6-[1-(4-chlorophenyl)-cyclopentylmethyl]-9-hydroxy-2-isopropyl-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione → 9-hydroxy-2-isopropyl-6-(1-phenyl-cyclopentylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione
Reaction equation
Cl[C:2]1[CH:7]=[CH:6][C:5]([C:8]2([CH2:13][C:14]3[N:19]4[CH2:20][CH2:21][N:22]([CH:25]([CH3:27])[CH3:26])[C:23](=[O:24])[C:18]4=[C:17]([OH:28])[C:16](=[O:29])[N:15]=3)[CH2:12][CH2:11][CH2:10][CH2:9]2)=[CH:4][CH:3]=1>[Pd]>[OH:28][C:17]1[C:16](=[O:29])[N:15]=[C:14]([CH2:13][C:8]2([C:5]3[CH:4]=[CH:3][CH:2]=[CH:7][CH:6]=3)[CH2:9][CH2:10][CH2:11][CH2:12]2)[N:19]2[CH2:20][CH2:21][N:22]([CH:25]([CH3:27])[CH3:26])[C:23](=[O:24])[C:18]=12Participants
3
Reactant 1
Product 1
Reagents, catalysts & solvents 1
Procedure
To a stirred solution of 6-[1-(4-chlorophenyl)-cyclopentylmethyl]-9-hydroxy-2-isopropyl-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (32-03) (350 mg, 0.842 mmol) was added 35 mg 10% Pd—C. Hydrogenation was conducted by balloon pressure at room temperature for 9 h. After completion of the reaction, the mixture was filtered over a celite bed, which was washed with methanol, followed by 10% methanol in dichloromethane. The filtrate was concentrated to a pasty mass, which was washed with ether, followed by pentane to get 9-hydroxy-2-isopropyl-6-(1-phenyl-cyclopentylmethyl)-3,4-dihydro-2H-pyrazino[1,2-c]pyrimidine-1,8-dione (32-04) (175 mg, 54.5%) as a yellow solid.