Water → 8-Amino-1,3-di(cylcopropylmethyl)-7-(isopropylsulphonyl)xanthine

Sodium hydride (0.35 g of a 60% suspension in oil, 8.7 mmol) was added to a suspension of 8-amino-1,3-di(cyclopropylmethyl)xanthine (2 g, 7.3 mmol ) in dimethoxyethane (40 ml) and the resulting mixture stirred at ambient temperature for 2 hr. Isopropylsulphonyl chloride (1.24 g, 8.7 mmol) was added and the mixture was heated at reflux for 18 hours. The reaction mixture was allowed to cool and then water (1 ml) was added dropwise. The mixture was added to ethyl acetate (200 ml), washed with water (50 ml) and dried (MgSO4). The solvent was removed at reduced pressure to afford the crude residue which was chromatographed on silica (acetone/hexane 1:3) to afford 8-amino-1,3-di(cylcopropylmethyl )-7-(isopropylsulphonyl)xanthine (1.25 g, 45%) as a yellow foam. Recrystallisation from ethyl acetate/hexane afforded a white flocculent solid, m.p. 119°-120° C.

1. temperaturethe mixture was heated
2. temperatureat reflux for 18 hours
3. temperatureto cool
4. washwashed with water (50 ml)
5. dry with materialdried (MgSO4)
6. customThe solvent was removed at reduced pressure
7. customto afford the crude residue which
8. customwas chromatographed on silica (acetone/hexane 1:3)

ORD record

ord-269d794e01b44c05aeb7f76d416cde36

Source dataset

uspto-grants-1995_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05409934