What Are the Medical Uses of Mandelic Acid?

Mandelic acid, also known as bitter almond acid, is a white orthorhombic sheet-like crystal. Melting point is 119 ° C. Soluble in hot water, ether and isopropyl alcohol, insoluble in ethanol. Excessive exposure will cause discoloration and decomposition. By benzaldehyde and dibromoacetophenone action and prepared. For organic synthesis, it is a special reagent for the determination of zirconium.

Chinese name Mandelic acid

Chinese alias: bitter almond acid

English name: Mandelic acid

English alias: Amygdalic Acid; (±) --Hydroxyphenylacetic acid

CAS number: 90-64-2

Molecular formula: C ₈ H ₈ O ₃

Linear molecular formula: C6H5CH (OH) COOH

Molecular weight: 152.15

MDL number: MFCD00064250

Beilstein: 510011

EC number: 202-007-6

1. Properties: white orthorhombic flake crystals

2. Density (g / cm ³ ): 1.30

3. Melting point (° C): 119

4. Boiling point (° C, normal pressure): 321.8

5. Flash point (): 162.6

6. Specific rotation ( = 1, WATER): + 156.57 °

7. Solubility: easily soluble in water, ethanol, ether, isopropanol. ^[1]

1. Molar refractive index: 38.90

2. Molar volume (cm ³ / mol): 115.1

3. Isometric Zhang Rong (90.2K): 321.0

4. Surface tension (dyne / cm): 60.4

5. Polarizability (10 ^-24 cm ³ ): 15.42 ^[1]

1. Reference value for calculation of hydrophobic parameters (XlogP): None

2. Number of hydrogen-bonded donors: 2

3. Number of hydrogen bond acceptors: 3

4. Number of rotatable chemical bonds: 2

5. Number of tautomers: none

6. Topological molecular polar surface area: 57.5

7. Number of heavy atoms: 11

8. Surface charge: 0

9. Complexity: 138

10. Number of isotope atoms: 0

11. Determine the number of atomic stereocenters: 0

12. Uncertain number of atomic stereocenters: 1

13. Determine the number of chemical bond stereocenters: 0

14. Uncertain number of chemical bond stereocenters: 0

15. Number of covalent bond units: 1 ^[1]

There are three synthesis methods:

1) Benzaldehyde phase transfer method: Under the action of a quaternary ammonium salt phase transfer catalyst, benzaldehyde is sequentially added with chloroform and 50% aqueous sodium hydroxide solution. After the heating reaction, it is cooled, stirred, separated, sulfuric acid, and ethyl acetate Three extractions to obtain the product;

2) Acetophenone method: Acetophenone is reacted with nitrobenzene under the action of a base catalyst. Acetophenone, nitrobenzene and sodium hydroxide are reacted at a reaction temperature of 160-170 ° C under stirring for about 4 hours, the product is separated, the aqueous solution is acidified, and ether is extracted, and the benzene is recrystallized to obtain the product;

3) Benzene-glyoxylic acid method: 50% glycolic acid, benzene, and acetic acid are added dropwise with stirring. After the reaction at 80 ° C, the benzene layer and the water layer are separated, and a 5% sodium hydroxide aqueous solution is added to the benzene layer. The pH of the separated aqueous layer was set to 8. After the benzene layer and the aqueous layer were separated, 50% sulfuric acid was added to the aqueous layer so that the pH reached 5, and a precipitate was deposited. Filtrate, concentrate the filtrate, add 50% sulfuric acid to reach pH 1, filter the precipitate, wash with water, and dry to obtain the product.

In the pharmaceutical industry, it can be used as intermediates of ceftriazole, vasodilator cyclomandelate, eye drops oxybenzazole, pimoline, etc., and can also be used as a preservative. ^[1]

This product should be stored tightly. Packed in 25kg cardboard drums; during transportation, it must be protected from humidity, heat and sunlight; stored in a cool, dry, ventilated place, and away from fire and heat sources. ^[1]