Amino acid active ester and salt thereof

A compound represented by formula (Ia):

• wherein:
• X is pyridyl substituted with two or more halogen atoms, or a C1-3 alkyl substituted with three or more fluorine atoms;
• Z is —NR5R6 or —ORd;
• Q is a group represented by
• n is an integer from 0 to 3, and preferably an integer from 0 to 2;
• R7 and R8 are each independently selected from a hydrogen atom or a C1-3 alkyl;
• R1 and R2 are each independently selected from a hydrogen atom, a halogen atom, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y1, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y2, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y2, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y2, a C6-14 aryl optionally substituted with one or more substituents selected from Y3, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y3, —COOR11, and —CONR12R13;
• or
• R1 and R5, together with the carbon atom and the nitrogen atom, respectively, to which they are attached, form a 3- to 10-membered non-aromatic heterocyclic ring optionally substituted with one or more substituents selected from Y2;
• when n is an integer from 1 to 3, R1 and any one of R3, together with the carbon atoms to which they are attached, form a C3-10 carbocyclic ring optionally substituted with one or more substituents selected from Y2, or a 3- to 10-membered non-aromatic heterocyclic ring optionally substituted with one or more substituents selected from Y2;
• R1 and R2, together with the carbon atom to which they are attached, form a C3-10 carbocyclic ring optionally substituted with one or more substituents selected from Y2, or a 3- to 10-membered non-aromatic heterocyclic ring optionally substituted with one or more substituents selected from Y2;
• R3 and R4 are each independently selected from a hydrogen atom, a halogen atom, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y1, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y2, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y2, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y2, a C6-14 aryl optionally substituted with one or more substituents selected from Y3, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y3, —COOR11, and —CONR12R13;
• or
• R3 and R4, together with the carbon atom to which they are attached, form a C3-10 carbocyclic ring optionally substituted with one or more substituents selected from Y2, or a 3- to 10-membered non-aromatic heterocyclic ring optionally substituted with one or more substituents selected from Y2;
• when n is an integer from 1 to 3, R5 and any one of R3, together with the nitrogen atom and the carbon atom to which they are attached, form a 3- to 10-membered nitrogen-containing non-aromatic heterocyclic ring optionally substituted with one or more substituents selected from Y2;
• R11, R12 and R13 are each independently selected from a C1-10 alkyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y1, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y2, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y2, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y2, a C6-14 aryl optionally substituted with one or more substituents selected from Y3, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y3;
• each Y1 is independently selected from a halogen atom, nitro, cyano, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6, —SH, —COOR21, —NR22R23, —N3, —S(O)pR24, —OR25, —SO2NR26R27 and —CONR28R29, and oxo;
• each Y2 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6, —SH, —COOR21, —NR22R23, —S(O)pR24, —OR25, —SO2NR26R27 and —CONR28R29, and oxo;
• each Y3 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6, —SH, —COOR21, —NR22R23, —S(O)pR24, —OR25, —SO2NR26R27 and —CONR28R29;
• R21, R26, R27, R28 and R29 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6;
• R22 and R25 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6, —CORa1, —CONRa2Ra3, —COORa4, —C(═NRa5)NRa6Ra7, —S(O)pR24 and —SO2NRa8Ra9;
• R23 is selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6;
• R24 is selected from a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6;
• Ra1, Ra2, Ra3, Ra4, Ra5, Ra6, Ra7, Ra8 and Ra9 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y4, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y4, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6;
• each Y4 is independently selected from a halogen atom, nitro, cyano, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y5, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y5, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y5, a C6-14 aryl optionally substituted with one or more substituents selected from Y6, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y6, —SH, —COOR31, —NR32R33, —S(O)pR34, —OR35, —SO2NR36R37 and —CONR38R39, and oxo;
• each Y5 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9, —SH, —COOR31, —NR32R33, —S(O)pR34, —OR35, —SO2NR36R37, —CONR38R39, and oxo;
• each Y6 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9, —SH, —COOR31, —NR32R33, —S(O)pR34, —OR35, —SO2NR36R37, and —CONR38R39;
• R31, R36, R37, R38 and R39 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9;
• R32 and R35 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9, —CORb1, —CONRb2Rb3, —CO2Rb4, —C(═NRb5)NRb6Rb7 and —SO2NRb8Rb9;
• R33 is selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9;
• R34 is selected from a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9;
• Rb1, Rb2, Rb3, Rb4, Rb5, Rb6, Rb7, Rb8 and Rb9 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y7, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y7, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y8, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y8, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y8, a C6-14 aryl optionally substituted with one or more substituents selected from Y9, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y9;
• each Y7 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12, —SH, —COOR40, —NR41R42, —S(O)pR43, —OR44, —SO2NR45R46 and —CONR47R48, and oxo;
• each Y8 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12, —SH, —COOR40, —NR41R42, —S(O)pR43, —OR44, —SO2NR45R46, —CONR47R48, and oxo;
• each Y9 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12, —SH, —COOR40, —NR41R42, —S(O)pR43, —OR44, —SO2NR45R46 and —CONR47R48;
