摘要 |
To provide a compound which exhibits excellent anti-tumor activity and excellent oral absorption and which is a useful anti-tumor drug. The invention provides a 3′-ethynylcytidine derivative represented by formula (1): (wherein X represents a (substituted) alkylcarbonyl group, a (substituted) alkoxycarbonyl group, or a hydrogen atom; one of Y and Z represents a hydrogen atom or a group represented by (R1)(R2)(R3)Si— and the other represents a group represented by (R4)(R5)(R6)Si—; and R1, R2, R3, R4, R5, and R6 each represent a (substituted) alkyl group, a (substituted) cyclic alkyl group, or a (substituted) aryl group) or a salt thereof. |