1: 1-methyl-5-nitro-1H-indole; 3-methoxy-4-bromomethyl-benzoic acid methyl ester With copper(I) oxide in 1,4-dioxane T=95 - 100°C; Friedel Crafts alkylation; Large scale reaction; 2: With hydrogen in ethyl acetate T=25 - 30°C; P=3677.86 - 4413.43 Torr; Large scale reaction; 3: 2-toluenesulfonamide; cyclopentyl Chloroformate Further stages;