A compound having a structure of Formula (III): ** Formula ** in the form of an isolated stereoisomer or a mixture of stereoisomers or in the form of a pharmaceutically acceptable salt thereof, in which: R1 is substituted pyridinyl having one or more substituents independently selected from: cycloalkyl and C1-12 alkyl； substituted indolyl having one or more substituents independently selected from: phenyl, substituted phenyl, substituted benzyl, pyridinyl, sulfonyl, acetyl, acyl, carbonyl, C1-12 alkyl, acyloxy C1-12 alkyl, C1-12 alkoxy, halogen, monoxide and cyano, in which the substituted benzyl is nitro-benzyl or amino-benzyl, in which the sulfonyl is selected from the group consisting of tosyl, phenyl sulfonyl, C1-12 alkyl sulfonyl, C1-12 alkylsulfonylamino, aminosulfonylamino or halo- phenyl sulfonyl, wherein the carbonyl is selected from the group consisting of cycloalkylcarbonyl, C1-12 alkoxycarbonyl, morpholinylcarbonyl, aminocarbonyl, C1-12 alkylaminocarbonyl, C1-12 dialkylaminocarbonyl, C1-12 alkylaminocarbonyl, C2-13 alkylaminocarbonylcarbonylcarbonylcarbonyl -12, benzylaminocarbonyl, dihydropyrrolylcarbonyl, cycloalkyl-C1-12 alkylcarbonyl, cycloalkenyl-C1-12 alkylcarbonyl, C2-13 alkoxyalkylcarbonyl, imidazolyl aminocarbonyl, piperidinylcarbonyl, pyrrolidinylcarbonyl, alkoxyaminocarbonyl, hydroxyaminocarbonyl, C1-12 hydroalkylaminocarbonyl, hydrazinylcarbonyl, C1-12 alkylformiatohydrazinylcarbonyl or tetrahydrofuranoyl-C1-12 alkylaminocarbonyl； R4 is allyl； R6 is phenyl or substituted phenyl having one or more substituents independently selected from: halogen, hydroxyl, cyano, C1-6 alkyl and C1-6 alkoxy； or substituted pyridyl or pyridyl having one or more substituents independently selected from: halogen, hydroxyl, cyano, C1-6 alkyl and C1-6 alkoxy； X1 is hydrogen, hydroxyl or halogen； and each of X2 and X3 is independently hydrogen, hydroxy, dimethylaminoacetate, (2-dimethylamino-ethyl) -carbamate, diethyl-phosphono-acetamido or halogen, in which the alk
