1-Methylpiperazine → 3-Benzenesulphonyl-7-(4-methyl-piperazin-1-yl)-5-(4-methyl-piperazin-1-ylmethyl)-2-methylsulphanyl-pyrazolo[1,5-a]pyrimidine

Participants

Reaction Steps

0.4 g (4 mmol) of 1-methyl-piperazine was added to a solution of 0.8 g (1.77 mmol) of 3-benzenesulphonyl-7-chloro-5-(4-methyl-piperazin-1-ylmethyl)-2-methylsulphanyl-pyrazolo[1,5-a]pyrimidine in 20 ml of DMF and stirred at RT for 6 hrs. The reaction solution was evaporated and the residue was partitioned between 2N NaOH and CH2Cl2. The aqueous phase was extracted three times with CH2Cl2, and the combined organic phases were dried (MgSO4), filtered and evaporated. Subsequent chromatography (SiO2, CH2Cl2/MeOH/NH4OH 80:10:1) and crystallization from EtOH yielded 0.75 g (82%) of 3-benzenesulphonyl-7-(4-methyl-piperazin-1-yl)-5-(4-methyl-piperazin-1-ylmethyl)-2-methylsulphanyl-pyrazolo[1,5-a]pyrimidine as colorless crystals, m.p. 193-195°.

Provenance & Evidence