To a solution of 5-chloro-1H-pyrrolo[2,3-c]pyridine-2-carboxylic acid (Preparation 18, 520 mg, 2.65 mmol) and 2-amino-3-(tert-butyldimethylsilanyloxy)-1-phenylpropan-1-ol (Preparation 99, 780 mg, 2.77 mmol) in DMF (15 mL) was added HOBt (411 mg, 2.68 mmol), DIPEA (0.96 mL, 5.51 mmol) and EDCI (589 mg, 3.07 mmol). After stirring at rt for 12 h the mixture was added to diluted brine (150 mL, water/brine:1/1). Extraction with ethyl acetate (4×50 mL), washing of the combined extracts with diluted hydrochloric acid (1M, 50 ml), diluted aqueous sodium hydroxide solution (1M, 50 ml) and brine (50 mL) followed by drying (MgSO4) gave after concentration a residue which was purified by flash chromatography on silica gel (eluent:hexane/ethyl acetate: 50/50). The title compound was obtained as colourless oil. δH (CD3OD): 0.00, 0.01 (6H, 2s), 0.84 (9H, s), 3.60 (1H, dd), 3.84 (1H, dd), 4.33 (1H, ddd), 4.98 (1H, d), 7.05 (1H, s), 7.12–7.37 (5H, 3m), 7.60 (1H, s), 8.49 (11H, s); m/z (ES+)=460.36 [M+H]+; RT=4.16 min.
