| 主权项 |
1. A compound represented by formula I: or a pharmaceutically acceptable salt thereof, wherein
Rb is selected from the group consisting of H, halogen, hydroxyl, cyano and C1-C6alkyl;R is H, C1-C6 alkyl or —C(O)—C1-C6alkyl;R1 is H or C1-C6 alkyl;R2 is H or C1-C6 alkyl;R3 is C1-C6 alkyl; C1-C6 alkoxy; —O—C1-C6 alkylene-phenyl; C2-C6 alkenyl; C2-C6 alkynyl; C3-C6 cycloalkyl; phenyl; or heteroaryl including from 5 to 6 ring atoms wherein 1, 2, or 3 of the ring atoms are independently selected from the group consisting of N, NH, N(C1-C3 alkyl), O, and S; wherein R3 is optionally substituted with one, two, or three substituents independently selected from the group consisting of amino, protected amino, halogen, C1-C6 alkyl, C1-C6 alkoxy, hydroxyl, phenyl (optionally substituted by one, two, or three substituents each independently selected from Ra), benzyl (optionally substituted by one, two, or three substituents each independently selected from Ra), and —C1-C6 alkylene-C3-C6 cycloalkyl (optionally substituted by one, two or three substituents independent selected from halogen and C1-C6 alkyl);Ra is selected from the group consisting of halogen, C1-C6alkyl (optionally substituted by one, two or three halogens), C3-C6 cycloalkyl (optionally substituted by one, two or three halogens), and C1-C6 alkoxy (optionally substituted by one, two or three halogens);R4 is H or C1-C6 alkyl;R5 is H or C1-C6 alkyl;X is selected from the group consisting of: H; C1-C6 alkyl; —OH; C1-C6 alkoxy; —CO2H; —C(O)NRcRd; and heteroaryl including from 5 to 6 ring atoms wherein 1, 2, or 3 of the ring atoms are independently selected from the group consisting of N, NH, N(C1-C3 alkyl), O, and S, wherein the heteroaryl ring may be optionally substituted with one, two, or three substituents independently selected from the group consisting of halogen, C1-C6 alkyl, C1-C6 alkoxy, hydroxyl and phenyl; andRc and Rd are each independently selected from the group consisting of H, C1-C6 alkyl, or phenyl, or Rc and Rd together with the nitrogen to which they are attached, form heterocyclyl including from 4 to 6 ring atoms; wherein the heterocyclyl includes not more than two ring heteroatoms (including the nitrogen atom attached to Rc and Rd), and the second ring heteroatom, when present, is independently selected from the group consisting of N, NH, N(C1-C3 alkyl), O, and S; and wherein the heterocyclyl is optionally substituted with from 1-3 substituents independently selected from the group consisting of halogen, cyano, oxo, and C1-C6 alkyl. |
