FUSED PYRIDAZINE COMPOUNDS AND THEIR MEDICINAL USES.

摘要

Novel fused pyridazine compounds represented by general formula (I) (wherein R<1>, R<2>, R<3> and R<4>, which may be the same or different, each represents hydrogen, halogen, hydroxy, nitro, amino, cyano, trifluoromethyl, alkyl, alkoxy or alkanoylamino, one of Ra and Rb represents -O-Y-NR<5>R<6> (wherein R<5> and R<6>, which may be the same or different, each represents hydrogen, alkyl, phenylalkyl or substituted phenylalkyl or, when taken together, R<5> and R<6> represent a group capable of forming a heterocyclic ring together with the adjacent nitrogen atom, and Y represents straight-chain or branched alkylene optionally having hydroxy group(s) on the chain as the substituent) and the other represents H, or Ra and Rb, which may be the same or different, each represents -O-Y-NR<5>R<6> (wherein R<5> and R<6> are as defined above), W represents =CH- or =N-, X represents CH2, S, SO, SO2 or O, and the bond represented by a dotted line represents a single bond or a double bond), pharmaceutically acceptable salts or hydrates thereof, and their medicinal uses are disclosed. These compounds have the action of increasing phagocytosis of leucocytes, that of increasing phagocytosis of macrophage, that of restoring the number of leucocytes, an infection protective action, an antitumor action, etc., and can be used for prophylaxis or treatment of diseases including human immunodeficiency.