L(+)-Ascorbic acid
[CAS 50-81-7]

Identification

• Classification: API >> Vitamins and minerals >> Vitamin C drugs
• Name: L(+)-Ascorbic acid
• Synonyms: L-Ascorbic acid; Vitamin C; L-Threo-2,3,4,5,6-pentahydroxy-1-hexenoic acid-4-lactone
• Molecular Formula: C₆H₈O₆
• Molecular Weight: 176.12
• CAS Registry Number: 50-81-7
• EC Number: 200-066-2
• SMILES: C([C@@H]([C@@H]1C(=C(C(=O)O1)O)O)O)O

Properties

• Density: 2.0±0.1 g/cm³ Calc.^*, 1.65 g/mL (Expl.)
• Melting point: 190 - 194 °C (Decomposes) (Expl.)
• Boiling point: 552.7±50.0 °C 760 mmHg (Calc.)^*
• Flash point: 238.2±23.6 °C (Calc.)^*
• Solubility: water: 333 g/L (20 °C) (Expl.)
• Index of refraction: 1.711 (Calc.)^*
• Alpha: 20.5 ° (c=10,H2O) (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H319
• Safety Statements: P264-P280-P305+P351+P338-P337+P313

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Serious eye damage	Eye Dam.	1	H318
Eye irritation	Eye Irrit.	2A	H319
Skin corrosion	Skin Corr.	1	H314

chemBlink Chemical Story

L(+)-Ascorbic acid is vitamin C, a six-carbon water-soluble vitamin whose history links scurvy, nutritional science, structural chemistry, and industrial synthesis. Albert Szent-Gyorgyi isolated 'hexuronic acid' from biological materials in the late 1920s; work by Svirbely, Szent-Gyorgyi, King, and others established its identity with the antiscorbutic factor in 1932. Norman Haworth and collaborators established its constitution in 1933, and the name ascorbic acid reflected its action against scurvy. Humans cannot synthesize sufficient vitamin C and must obtain it from diet. Chemically, its enediol system is readily oxidized, making ascorbate an important reducing agent. Biologically, vitamin C is also an enzyme cofactor, including in collagen hydroxylation. Industrial synthesis historically followed the Reichstein process and later fermentation-based improvements.

Exact chemical identity matters because free forms, salts, stereoisomers, hydrates, metabolites, intermediates, and finished products can carry different registry numbers even when their names are closely related. These distinctions affect molecular weight, physical properties, analytical standards, formulation, and interpretation of literature. A reliable chemical database therefore follows the exact substance instead of automatically transferring every property of a related form.

Functional groups are also a map of intended reactivity. Carbonyls, alcohols, amines, halides, alkenes, and heterocycles provide different opportunities for bond formation, while hydrocarbon frameworks influence shape and solubility. In multistep synthesis, the usefulness of an intermediate often comes from being able to transform one position selectively while leaving another group available for a later operation.

Modern chemical development depends as much on characterization as on synthesis. Identity, purity, stereochemistry, water or salt content, and process-related impurities may all need control. Well-characterized intermediates and reference materials therefore matter even when they never become a final commercial product: they make complex manufacturing and research reproducible.

A responsible Chemical Story distinguishes documented use from structural possibility. A familiar molecular scaffold can suggest a hypothesis, but resemblance alone does not establish a biological target, approved indication, or commercial application. When exact-CAS literature is limited, verified chemistry and clearly documented uses are more informative than speculation.

Seen broadly, practical performance emerges from the whole molecular system. Structure, stereochemistry, physical form, synthetic route, reaction environment, and, for biological molecules, metabolism can all determine what a substance actually does. Connecting these details to a documented historical, industrial, or biological role turns a registry entry into a meaningful chemical story.

Exact chemical identity matters because free forms, salts, stereoisomers, hydrates, metabolites, intermediates, and finished products can carry different registry numbers even when their names are closely related. These distinctions affect molecular weight, physical properties, analytical standards, formulation, and interpretation of literature. A reliable chemical database therefore follows the exact substance instead of automatically transferring every property of a related form.

Functional groups are also a map of intended reactivity. Carbonyls, alcohols, amines, halides, alkenes, and heterocycles provide different opportunities for bond formation, while hydrocarbon frameworks influence shape and solubility. In multistep synthesis, the usefulness of an intermediate often comes from being able to transform one position selectively while leaving another group available for a later operation.

Modern chemical development depends as much on characterization as on synthesis. Identity, purity, stereochemistry, water or salt content, and process-related impurities may all need control. Well-characterized intermediates and reference materials therefore matter even when they never become a final commercial product: they make complex manufacturing and research reproducible.

References:
1. Carpenter KJ. The discovery of vitamin C. Ann Nutr Metab. 2012;61:259-264.
2. Svirbely JL, Szent-Gyorgyi A. The chemical nature of vitamin C. Biochem J. 1932;26:865-870.
3. Haworth and colleagues. Structural and synthetic studies of vitamin C, 1933-1934.

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