Sodium Hydroxide → HCID 15462258, compound

Participants

Reaction Steps

3.59 g of 3-(3-cyclopentyloxy-4-methoxy-benzyl)-8-isopropyl-xanthine and 2.40 g of phosphorus pentasulfide were heated under reflux in 60 ml of pyridine for 8 hours. At -5° C., 11.9 ml of 2N NaOH were added slowly. The suspension was evaporated to dryness, the residue suspended in 100 ml of water, neutralized to pH 8, and the solid, collected, washed and dried to give the crude 6-thioxanthine (3.45 g). Purification by filtration chromatography (SiO2, 15 g; chloroform) yielded a solid which was reprecipitated from NaOH by addition of HCl, to pH 6.5, collected, washed and dried to give the monohydrate of the title compound (3.38 g) as a white solid, mp 192-3° C.

Provenance & Evidence