Compounds represented by general formula (I) and medicinal preparations, in particular, platelet aggregation inhibitors, blood coagulation inhibitors for systemic circulation, and coronary reinfarction inhibitors, wherein A represents a tertiary amine; R3 represents hydrogen, lower alkyl, lower alkenyl, lower alkynyl, lower aralkyl, or aryl; R4 represents hydrogen, optionally substituted lower alkyl, lower alkenyl, lower alkynyl, optionally substituted lower aralkyl, optionally substituted lower aralkenyl, optionally substituted lower aralkynyl, optionally substituted aryl, optionally substituted heterocycle, optionally substituted cycloalkyl, optionally substituted cycloalkenyl, optionally substituted cycloalkynyl or lower alkoxy; P and Q represent each lower alkyl or P and Q are combined to form cycloalkyl together with the adjacent carbon atom; R5 represents hydrogen or a carboxy-protective group; X represents nitrogen or CH; Y1 and Y2 represent each hydrogen, lower alkyl, halogeno, hydroxy, lower alkoxy, lower acyloxy, acyl, carboxy, lower alkoxycarbonyl, nitro or trifluoromethyl; and m is an integer of 0 to 2.