| 主权项 |
1. A compound of formula I wherein R1 is chosen from
(a) C2-C10 hydrocarbon other than cyclopropylmethyl; and(b) —CH2—Het, wherein Het is a five- or six-membered heterocycle; R2 is chosen from hydrogen, (C1-C6)acyl, (C1-C6)oxaalkyl, and (C1-C6)acyloxaalky; R3 is chosen from hydrogen and (C1-C6)alkyl; R4 is chosen from (a) phenyl substituted at other than 2 or 6 with from one to three substituents chosen from amino, bromo, chloro, iodo, hydroxy, nitro, cyano, (C1-C3)alkyl, (C1-C3)haloalkyl, (C1-C3)haloalkoxy, (C1-C3)alkoxy and R10; (b) optionally substituted naphthylene; (c) optionally substituted anthracene; (d) optionally substituted aromatic heterocycle; R8 is chosen from hydrogen and (C1-C6)alkyl; R10 is optionally substituted phenyl, optionally substituted aromatic heterocycle or optionally substituted non-aromatic oxygen or sulfur heterocycle; wherein the substituents on naphthylene, anthracene, heterocycle or R10 are chosen independently from halogen, hydroxy, nitro, cyano, (C1-C3)alkyl, (C1-C3)haloalkyl, (C1-C3)haloalkoxy, (C1-C3)acyl and (C1-C3)alkoxy. |
