Hydrazide compounds and thrombopoietin receptor activators

A compound represented by formula (I):

• wherein each of R1 and R2 is independently a hydrogen atom, a C1-6 alkyl group, a C1-6 alkoxy group, a halogenated C1-3 alkyl group, or a halogenated C1-3 alkoxy group;
• R3 is
• wherein each of R8 and R9 is independently a hydrogen atom or a C1-6 alkyl group, wherein the C1-6 alkyl group is optionally substituted with at least one substituent selected from the group consisting of a carboxyl group, a C1-6 alkoxy group, and a C2-14 aryl group, or
• R8 and R9 together are —(CH2)m1—E—(CH2)m2—, wherein E is CR10R11 wherein each of R10 and R11 is independently a hydrogen atom or a C1-6 alkyl group, and each of m1 and m2 is independently an integer of from 0 to 5, provided that m1+m2 is 2, 3, 4, or 5,
• or
• R3 is
• wherein R17 is a hydrogen atom or a C1-6 alkyl group, and R18 is an amino group, a mono- or di-C1-6 alkylamino group, or a C2-9 heterocyclyl group, or
• R17 and R18 together are —(CH2)m3—G—(CH2)m4—, wherein G is CR19R20, wherein R19 is a hydrogen atom, and R20 is an amino group, a mono- or di-C1-6 alkylamino group, or a C2-9 heterocyclyl group, each of m3 and m4 is independently an integer of from 0 to 5, provided that m3+m4 is 2, 3, 4, or 5, or
• NR17R18, as a whole, is a nitrogen-containing C2-9 cyclyl group which is substituted with two or three substituents selected from the group consisting of a hydroxyl group, an amino group, a protected amino group, and a C1-6 alkoxy group;
• R33 is a hydrogen atom, a C1-6 alkoxy group, a C1-6 alkyl group, a halogenated C1-3 alkyl group, or a halogenated C1-3 alkoxy group;
• and
• R34 is a phenyl group, which is optionally substituted with at least one substituent selected from the group consisting of a C1-6 alkyl group, a halogenated C1-6 alkyl group, a halogen atom, a C1-6 alkoxy group, and a halogenated C1-3 alkoxy group,
• or a tautomer or pharmaceutically acceptable salt of the compound.