反应详情

In accordance with this process, 6-Chlorouracil (1) is alkylated with 2-(bromomethyl)benzonitrile in the presence of NaH and LiBr in a mixture of DMF-DMSO to produce the N-benzyluracil derivative (2) in 54% yield. Compound (2) is further alkylated with iodomethane and NaH in DMF/THF to give the 1,3 disubstituted uracil (3) in 72% yield. Subsequent displacement of chlorouracil (IV) with 3(R)-aminopiperidine dihydrochloride in the presence of either NaHCO3 in hot methanol or K2CO3 in aqueous isopropanol provides alogliptin (4), which is isolated as the corresponding benzoate salt by treatment with benzoic acid in ethanol. The overall yield of this three-stage process is ˜20-25%. One of the disadvantages of above described process is the difficulty to separate and purify mixtures of solvents with high boiling point (for example, DMF/DMSO) for recycling. Another disadvantage is the usage of hazardous materials such as sodium hydride, which requires anhydrous solvents as a reaction media.