| 主权项 |
1. A compound represented by the formula:or a pharmaceutically acceptable salt thereof, wherein
R1 is C1-C5-alkyl-Y or C2-C5-alkenyl-Y, where Y is H; optionally substituted aryl, optionally substituted heterocyclyl; —OC(O)R5; NR5R6; OH; —O—(CH2)n—W, where n is 1 to 4 and W is heterocyclyl; —OC(O)NR5R6; —C(O)H; —CH═NOZ, where Z is H, or alkyl, aryl, arylalkyl, heteroaryl or heteroarylalkyl, each optionally substituted; —CH(OR5)2; —SC(O)R5; —SH; —OSO2R5; —C(O)OH; or —C(O)N(R8)OH, where R8 is hydrogen or C1-C4-alkyl; N3; —CN; or halogen;
A is (a) C3-C4-alkyl-X, where X is H; OH; optionally substituted phenyl; optionally substituted —O-phenyl; optionally substituted —S-phenyl; optionally substituted 5-membered heteroaryl; optionally substituted —O-5-membered heteroaryl; optionally substituted —S-5-membered heteroaryl; —OC(O)NR5R6, —NHC(O)OR5, C(O)OR7, —OC(O)OR7, —CN, —N3, —C(O)NR5R6, —C(O)R5, optionally substituted —OSO2-phenyl, —NHC(O)R5 or —NR5R6; or (b) C3-C4-alkenyl-X′, where X′ is OH; optionally substituted phenyl; optionally substituted —O-phenyl; optionally substituted —S-phenyl; optionally substituted 5-membered heteroaryl; optionally substituted —O-5-membered heteroaryl; optionally substituted —S-5-membered heteroaryl; —OC(O)NR5R6, —NHC(O)OR5, C(O)OR7, —OC(O)OR7, —CN, —N3, —C(O)NR5R6, —C(O)R5, optionally substituted —OSO2-phenyl, —NHC(O)R5, or —NR5R6; each R5 and R6 is independently H; optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted arylalkyl or optionally substituted heteroarylalkyl; alternatively, R5, R6 and the nitrogen atom to which they are attached form an optionally substituted heterocyclic; R7 is optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted arylalkyl or optionally substituted heteroarylalkyl; andR2, R3 and R4 are independently selected from: hydrogen and methyl. |
