[H-].[Na+].[CH3:3][C:4]1[N:5]([CH2:11][CH2:12][OH:13])[C:6]([CH3:10])=[C:7]([CH3:9])[N:8]=1.Cl[CH2:15][C:16](=[O:23])[CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19].Cl>O1CCCC1>[CH3:3][C:4]1[N:5]([CH2:11][CH2:12][O:13][CH2:15][C:16](=[O:23])[CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19])[C:6]([CH3:10])=[C:7]([CH3:9])[N:8]=1Sodium hydride (80% dispersion in oil) (7.8 g) was suspended in dry tetrahydrofuran (100 ml). 2-(2,4,5-Trimethylimidazol-1-yl)ethanol (20 g) was added and the suspension sonicated until there was no further gas evolution. Ethyl 4-chloroacetoacetate (21.3 g) in dry tetrahydrofuran (25 ml) was added over 0.75 hours with sonication, and sonication continued for a further 4 hours. The suspension was poured into 2N hydrochloric acid (200 ml) and the tetrahydrofuran removed under vacuum. The aqueous solution was washed with dichloromethane (3×50 ml) and then neutralised with potassium carbonate. The aqueous phase was extracted with dichloromethane (5×100 ml), the combined organic extracts dried over magnesium sulphate and solvent removed under vacuum. The crude product was chromatographed over silica eluting with a mixture of methanol and ethyl acetate (1:3) to yield the title compound as a pale red oil 13.5 g (37%).
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