Calcium Pantothenate, Racemic

Calcium Pantothenate, Racemic, occurs as a white, slightly hygroscopic powder. It is a mixture of the calcium salts of the dextrorotatory (d) and levorotatory (dl) isomers of pantothenic acid. It is optically inactive. It is stable in air and freely soluble in water. It is soluble in glycerin, and is practically insoluble in alcohol, in chloroform, and in ether. Its solutions are neutral or alkaline to litmus. 

Calcium Gluconate, 60 Calcium Glycerophosphate, 60 Calcium Hydroxide, 61 Calcium Hydroxide TS, 850 Calcium Hydroxyapatite, 69, (Sl)10 Calcium Identification Test, 753 Calcium Iodate, 62 Calcium Lactate, 62 Calcium Lactobionate, 63 Calcium Lignosulfonate, (S 1)7 Calcium Oxide, 64 Calcium Pantothenate, 64 D-Calcium Pantothenate, 64 Calcium Pantothenate, Calcium Chloride Double Salt, 66 Calcium Pantothenate, Racemic, 65 Calcium Peroxide, 67 Calcium Phosphate, Dibasic, 67, (Sl)8 Calcium Phosphate, Monobasic, 68,... 

Calcium pantothenate, racemic. See Calcium DL-pantothenate Calcium paraben... 

The major producers of the calcium salt of pantothenic acid and panthenol are Hoffmann-La Roche, Daiichi, BASF, and Alps. Racemic panthenol is used mainly in hair care products, whereas (R)-panthenol is exclusively used in top-of-the-line, more expensive skin and hair care products. The current (ca 1997) price of (R,3)-panthenol varies between 12 and 18 per kg, that of D-panthenol varies between 30 and 45 per kg, and that of D-calcium pantothenate (Calpan) varies between 22 and 30 per kg. 

The development of a novel production system for D-pantoyl lactone (which is a lactone compound carrying a chiral hydroxy group and a chiral intermediate for the commercial production of D-pantothenate) by microbial asymmetric reduction has been undertaken. D-pantothenate is mainly used in various pharmaceutical products and as an animal feed additive, the current world production of calcium pantothenate being about 6,000 tons per year. Conventional commercial production of D-pantoyl lactone has depended exclusively on chemical synthesis involving optical resolution of a chemically synthesized racemic pantoyl lactone, which is the most troublesome step of the pantothenate synthesis process. 

Note The physiological activity of Racemic Calcium Pantothenate is approximately one-half that of the dextrorotatory isomer. 

The major industrial route to calcium pantothenate starts from isobutyralde-hyde, which is condensed with formaldehyde. Hydrocyanation and hydrolysis affords the racemic pantolactone (Fig. 8.20). The resolution of pantolactone is carried out by diastereomeric crystallization with a chiral amine, such as (+)-2-aminopinane (BASF), 2-benzylamino-l-phenylethanol (Fuji) or (lR)-3-endo-ami-nonorbomeol (Roche). The undesired enantiomer is racemized and recycled. 

Calcium Pantotothenate Racemic Calcium Pantothenate Method I USP (24, pp. 289 and 290)... 

Racemic Calcium Pantothenate, USP. Racemic calcium pantothenate provides a more economical source of this vitamin. Other than containing nut less than 45% of the dextrorotatory biologically active form, its properties are very similar to tho.se of calcium pantothenate. USP. 

R7557P. See Novolac resin R7559. See Phenolic resin RA-061. See EPM rubber Rabcide. See 4,5,6,7-Tetrachlorophthalide Racemethionine. See DL-Methionine Racemic calcium pantothenate. See Calcium DL-pantothenate... 

We found in our laboratory, a novel lactonohydrolase that catalyzes reversible hydrolysis of various lactones including aldonate lactones and aromatic lactones. The enzyme was crystallized from Fusarium oxysporum and characterized. It has been shown that the enzyme hydrolyzes only D-pantoyl lactone, a chiral intermediate for the commercial production of D-pantothenate, in a racemic mixture of pantoyl lactone and that the enzyme is very useful for the optical resolution of racemic pantoyl lactone (Fig. 3)7. When F. oxysporum mycelia entrapped in calcium alginate gel were incubated in 30% solution of DL-pantoyl lactone, almost stoichiometric hydrolysis of D-pantoyl lactone was observed. After repeated reactions for 150 times over 150 days, the mycelia retained more than 90% of their initial activity. A 1,000... 

Currently, (J )-pantothenic acid is industrially produced by conventional chemical synthesis and marketed as the calcium salt (calpan). The global market of calpan was valued at approximately 75 million US dollars in sales in 2005 with a world output over 10 000 ton. The key starting material for large-scale chemical processes is (J )-pantolactone. This molecule can be coupled with either calcium P-alanine to form (J )-pantothenate or with 3-aminopropanol to form panthenol, an important ingredient in skin and hair care consumer products. Purification of (7 )-pantolactone from racemic mixtures occurs by chemical or enzymatic racemic resolution [320, 321]. 

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