1.1: lithium aluminium tetrahydride / tetrahydrofuran / 2 h / |Reflux 2.1: sodium hydride / tetrahydrofuran; mineral oil / 8 h / |Reflux 2.2: 29 h / 20 °C 3.1: trifluoroacetic acid / dichloromethane View Scheme

1.1: LHMDS / tetrahydrofuran / 1 h / -78 °C 1.2: 73 percent / tetrahydrofuran / 2 h / -78 - -30 °C 2.1: 44 percent / 1N NaOH / Pseudomonas mendocina lipase / aq. phosphate buffer / 72 h / 4 °C / pH 7.0 / Enzymatic reaction 3.1: 93 percent / TFA / CH2Cl2; H2O / 2 h / 20 °C / Acid hydrolysis 4.1: 99 percent / LiOH / H2O / pH 10 5.1: 73 percent / pyridoxal phosphate; cysteine sulfinic acid / Glutamic Oxalacetic Transaminase (GOT) / H2O / 24 h / 20 °C / pH 7 / Enzymatic reaction View Scheme

1.1: LHMDS / tetrahydrofuran / 1 h / -78 °C 1.2: 73 percent / tetrahydrofuran / 2 h / -78 - -30 °C 2.1: 1N NaOH / Pseudomonas mendocina lipase / aq. phosphate buffer / 72 h / 4 °C / pH 7.0 / Enzymatic reaction 3.1: 100 percent / SOCl2 / Heating 4.1: 95 percent / TFA / CH2Cl2; H2O / 2 h / 20 °C / Acid hydrolysis 5.1: 98 percent / LiOH / H2O / pH 10 6.1: 78 percent / pyridoxal phosphate; cysteine sulfinic acid / Glutamic Oxalacetic Transaminase (GOT) / H2O / 24 h / 20 °C / pH 7 / Enzymatic reaction View Scheme

N,N,N',N',N'',N''-hexamethylphosphoric triamide; n-butyllithium; ammonium chloride; diisopropylamine in tetrahydrofuran