6-[5-(2-aminoethyl)-2-oxo-3-oxazolidinyl]-2H-1,4-benzothiazin-3(4H)-one 以26%的产率得到rac-(E)-3-[1-methyl-2,4-dioxo-3-(2-{2-[2-oxo-3-(3-oxo-3,4-dihydro-2H-benzo[1,4]thiazin-6-yl)-oxazolidin-5-yl]-ethylamino}-ethyl)-1,2,3,4-tetrahydro-quinazolin-7-yl]-acrylic acid methyl ester