CAS No 79-33-4 , L(+)-Lactic acid

Title: L-Lactic Acid
CAS Registry Number: 79-33-4
CAS Name: (2S)-2-Hydroxypropanoic acid
Synonyms: L(+)-lactic acid; dextrorotatory lactic acid; d-lactic acid; sarcolactic acid; paralactic acid; Fleishmilchs?ure; L-Milchs?ure
Molecular Formula: C3H6O3
Molecular Weight: 90.08
Percent Composition: C 40.00%, H 6.71%, O 53.28%
Literature References: Occurs in small quantities in the blood and muscle fluid of man and animals. The lactic acid concn increases in muscle and blood after vigorous activity. L(+)-Lactic acid is also present in liver, kidney, thymus gland, human amniotic fluid, and other organs and body fluids. Obtained by resolution of DL-lactic acid: Purdie, Walker, J. Chem. Soc. 61, 754 (1892); Borsook et al., J. Biol. Chem. 102, 449 (1933). Convenient laboratory prepn from glucose by fermentation by Lactobacillus delbrueckii: Brin, Biochem. Prep. 3, 61 (1953). Prepn from hexoses using B. dextrolacticus: Andersen, Greaves, Ind. Eng. Chem. 34, 1522 (1942). Monograph: M. Brin, R. H. Dunlop, "Chemistry and Metabolism of L- and D-Lactic Acids" in Ann. N.Y. Acad. Sci. 119, 851-1165 (1965).
Properties: Crystals from acetic acid or chloroform, mp 53°. [a]546.121-22 +2.6° (c = 2.5). pK at 25°, 3.79. Forms salts with many metals. The salts are more sol in water than the salts of the racemic acid. Most of the salts are levoratory.
Melting point: mp 53°
pKa: pK at 25°, 3.79
Optical Rotation: [a]546.121-22 +2.6° (c = 2.5)
 
Derivative Type: Zinc L(-)-lactate dihydrate
Molecular Formula: Zn(C3H5O3)2.2H2O
Molecular Weight: 279.58
Percent Composition: Zn 23.40%, C 25.78%, H 5.05%, O 45.78%
Properties: Prisms. [a]D25 -8.2° (c = 2.5 in water).
Optical Rotation: [a]D25 -8.2° (c = 2.5 in water)