2-Ethylcyclopentane-1,3-dione → (2S)-Ethyl-3-[4-(3-ethyl-isoquinolin-1-ylamino)phenyl]-2-[(2-ethyl-3-oxo-1-cyclopentenyl)amino]propionate

Participants

Reaction Steps

A solution of (S)-ethyl-3-[4-(3-ethyl-isoquinol-1-yl amino)phenyl]-2-aminopropionate [prepared from 1-chloro,3-ethyl-isoquinoline (from reaction of o-toluic acid with propionitrile and subsequent treatment with phosphorous oxychloride) and N-BOC-L-4-aminophenylalanine ethylester] (750 mg, 2.07 mmol) and 2-ethyl-1,3-cyclopentanedione (273 mg, 2.17 mmol) in 1,2-dichloroethane (10 ml) was treated with 4 Å sieves (˜1 g) and heated at 90° for 3 days. The solution was filtered, concentrated in vacuo and the residue purified by chromatorgaphy (SiO2, 100:1 DCM/MeOH) to give the title compound as a brown solid (511 mg, 52%). δ H (d6-DMSO) 9.05 (1H, s), 8.46 (1H, d, J 7.0 Hz), 7.91 (2H, d, J 8.6 Hz), 7.72 (1H, d, J 7.0 Hz), 7.64 (1H, t, J 7.0 Hz), 7.51 (1H, t, J 7.0 Hz), 7.23 (2H, d, J 8.6 Hz), 6.99 (1H, s), 4.32 (1H, m), 4.15 (2H, q, J 7.1 Hz), 3.15 (1H, dd, J 13.5, 3.5 Hz), 3.01 (1H, dd, J 13.5, 9.6 Hz), 2.69 (2H, 1, J 7.5 Hz), 2.29 (1H, m), 2.18 (1H, m), 2.06 (4H, m), 1.28 (3H, t, J 7.5 Hz), 0.91 (3H, t, J 7.4 Hz). m/z (ESI, 70V) 472 (MH+).

Provenance & Evidence