that exhibits an X-ray powder diffraction spectrum containing at least three characteristic peaks at diffraction angles (2?±0.2°) selected from 9.5°, 14.3°, 16.7°, 19.1°, 20.8°, 21.9°, and 25.2°. The present invention also provides a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one that exhibits an X-ray powder diffraction spectrum containing at least seven characteristic peaks at diffraction angles (2?±0.2°) selected from 13.5°, 17.9°, 19.5°, 20.

Abstract: An object of the present invention is to provide a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one, which is useful as an antitumor agent, the crystal being stable, excellent in oral absorbability, highly chemically pure, and suitable for mass production. The present invention provides a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one that exhibits an X-ray powder diffraction spectrum containing at least three characteristic peaks at diffraction angles (2?±0.2°) selected from 9.5°, 14.3°, 16.7°, 19.1°, 20.8°, 21.9°, and 25.2°. The present invention also provides a crystal of (S)-1-(3-(4-amino-3-((3,5-dimethoxyphenyl)ethynyl)-1H-pyrazolo[3,4-d]pyrimidin-1-yl)-1-pyrrolidinyl)-2-propen-1-one that exhibits an X-ray powder diffraction spectrum containing at least seven characteristic peaks at diffraction angles (2?±0.2°) selected from 13.5°, 17.9°, 19.5°, 20.

Abstract: Provided is a c-Met inhibitory antitumor agent which mitigates side effects by selectively affecting tumor cells in which c-Met is specifically expressed, having a formula (I) or its salt: wherein each of R1 and R2 are independently a hydrogen atom, an optionally substituted C1-6 alkyl, C3-10 cycloalkyl, C6-14 aromatic hydrocarbon, or saturated or unsaturated heterocyclic group, or R1 and R2 may form, together with the nitrogen atom to which they are attached, an optionally substituted nitrogen-containing heterocyclic ring; R3 is a C1-6 alkyl group; and R4, R5, and R6, are independently a hydrogen atom, a halogen atom, an optionally substituted C1-6 alkyl group, a C1-6 alkoxy group, a C1-6 alkylamino group, an optionally substituted aromatic hydrocarbon group, or an optionally substituted saturated or unsaturated heterocyclic group, or R5 and R6 may form a ring together with the phenyl ring to which they are attached.

Abstract: To provide an antitumor agent which exhibits excellent c-Met inhibitory effect and mitigates side effects by virtue of selectively affecting to tumor cells in which c-Met is specifically expressed.