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ChemicalBook CAS DataBase List L-Malic acid
97-67-6

L-Malic acid synthesis

10synthesis methods
By hydration of maleic acid; by fermentation from sugars.
-

Yield:-

Reaction Conditions:

Stage #1: largazolewith ozone in dichloromethane at 25; for 0.5 h;
Stage #2: with formic acid;dihydrogen peroxide at 70; for 0.333333 h;
Stage #3: with hydrogenchloride;water at 110; for 24 h;

Steps:

3

Example 3: Determination of Absolute Configuration. A sample of compound 21 (~100 μg) was dissolved in 4 mL Of CH2Cl2 and subjected to ozonolysis at room temperature for 30 min. The solvent was evaporated and the residue was treated with 0.6 mL Of H2O2-HCO2H (1 :2) at 70 0C for 20 min. The solvent was evaporated and the resulting oxidation product was hydrolyzed with 0.5 mL of 6 N HCl at 1 10 0C for 24 h. The hydrolyzed product was dried and analyzed by chiral HPLC (column, Phenomenex Chirex phase 3126 N.S-dioctyl-φ)- pencillamine, 4.60 x 250 mm, 5 μm; solvent 1, 2 mM CuSO4 in 95:5 H2O/MeCν, pH 4.50; solvent 2, 0.5 mM Cu(OAc)2/0.1 M NH4OAc in 85:15 H2O/MeCN, pH 4.6; flow rate 1.0 mL/min; detection at 254 nm). The absolute configuration of the amino acids in the hydrolyzate was determined by direct comparison with the retention times of authentic standards. The retention times (tR, min) for solvent 1 were as follows: GIy (5.3), L-VaI (12.6), D-VaI (16.4), (S)-2-Me-cysteic acid (20.0), and (λ)-2-Me- cysteic acid (23.9). The retention times (JR, min) of the hydrolyzate components were 5.3, 12.6, 23.9, indicating the presence of GIy, L-VaI and (/?)-2-Me-cysteic acid in the product mixture. Solvent 2 was used to detect malic acid. Standard L-malic acid eluted at f? 7.6 min and D-malic acid at tR 20.4 min. Malic acid in the hydrolyzate eluted after 7.6 min, indicating the presence of the L isomer. GIy, L-VaI, and (R)-2- Me-cysteic acid eluted after 4.0, 5.8 and 6.5 min, respectively.

References:

WO2009/105284,2009,A1 Location in patent:Page/Page column 24-25

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