Chemical and physical properties of pantothenic acid or vitamin B5

1. Chemical and physical
properties of pantothenic acid
Domina Petric, MD

2. Essential features of the chemical
structure:
Formal derivative of
pantoic acid and alanine
Optically active
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
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3. Panthenol is a provitamin.
Comptox.epa.gov
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
3

4. Pantothenic acid or B5
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
4
Studyandexam.com

5. Nomenclature
• Pantothenic acid is the trivial designation for
the compound
dihydroxy-β,β-dimethylbutyryl-β-alanine.
It has two metabolically active forms:
• coenzyme A, in which the vitamin is linked
via a phosphodiester group with adenosine-
3′,5′-diphosphate
• acyl-carrier protein, in which it is linked
via a phosphodiester to a serinyl residue of
the protein
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
5

6. Chemical and physical properties
• Pantothenic acid is composed of
β-alanine joined to 2,4-dihydroxy-
3,3-dimethylbutyric acid via an amide
linkage.
• The molecule has an asymmetric center
and only the R-enantiomer, usually called
D-(+)pantothenic acid, biologically active
and occurs naturally.
• Pantothenic acid is a yellow, viscous oil.
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
6

7. Chemical and physical properties
Its calcium and other salts are colorless
crystalline substances.
Calcium pantothenate is the main product
of commerce.
Neither form is soluble in organic solvents,
but each is soluble in water and ethanol.
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
7

8. Chemical and physical properties
• Aqueous solutions of
pantothenic acid are unstable to
heating under acidic or alkaline
conditions, resulting in the
hydrolytic cleavage of the
molecule to yield β-alanine and
2,4-dihydroxy-3,3-
dimethylbutyrate.
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
8

9. Chemical and physical properties
The analog panthenol (in which
the carboxyl group is replaced
by an hydroxymethyl group) is
fairly stable in solution.
In dry form, the salts are stable
to air and light, but they
(particularly sodium
pantothenate) are hygroscopic.
April 17, 2018
Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
9

10. Literature
• Combs GF. The Vitamins. Fundamental Aspects in
Nutrition and Health. Elsevier Inc. 2008.
April 17, 2018 10