FIELD: pharmacology.SUBSTANCE: invention relates to new compounds of the formula (I) and their pharmaceutically acceptable salts which have the properties of a catechol-O-methyltransferase (COMT) inhibitor. In the compound of the formula (I),where R1 is hydrogen, methyl, Br, F or Cl； R2 is hydrogen, lower alkyl, Br, I, C3-6cycloalkyl, C(O)O-lower alkyl, C(O)NH-lower alkyl substituted by halogen, C(O)(morpholine) or is 3,4-dihydronaphthalen-2-yl optionally substituted by lower alkyl, 1,2,3,4-tetrahydronaphthalen-2-yl, 2,3-dihydrobenzofuran-6-yl, 1-methyl-2,3-dihydro-1H-indolin-5-yl, 1-methylindolin-5-yl, tetrahydropyran-4-yl, 3,6-dihydro-2H-pyran-4-yl, 2-isopropyl-1,2,3-tetrahydroisoquinolin-5-yl, 2,3-dihydro- dimethyl[1,4]dioxin-6-yl, benzo[1,3]-dioxol-5-yl, 1,2,3,4-tetrahydroisoquinolin-7-yl optionally substituted by lower alkyl, cyclohexenyl, morpholinyl, 4-methylpiperazinyl, naphthalen-1-yl, naphtalen-2-yl, or represents (CHR)n-phenyl optionally substituted by one to five substituents R4, where R4 is F, Cl, CN, CH2-CN, lower alkyl, hydroxy, lower alkyl, substituted hydroxy, lower alkoxy, (CH2)1.2-lower alkoxy, S-lower alkyl, (CH2)1.2-S-lower alkyl, -CH2)1.2-S (O)2-lower alkyl, -S(O)2-lower alkyl, -S(O)2-di-lower alkylamino, -S(O)2-piperidinyl, lower alkyl substituted by halogen, -N=N-phenyl, di-lower alkylamino, (CH2)1.2-di-lower alkylamino, (CH2)2-NH-lower alkyl, NHC(O)-lower alkyl, lower alkoxy substituted by halogen, CH(CH3) C(O)O-lower alkyl, O-phenyl, O-benzyl, phenyl, optionally substituted CF3, SF5, benzyl, C(O)-lower alkyl, C(O)-phenyl, C(O)-morpholinyl, C(O)-4-methylpiperazinyl, C(O)-di-oxothiomorpholinyl, C(O)-piperidinyl, optionally substituted by F, C(O)-NH-(CH2)2-morpholinyl, C(O)-NR-(CH2)2-NR2, C(O)-N-di-lower alkyl, CH2-O-(CH2)2-4-methylpiperazinyl, CH2-O-(CH2)2-di-alkylamino, CH2-O-(CH2)2-pyrrolidinyl, CH2-O-(CH2)2-morpholinyl, CH2-O-(CH2)2-piperidinyl optionally substituted by lower alkyl substituted by halogen or lower alkyl, (CH2)3,4-pyrrolidin
