1,1'-Carbonyldiimidazole → (S)-N-[5-(4-Methylpiperazin-1-yl)-3,4-dihydro-2H-1-benzopyran-3-yl]-4-(4-benzylpiperazin-1-yl)benzamide

Participants

Reaction Conditions

Reaction Steps

A suspension of 4-(4-benzylpiperazin-1-yl)benzoic acid (1.3 g, 4.2 mmol) and 1,1′-carbonyldiimidazole (740 mg, 4.2 mmol) in N,N-dimethylformamide (30 mL) was heated to 75° C. for 1.5 h. The reaction mixture was cooled to 50° C. and a solution of (S)-3-amino-5-(4-methylpiperazin-1-yl)-3,4 dihydro-2H-1-benzopyran (1.0 g, 4.0 mmol) was added. The solution was stirred at 50° C. for 20 h and the solvent was evaporated in vacuo giving 3.5 g of a crude product. Purification by chromatography on a silica gel column using chloroform/methanol/concentrated ammonia 95:5:0.5 as the eluent gave 1.7 g (80% yield) 25 of the title compound as a pale yellow solid: mp sinters >85° C.; TSPMS m/z (relative intensity) 526 (100, M+1); [α]22D−130° (c 1.0, chloroform).

Provenance & Evidence