Sodium Carbonate → HCID 135738577, compound

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Reaction Steps

5-(2-Ethoxyphenyl)-3-methoxymethyl-1-methyl-1,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one (470 mg, 1.50 mmol) was dissolved in chlorosulphonic acid (3 ml) at 0° C. The solution was stirred at room temperature for 2 hours, then cautiously added to ice-water (50 ml). The resulting solution was neutralised with saturated sodium carbonate solution, then extracted with a 20:1 mixture of dichloromethane and methanol (2×50 ml). The combined organic extracts were evaporated under vacuum and the residue was dissolved in ethanol (5 ml) and the solution treated with N-methylpiperazine (450 mg, 4.5 mmol). After 1 hour at room temperature the solvent was evaporated under vacuum and the residue chromatographed on silica gel, eluting with a mixture of dichloromethane, methanol and aqueous ammonium hydroxide solution (90:10:1 by volume). Trituration of the crude product with ethyl acetate gave the title compound as a white solid (49 mg, 7%), m.p. 198°-199° C. Found: C,52.94; H,6.04; N,17.67. C21H28N6O5S requires C,52.93; H,5.92; N,17.64%.

Provenance & Evidence