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    ChemicalBook CAS DataBase List D-PANTOTHENIC ACID
    79-83-4

    D-PANTOTHENIC ACID synthesis

    4synthesis methods
    -

    Yield:79-83-4 95.11%

    Reaction Conditions:

    with oxalic acid in water at 20; for 2 h;

    Steps:

    3.1 Step 1: Synthesis of (R)-3-(2,4-dihydroxy-3,3-dimethylbutanamido) propanoic acid (Pantothenic acid)
    To a mixture of calcium 3-[(2/?)-2,4-dihydroxy-3,3-dimethylbutanamido] propanoate (40.0 g, 83.9 mmol) in H2O (150 ml.) was added the solution of oxalic acid (7.55 g, 83.9 mmol) in H2O (100 mL), then the mixture was stirred at 20°C for 2 hours. The mixture was filtered through Celite, and eluted with H2O (30 mL), then the mixture was extracted by EtOAc (200 mL x 10), dried over Na?.S04, filtered and concentrated to give the title compound (i?)-3-(2,4-dihydroxy-3,3- dimethylbutanamido)propanoic acid (35 g, 95.11% ) as a colorless oil, which was used in the next step directly without further purification. (4132) [3256] ' NMR (400 MHz, DMSO-rfe): 6 0.78 (s, 3H), 0.80 (s, 3 I I). 2.40 (t, J= 7.2 Hz, 2H), 3.10-3.35 (m, 41 1). 3.70 (d, J= 5.2 Hz, I l f ). 4.46 (t, J= 5.2 Hz, 1H), 5.38 (d, J= 5.2 Hz, H I). 7.71 (t, ./ 6.0 Hz, IH), 12.23 (s, IH).

    References:

    COMET THERAPEUTICS, INC.;TAVERAS, Arthur George;SEKIRNIK, Angelina Roberta;KUSCER, Enej WO2020/198573, 2020, A1 Location in patent:Paragraph 3255-3256

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