H-Thr(ac)-oh

• CAS: 17012-42-9
• Catalog Number: ACM17012429
• Category: Main Products
• Molecular Weight: 161.16
• Molecular Formula: C₆H₁₁NO₄
• Synonyms: O-ACETYL-L-THREONINE;H-THR(AC)-OH
• IUPAC Name: (2S,3R)-3-acetyloxy-2-aminobutanoicacid
• Canonical SMILES: CC(C(C(=O)O)N)OC(=O)C
• InChI Key: GOVSRIMJZNIFHS-WUJLRWPWSA-N
• Exact Mass: 161.06900

Case Study

O-Acetyl-L-Threonine Used for the Synthesis the Marfey Standard Compound of Threonine

Aurelio, Luigi, et al. Australian journal of chemistry, 2006, 59(6), 407-414.

Acetate ester protection of the side chain hydroxyl group enabled the preparation of Marfey standard 27 for threonine. The specific steps include:
· The synthesis of (2S,3R)-3-acetoxy-2-(benzyloxycarbonylamino)butanoic acid 22 started with the acetylation and carbamoylation of O-acetyl-l-threonine. Vigorously stirred 2.0 grams of finely powdered O-acetyl-l-threonine (12.4 mmol) in 30 milliliters of DMF. The produced heterogeneous solution received an addition of triethylamine (4.3 mL, 31.0 mmol) before compound 29 (3.1 g, 12.5 mmol) was introduced and stirring persisted at room temperature. The solution became homogeneous after one hour of stirring and was stirred for an additional two hours before solvent removal occurred under reduced pressure. After dissolving the residue in 150 mL of 1 M HCl, extracted the aqueous phase with three 50 mL portions of diethyl ether. Ethyl ether fractions underwent sequential washing with 50 mL of 1 M HCl followed by 50 mL of water and 50 mL of brine. The organic layer underwent drying with MgSO4 before being filtered and concentrated to produce an oil that transformed into a solid state. Recrystallized this solid from ether/hexane to produce 3.41 g of acid 22 with a 93% yield.
· The subsequent process generated oxazolidinone 23 with 91% yield before reductive cleavage with trifluoroacetic acid and triethylsilane led to obtaining N-methyl threonine 24 as its dicyclohexylammonium (DCHA) salt. The desired hydroxy acid 25 was successfully obtained with an 88% yield through acidic hydrolysis using 2 M hydrochloric acid in dioxane at 60°C for 35 hours. N-methyl l-threonine 26 resulted from the hydrogenolysis of carbamate 25 and further treatment with Marfey's reagent 17 produced the expected Marfey's standard 27 after an acidic work-up.