Diethylamine → (3S)-3-amino-4-oxobutyric acid tert-butyl ester semicarbazone

HRID 363874Notes

Reaction equation

HRID 363874 reaction equation
[C:1]([O:5][C:6](=[N:29][NH:30][C:31]([NH2:33])=[O:32])[CH2:7][C@H:8]([NH:11]C(OCC1C2CC3C(=CC=CC=3)C=2C=CC=1)=O)[CH:9]=[O:10])([CH3:4])([CH3:3])[CH3:2].C(NCC)C>CN(C=O)C>[C:1]([O:5][C:6](=[N:29][NH:30][C:31]([NH2:33])=[O:32])[CH2:7][C@H:8]([NH2:11])[CH:9]=[O:10])([CH3:4])([CH3:2])[CH3:3]

Participants

4

Reactant 2

HCID 8021DiethylamineHCID 566185953(S)-(1-fluorenylmethyloxycarbonylamino)-4-oxobutyric acid tert-butyl ester semicarbazone

Product 1

HCID 53985399(3S)-3-amino-4-oxobutyric acid tert-butyl ester semicarbazone

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

(3S)-3-(1-Fluorenylmethyloxycarbonylamino)-4-oxobutyric acid tert-butyl ester semicarbazone (210 mg, 0.45 mol, Prepared in a similar manner to the benzyloxycarbonyl analog in Graybill et al., Int. J. Protein Res., 44, pp. 173-82 (1994).) was dissolved in 10 ml of DMF and 2 ml of diethylamine and stirred for 2 h. The reaction was concentrated in vacuo to give (3S)-3-amino-4-oxobutyric acid tert-butyl ester semicarbazone. The 0° C. solution of the above residue and 603a (200 mg, 0.42 mmol) in 5 ml of DMF and 5 ml of CH2Cl2 was treated with 1-hydroxybenzotriazole (57 mg, 0.42 mmol) and 1-(3-dimethylaminopropyl)-3ethylcarbodiimide hydrochloride (98 mg, 0.51 mmol). The reaction was stirred at RT for 18 h, poured onto EtOAc (75 ml) and washed with aq. 0.3N KHSO4, sat. aq. NaHCO3 and sat. aq. NaCl, dried over NaSO4 and concentrated in vacuo. Chromatography (flash, SiO2, 0% to 4% MeOH/0.1% NH4OH/CH2Cl2) to give 240 mg (83%) of 604a.

Workup

  1. concentrationThe reaction was concentrated in vacuo

Sources & evidence

ORD record
ord-ee0c59d28bdf40d3bdbf382de27b8c9a
Source dataset
uspto-grants-1999_02
Patent number
US05874424

Reaction notes

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