FIELD: organic chemistry, medicine, hematology. SUBSTANCE: invention describes novel compounds of amidine of the formula (I) 
where R represents group of formulas (a) 
, (b) 
or (c) 
; R4 is hydrogen or halogen atom; R5 is hydrogen atom, cyano-, carboxy- or lower alkoxycarbonyl-group; R6 is hydrogen atom, hydroxy-, carboxy-, lower alkoxycarbonyl-group, phenyl group that is optionally substituted with amidino-group; pyridyl that is optionally substituted with 1-3 substituents taken among lower alkyl group, benzoylamino-group, quinolyl, pyrimidyl; X2 is oxygen atom, sulfur atom; X3 means (CH2)m where m = 0, whole number from 1 to 3; X4 means -C(=NH)-, -SO2NH-, pyridinyl or a linear bond; X5 means alkylene group containing 1-6 carbon atoms, alkenylene group containing 2-6 carbon atoms or a linear bond; R7 is hydrogen atom or group 
where R9 means NH, NR11 where R11 is lower alkyl group, benzyl group; R10 is lower alkyl group or amino-group; R8 is cycloalkyl group optionally substituted with carboxy-group; phenyl group, benzyl group; Y1 means oxygen atom or NR12; 
are hydrogen atom, lower alkyl group, phenyl group substituted with carboxy-group or lower alkoxycarbonyl group, -, or -(Y6 means CO-, COCO2 or (CH2)r) where r = 0, 1; Y2 means oxygen atom or linear bond; Y3 means pyridinyl or 
where s and t are similar or different and each is a whole number from 1 to 3; Y4 means CO-, CONH-, -CH= CH-; Y5 means 
or 
where Ak is lower alkyl group; p = 0 or whole number from 1 to 3; p″ = 0; A means group of formulas 
or 
; j = 1; k = 0; m and n are similar and each is whole number 1; R1, R2, R3 are similar or different and each represents hydrogen atom or hydroxy-group or its salt. Compounds show inhibitory activity with regards to blood coagulation Xa factor. Invention describes also pharmaceutical composition exhibiting inhibitory effect of Xa factor based on claimed compounds. EFFECT: valuable medicinal properties of compounds and pharmaceutical composition. 12 cl, 15 tbl
