1: 81 percent / dimethylformamide / 2 h / 90 °C 2: methylhydrazine / ethanol / 2 h / Heating 3: EtONa / ethanol / 1 h / Heating 4: 97 percent / 0.65 M HCl / Ambient temperature 5: 91 percent / DCC, pyridine, DMAP / CH2Cl2 / 64 h / Ambient temperature 6: 75 percent / LiBH4, LiEt3BH / tetrahydrofuran / Ambient temperature 7: 66 percent / DAST / CH2Cl2 / 60 h / Ambient temperature 8: phosphate buffer / Ambient temperature; immobilized penicillin-G amidase View Scheme

1: 97 percent / 0.65 M HCl / Ambient temperature 2: 91 percent / DCC, pyridine, DMAP / CH2Cl2 / 64 h / Ambient temperature 3: 75 percent / LiBH4, LiEt3BH / tetrahydrofuran / Ambient temperature 4: 66 percent / DAST / CH2Cl2 / 60 h / Ambient temperature 5: phosphate buffer / Ambient temperature; immobilized penicillin-G amidase View Scheme