1,2-Dichloroethane → [5-(2-oxo-hexahydro-thieno[3,4-d]imidazol-6-yl)-pentanoylamino]-thioacetic acid S-benzyl ester

Participants

Reaction Steps

Biotin 19 (0.156 g, 0.64 mmol) was dissolved in 40 mL of dry THF. To this solution was added EDC (0.123 g, 0.64 mmol) and HOBt (0.098 g, 0.64 mmol) under ice-cold conditions. The reaction was allowed to stir for 30 minutes, followed by addition of 8 (0.139 g, 0.64 mmol) dissolved in minimal amount of DMF. The resulting solution was allowed to stir overnight at RT. Upon removal of the solvent in vacuo, the residue was taken into ethyl acetate and washed with 1 N HCl (2×30 ml), water (2×30 ml) and brine (2×30 ml). The organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure to afford 5 (0.110 g, 42%). 1H-NMR (300 MHz, DMSO) δ 7.31-7.28 (m, 5H), 6.40-6.35 (broad, 2H), 4.37-4.32 (m, 2H), 4.22 (d, J=5.61 Hz, 2H), 4.09 (s, 2H), 3.1-3.0 (m, 1H), 2.88-2.78 (m, 2H), 2.19-2.14 (m, 2H), 1.60-1.48 (m, 6H). MS (ESI): m/z 408.0 [(M+1)]+.

Provenance & Evidence