CRYSTAL FORM OF THE PYRIDO[3,4-D]PYRIMIDINE DERIVATIVE Russian patent published in 2023 - IPC C07D471/04 A61K31/519 A61P9/00 A61P11/00 A61P29/00 A61P35/00 A61P43/00 

FIELD: chemistry.

SUBSTANCE: invention relates to a crystalline form of a compound having the formula (I), where R¹ represents a hydrogen atom or a C _1-3 alkyl group, R² represents a hydrogen atom or an oxo group, L represents a single bond or a C_1-3 alkylene group, and X is CH or N, namely the compound with formula (I) is 1-(6-((6-((1R)-1-hydroxyethyl)-8-(isopropylamino)pyrido[3,4-d ]pyrimidine-2-yl)amino)-3-pyridyl)piperazin-2-one, wherein THE said crystalline form of the compound has peaks with diffraction angles of 2θ = 6.3°, 6.6°, 11.6°, 16.9° and 20.0° in the spectrum of powder X-ray diffraction or 2θ = 5.3°, 7.3°, 10.3°, 15.1° and 17.4° in the spectrum of powder X-ray diffraction; where the compound with formula (I) is 1-(6-((6-((1R)-1-methoxyethyl)-8-(isopropylamino)pyrido[3,4-d]pyrimidine-2-yl)amino)-3-pyridazyl)piperazine, where the indicated crystalline form of the compound has peaks with diffraction angle of 2θ = 5.2°, 7.6°, 8.4°, 10.5°, 15.2°, 16.9°, 20.1°, 21.0°, 23.3° and 26.6° in the spectrum of powder X-ray diffraction or 2θ = 5.2°, 6.6°, 8.1°, 15.2°, 15.9°, 16.2°, 18.8°, 20.5°, 20.8° and 21.7° in the spectrum of powder X-ray diffraction; where the compound with formula (I) is (R)-N8-isopropyl-6-(1-methoxyethyl)-N2-(5-(piperazin-1-ylmethyl)pyridin-2-yl)pyrido[3,4-d] pyrimidine-2,8-diamine, where the indicated crystalline form has peaks with diffraction angles of 2θ = 4.8°, 7.6°, 8.2°, 9.7°, 15.3°, 16.6°, 19.1°, 19.8°, 22.4° and 26.2° in the powder x-ray diffraction spectrum.

EFFECT: crystalline forms of pyrido[3,4-d]pyrimidine derivative having activity against cyclin-dependent kinase 4 and/or cyclin-dependent kinase 6 (CDK4/6).

22 cl, 28 dwg, 12 ex