8-Isobutyryloxy-5-methyl-6-oxo-5,6-dihydro-pyrido[2,3-b]pyrazine-7-carboxylic acid methyl ester → 8-hydroxy-5-methyl-7-(3-methyl-1,2,4-oxadiazol-5-yl)-5H-pyrido[2,3-b]pyrazin-6-one

Participants

Reaction Steps

To a solution of 8-isobutyryloxy-5-methyl-6-oxo-5,6-dihydro-pyrido[2,3-b]pyrazine-7-carboxylic acid methyl ester (Example 7.3) (0.10 g) in toluene (4 ml) was added N-hydroxy-acetamidine (0.025 g). The reaction mixture was heated to reflux for 16 hours. The reaction mixture was cooled to ambient temperature and the solid was isolated by filtration and dried to give Compound No. B5 of Table 5 (0.050 g).

Provenance & Evidence