1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → 9H-fluoren-9-ylmethyl N-[(2S)-1-[[(2S)-1-[[(E)-3-[(6aS)-3-[3-[[(6aS)-2-methoxy-8-[4-(4-methylpiperazin-1-yl)phenyl]-6,11-dioxo-5-(2-trimethylsilylethoxymethyl)-6a,7-dihydropyrrolo[2,1-c][1,4]benzodiazepin-3-yl]oxy]propoxy]-2-methoxy-6,11-dioxo-5-(2-trimethylsilylethoxymethyl)-6a,7-dihydropyrrolo[2,1-c][1,4]benzodiazepin-8-yl]prop-2-enyl]amino]-1-oxopropan-2-yl]amino]-3-methyl-1-oxobutan-2-yl]carbamate

Participants

Reaction Steps

1-Ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (0.0541 g, 0.282 mmol, 1.0 eq.) was added to a solution of allylamine 17e (assumed 100% yield, 0.296 g, 0.282 mmol, 1.0 eq.) and HO-Ala-Val-Fmoc 12 (0.116 g, 0.282 mmol, 1.0 eq.) in dry dichloromethane (18 mL). The reaction mixture was stirred for 80 minutes at room temperature when the reaction mixture was diluted with dichloromethane (30 mL) and washed sequentially with water (30 mL) and brine (30 mL). The organic layer was dried over MgSO4 filtered and excess dichloromethane removed under reduced pressure. The resulting residue was purified by flash chromatography (silica gel; 40:1 v/v DCM/MeOH to 20:1 v/v DCM/MeOH) to afford the product as a yellow solid (0.245 g, 60%). LC/MS (2.706 min (ES+)), m/z: 721.5 ½[M+2H]+.

Provenance & Evidence