Dimethyl Sulfoxide → o-Fluoro-p-[N-((6RS)-2-methyl-4-oxo-3-pivaloyloxymethyl-3,4,7,8-tetrahydro-6H-cyclopenta[g]quinazolin-6-yl)amino]benzoic acid

Participants

Reaction Steps

A mixture of 6-bromo-2-methyl-3-pivaloyloxymethyl-3,4,7,8-tetrahydro-6H-cyclopenta[g]quinazolin-4-one (26 g), p-amino-o-fluorobenzoic acid 1,1-dimethyl-2-hydroxyethylammonium salt (42 g), calcium carbonate (21.4 g) and DMSO (200 ml) was stirred at ambient temperature for 72 hours. The mixture was poured onto a mixture of ice and water (1 liter). The precipitate was isolated, washed with water and dried under vacuum. The product was purified by column chromatography using initially a 9:1 mixture of methylene chloride and methanol and then a 9:1:0.1 mixture of methylene chloride, methanol and acetic acid as eluant. There was thus obtained o-fluoro-p-[N-((6RS)-2-methyl-4-oxo-3-pivaloyloxymethyl-3,4,7,8-tetrahydro-6H-cyclopenta[g]quinazolin-6-yl)amino]benzoic acid as a gum (20 g).

Provenance & Evidence