1H-1,2,4-triazole derivatives and 1H-pyrrolo- 1,2-b 1,2,4 triazole derivatives

摘要

The novel 1H-pyrroloÄ1,2-bÜÄ1,2,4Ütriazole derivative represented by formula (III) CHEM wherein R1 represents an aliphatic group which may be substituted or an aryl group which may be substituted; R2 and R3 each represents an electron-withdrawing group having a Hammett's substituent constant sigma p of from 0.2 to 1.0; Y represents -C(=O)-R5, -SO2R6 or -P(=O)(R7)(R8), wherein R5, R7 and R8 each represents a hydrogen atom, an aliphatic group which may be substituted, an aryl group which may be substituted, an aliphatic oxy group which may be substituted, an aryloxy group which may be substituted, or a group represented by -N(Ra')Ra, and R7 and R8 may be bonded to each other to form a ring; and R6 represents an aliphatic group which may be substituted, an aryl group which may be substituted, or a group represented by -N(Ra')Ra, and wherein Ra and Ra' each represents a hydrogen atom, an aliphatic group which may be substituted, or an aryl group which may be substituted, and Ra and Ra' may be bonded to each other to form a ring, which is useful as an intermediate for physiologically active substances can be efficiently synthesized by using as intermediates the novel 1H-1,2,4-triazole derivatives represented by formulae (I) and (II) CHEM wherein R1 represents an aliphatic group which may be substituted or an aryl group which may be substituted; R2 and R3 each represents an electron-withdrawing group having a Hammett's substituent constant sigma p of from 0.2 to 1.0; R4 represents a hydrogen atom, an aliphatic group, or an aryl group; and X represents a halogen atom. The 1H-pyrroloÄ1,2-bÜÄ1,2,4Ütriazole derivative represented by formula (III) according to the present invention has a pKa value higher by about 1 than that of the 5-chloro-substituted corresponding compound and is thermally stable.