1-Boc-5-hydroxyindole

5 -Hydroxy-indole- 1-carboxylic acid tert-butyl ester; [0464] A solution of the product of Example 93 A (680 mg, 2.103 mmol) in ethanol (20 mL) was treated with 10percent palladium-on-carbon (68 mg) and ammonium formate (265 mg, 4.205 mmol), and stirred at room temperature under a nitrogen atmosphere for 1 hour. The reaction was filtered through a 0.45 μ PTFE membrane and the catalyst washed with methanol. The filtrate was concentrated by rotary evaporation under vacuum and the residue taken up in ethyl acetate (50 mL), washed with water (2 x 25 mL) and brine (25 mL), dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum to provide the title compound as a white solid (475 mg, 96percent).ferf-Butyl 5-(benzyloxy)-1H-indole-1-carboxylate (5.75 g, 17.8 mmol), preparedaccording to the procedure described for Example 1, step 1, was added to a mixture of10percent Pd/C in EtOH. Ammonium formate was added and the reaction stirred for 6 h. Themixture was filtered through Celite.(R). under a blanket of argon and the solvents were thenremoved. The residue was purified by flash chromatography to yield 3.5 g of ferf-butyl 5-hydroxy-1H-indole-1-carboxylate (74percent). 5-Hydroxyindole (3.49 g, 26.2 mmol) was dissolved in acetonitrile (35.0 mL), and the solution was added with di-tert-butyldicarbonate (18.1 mL, 78.6 mmol) and DMAP (294 mg, 2.62 mmol), followed by stirring at room temperature for 4 hours. The reaction mixture was concentrated under reduced pressure, and the residue was dissolved in methanol (130 mL) and added with potassium carbonate (18.1 g, 131 mmol), followed by stirring at room temperature for 4 hours. The mixture was added with acetic acid (7.50 mL) to neutralize, and then added with water, followed by extracting with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The residue was purified by flash column chromatography (hexane/ethyl acetate=2/1) to obtain 1-(tert-butoxycarbonyl)-5-hydroxyindole (5.74 g, 94percent). ESI-MS m/z: 234 [M+H]To a solution of 5-hydroxyindole (2.02 g, 15.2 mmol, 1.0 eq) in MeCN (20 mL)was added di-tert-butyl dicarbonate (9.93 g, 45.5 mmol, 3.0 eq) and DMAP (186mg, 1.52 mmol, 10 molpercent). The reaction mixture was stirred at rt for 1 h then concentrated in vacuo, re-dissolved in CH2CI2 (20 mL) and washed with H20 (20 mL). The aqueous phase was extracted with CH2CI2 (20 mL) and the combined organic extracts were dried over MgSO4, filtered and concentrated in vacuo. Theresidue was then dissolved in MeOH (100 mL) and cooled to 0°C before the addition of potassium carbonate (10.5 g, 76 mmol, 5.0 eq) portionwise. The reaction was allowed to warm to rt and stirred for 1.5 h, then re-cooled to 0°C and quenched by the dropwise addition of acetic acid to neutralise the mixture. H20 (100 mL) was added and the resulting mixture was extracted with EtOAc (3x 100 mL). The combined organic extracts were dried over MgSO4, filtered and concentrated in vacuo. Purification twice by silica gel chromatography using hexane/EtOAc (1:0-6:1) then hexane/CH2CI2 (1:0-1:4) yielded Intermediate 49 as a white solid (3.05 g, 86percent).1H NMR (300MHz, DMSO-d5) oH. 9.18 (5, 1H), 7.82 (d, J=8.9 Hz, 1H), 7.55 (d, J=3.8 Hz, 1H), 6.92 (d, J=2.4 Hz, 1H), 6.77 (dd, J=8.9, 2.4 Hz, 1H), 6.54 (d, J=3.8 Hz, 1H), 1.56-1.64 (m, 9H).MS (ESj 256.1 (40percent, [M+Na]j.A solution of 5-hydroxyindole (III-1) (10 g, 75.1 mmol) in 100 mL of acetonitrile was added di-tert-butyl dicarbonate (49.2 g, 225.3 mmol) and DMAP (917 mg, 7.51 mmol) was stirred at room temperature for 15h; after completion of the reaction, the reactionmixture was concentrated under reduced pressure and 400mL of methanol was added to dissolve, then add K