1: indole With lithium hexamethyldisilazane in tetrahydrofuran; hexane T=-15°C; 1.16667 h; 2: 3,4-dibromo-N-methylmaleimide in tetrahydrofuran; hexane T=-15 - 20°C; 0.583333 h; 3: With hydrogenchloride in tetrahydrofuran; hexane; water pH=7;