Nitropyridinyl ethyleneimine compound, the pharmaceutical composition containing it, the preparation method and use thereof

A method for preparation of a compound as shown in the formula 6 or the pharmaceutically acceptable salt thereof, characterized in that said method comprises the following steps:

• a) diazolizing a compound as shown in the formula 1 so that the amino group in the compound as shown in the formula 1 is converted into a phenolic hydroxyl group, yielding a compound as shown in the formula 2;
• b) reacting a compound as shown in the formula 2 at elevated temperature with a phosphorus halide, halogenated sulfoxide, organic acyl halide, or sulfonyl halide, yielding a compound shown in the formula 3, wherein X in the compound 3 is a halogen or OSO2R1 in which R1 is C1-6 aliphatic group, C3-6 saturated cyclic substituent, or aromatic group;
• c) oxidizing the methyl group in the compound of formula 3 into a carboxyl group, yielding a compound of formula 4;
• d) converting the carboxyl group in the compound of formula 4 into an amide group, yielding a compound of formula 5;
• e) reacting the compound of formula 5 with ethyleneimine in an organic solvent at 20-25° C. to yield a compound of the formula 6.