Trifluoroacetic acid → HCID 90404321, compound

Participants

Reaction Steps

Ethyl 4-(1-(tert-butoxycarbonyl)piperidin-4-ylamino)-2-(2,2,2-trifluoroethyl)thieno[2,3-b]pyridine-5-carboxylate (45 mg, 0.1 mmol) was dissolved in CH2Cl2 (3 mL). Trifluoroacetic acid (2 mL) was added to the solution. After 2 hours, the solution was concentrated in vacuo. The residue was dissolved in CH2Cl2 (10 mL), and washed with a 10% solution of K2CO3 (2×1 mL), and dried over anhydrous K2CO3. The organic phase was concentrated to give tan residue, which was used in the next step without further purification. This residue was dissolved in 1,2-dichloroethane (1 mL). 5-formyl-1H-indole-2-carbonitrile (23 mg, 0.14 mmol) and sodium tri(acetoxy)borohydride (32 mg, 0.15 mmol) were added. The mixture was stirred at room temperature for 2 hours. The solution was diluted with EtOAc (10 mL) and washed with 0.1 N NaOH (1×5 mL). The organic phase was dried over Na2SO4 and concentrated in vacuo. The resulting residue was purified by reversed-phase preparative HPLC (95:5-5:95 MeCN/H2O with 0.1% HCl buffer). The product containing fractions were lyophilized to afford the product as a white solid (1.4 mg, 2.5% yield), Compound 278. LC-MS: 1.45 min, 500.2 m/z [M+H]+.

Provenance & Evidence