| abstract |
The present invention relates to a compound represented by the following formula (1),n□ [In the above formula, X represents an oxygen atom, an imine group, a sulfur atom, a sulfinyl group or a sulfonyl group, and R1, R2 and R3 each independently represent a hydrogen atom or a C1-C6 alkyl group, and R4 represents a hydrogen atom, An alkyl or aralkyl group of C1-C6, and R5 represents an alkyl group, an alkenyl group, an alkynyl group, an aryl group, a heteroaryl group]. This compound has an excellent EPO production promoting action and is useful as a drug. |