• R40, R45, R46, R47 and R48 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12;
• R41 and R44 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12, —CORc1, —CONRc2Rc3, —COORc4, —C(═NRc5)NRc6Rc7, and —SO2NRc8Rc9;
• R42 is selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12;
• R43 is selected from a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12;
• Rc1, Rc2, Rc3, Rc4, Rc5, Rc6, Rc7, Rc8 and Rc9 are each independently selected from a hydrogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y10, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y10, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y11, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y11, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y11, a C6-14 aryl optionally substituted with one or more substituents selected from Y12, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y12;
• each Y10 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkoxy optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C6-14 aryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a (C1-10 alkoxy)carbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a di(C1-6 alkyl)aminocarbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkoxy optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylthio optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfanyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfinyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, and oxo;
• each Y11 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C2-10 alkenyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C2-10 alkynyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C1-10 alkoxy optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C6-14 aryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a (C1-10 alkoxy)carbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a di(C1-6 alkyl)aminocarbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkoxy optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylthio optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfanyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfinyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, and oxo;
• each Y12 is independently selected from a halogen atom, nitro, cyano, a C1-10 alkyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C2-10 alkenyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C2-10 alkynyl optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C1-10 alkoxy optionally substituted with one or more substituents selected from a halogen atom and an alkoxy, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C6-14 aryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a (C1-10 alkoxy)carbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a di(C1-6 alkyl)aminocarbonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkoxy optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylthio optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfanyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, a C1-6 alkylsulfinyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy, and a C1-6 alkylsulfonyl optionally substituted with one or more substituents selected from a halogen atom and a C1-6 alkoxy;
• each p is independently an integer from 0 to 2;
• R5 is selected from a hydrogen atom, benzyl optionally substituted on the benzene ring with one or more substituents selected from Y13, benzyloxycarbonyl optionally substituted on the benzene ring with one or more substituents selected from Y13, phenylcarbonyl and (C1-10 alkoxy)carbonyl optionally substituted with one or more substituents selected from Y13, (C1-10 alkyl)carbonyl optionally substituted with a halogen atom, a C1-10 alkyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkenyl optionally substituted with one or more substituents selected from Y1, a C2-10 alkynyl optionally substituted with one or more substituents selected from Y1, a C3-10 cycloalkyl optionally substituted with one or more substituents selected from Y2, a C3-10 cycloalkenyl optionally substituted with one or more substituents selected from Y2, a 3- to 14-membered non-aromatic heterocyclyl optionally substituted with one or more substituents selected from Y2, a C6-14 aryl optionally substituted with one or more substituents selected from Y3, and a 5- to 14-membered heteroaryl optionally substituted with one or more substituents selected from Y3;
• R6 is selected from a hydrogen atom, benzyl optionally substituted on the benzene ring with one or more substituents selected from Y13, benzyloxycarbonyl optionally substituted on the benzene ring with one or more substituents selected from Y13, and phenylcarbonyl, (C1-10 alkoxy)carbonyl and (C1-10 alkyl)carbonyl optionally substituted with one or more substituents selected from Y13;
• or
• R5 and R6, together with the nitrogen atom to which they are attached, form a 5- to 14-membered nitrogen-containing heterocyclyl having an imide structure, or a 3- to 14-membered non-aromatic heterocyclyl containing, as ring atoms, two or more nitrogen atoms optionally substituted with one or more substituents selected from Y2;
• Rd is selected from a hydrogen atom, benzyl optionally substituted on the benzene ring with one or more substituents selected from Y13, benzyloxycarbonyl optionally substituted on the benzene ring with one or more substituents selected from Y13, and phenylcarbonyl, (C1-10 alkoxy)carbonyl and (C1-10 alkyl)carbonyl optionally substituted with one or more substituents selected from Y13;
• each Y13 is independently selected from a halogen atom, C1-10 alkoxy, and C1-10 alkyl;
• when the 3- to 14-membered non-aromatic heterocyclyl is a monocyclic heterocyclyl, the heterocyclyl is optionally fused with a benzene ring;
• and
• when the C6-14 aryl is phenyl, the phenyl is optionally fused with a 5- to 7-membered non-aromatic heterocyclic ring;
• or a salt thereof, except for the compound of formula (Ia) wherein Z is hydroxy, n is 0, R7 and R8 are each hydrogen atom, X is 2,6-dichloropyridin-4-yl, and;
• R1 and R2 are each a hydrogen atom;
• or
• R1 is a hydrogen atom and R2 is methyl, ethyl, isopropyl, n-butyl, tert-butyl or isobutyl;
• or
• R1 is ethyl and R2 is methyl or ethyl.