The reaction of 5-(chlorosulfonyl)-2-propoxybenzoic acid (I) with 2-(1-methylpyrrolidin-2-yl)ethylamine (II) in acetone gives the sulfonamide (III), which is treated with 2,4,6-trichlorobenzozyl chloride (IV) and TEA to afford the active mixed anhydride (V). The condensation of (V) with 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide (VI) in dichloromethane provides the corresponding carboxamide (VII). Finally, this compound is cyclized by means of tBu-OK in refluxing tert-butanol to furnish the target pyrrolo-pyrimidinone.

The reaction of 2-propoxybenzoic acid (I) with SOCl2 in refluxing dichloromethane gives the acyl chloride (II), which is condensed with 4-amino-1-methyl-3-propyl-1H-pyrazole-5-carboxamide (III) by means of TEA and DMAP in dichloromethane to yield the carboxamide (IV). The sulfonation of (IV) with chlorosulfonic acid affords the benzenesulfonyl chloride (V), which is treated with 2-(1-methylpyrrolidin-2-yl)ethylamine (VI) in dichloromethane to afford the sulfonamide (VII). Finally, this compound is cyclized by means of tBu-OK in refluxing tert-butanol to provide the target pyrazolo-pyrimidininone.