摘要:
The catalytic hydrogenation of 3,6-bis(benzyloxycarbonylaminomethyl)-5-methyl-1,2-dihydropyrazin-2-one to remove benzyloxycarbonyl (Z) groups resulted ill a side reaction. Purification by reverse-phase HPLC and analysis by proton unclear magnetic resonance (H-1 NMR) spectroscopy identified the product as 3-aminomethyl-5,6-dimethyl-1,2-dihydropyrazin-2-one. It was determined through the synthesis of two 1,2-dihydropyrazin-2-one derivatives, composed of alanine and 2,3-diaminopropionic acid that deamination occurred specifically and easily (under atmospheric pressure and at the room temperature) Only in the case of 6-benzyloxycarbonylaminomethyl-3,5-dimethyl-1,2-dihydropyrazin-2-one. The catalytic hydrogenation of 3,6-bis(benzyloxycarbonylaminomethyl)-5-methyl-1,2-dihydropyrazin-2-one specifically yields the deaminated product, 3-aminomethyl-5,6-dimethyl-1,2-dihydropyrazin-2-one. (C) 2002 Elsevier Science Ltd. All rights reserved.