FIELD: medicine, pharmaceutics.SUBSTANCE: invention refers to tetrahydroimidazo[1,5-a]pyrazine derivatives of formula I or to their pharmaceutically acceptable salts (I), wherein: Ar represents phenyl, wherein phenyl is additionally substituted by 1-3 substitutes independently specified in halogen R1 represents trifluoromethyl R2 is specified in a group consisting of hydrohyl, alkyl having 1 to 4 carbon atoms, alkoxyl having having 1 to 4 carbon atoms, cycloalkyl representing a 5-6-member monocyclic ring group consisting of carbon completely, and -NR4R5, wherein each alkoxyl is optionally substituted by one group specified in a group consisting of phenyl and -OC(O)OR8 R3 is specified in a group consisting of a hydrogen atom and alkyl having 1 to 4 carbon atoms each of R4 and R5 is independently specified is a group consisting of a hydrogen atom, alkyl having 1 to 4 carbon atoms, cycloalkyl representing a 3-8-member monocyclic ring group consisting of carbon completely, phenyl and pyridinyl, wherein each alkyl or phenyl is optionally substituted by one or more group specified in a group consisting of halogen, a cyano group, -SO2R7, -NR4R5 and -C(=O)OCH3 or R4 and R5 together with an atom, whereto attached form a 5-6-member heterocycle wherein the 5-6-member heterocycle optionally contains one or more N, O or S atom, and each 5-6-member heterocycle is optionally substituted by one or more groups consisting of halogen, hydroxyl, an amino group, alkyl having 1 to 4 carbon atoms, hydroxyalkyl 1 to 4 carbon atoms, -SO2R7, -C(O)NR4R5, -C(O)R7, =O R7 represents alkyl 1 to 4 carbon atoms and R8 is specified in a group consisting of alkyl 1 to 4 carbon atoms, and cycloalkyl representing a 5-6-member monocyclic ring group consisting of carbon completely. The invention also refers to methods for preparing them, a pharmaceutical composition having dipeptidyl peptidase IV inhibitory activity and containing said derivatives.EFFECT: there are produced new compounds and composition
