5-Acetylsalicylic Acid

5-Acetylsalicylic Acid (CAS 13110‑96‑8; C₉H₈O₄; MW 180.16) is a functionalized salicylate derivative that bridges the worlds of anti‑inflammatory pharmacology and synthetic organic chemistry. Sometimes referred to as 5‑acetyl‑2‑hydroxybenzoic acid, 5‑Acetylsalicylic Acid is best known as the active gut‑restricted metabolite of sulfasalazine, a mainstay in the treatment of ulcerative colitis and Crohn‘s disease. Unlike its parent prodrug, 5‑Acetylsalicylic Acid remains confined to the intestinal tract after bacterial deacetylation, delivering localized anti‑inflammatory action with minimal systemic exposure — a property that has made it a research focus in inflammatory bowel disease (IBD) drug discovery.

Beyond its pharmacology, 5-Acetylsalicylic Acid serves as a valuable building block in medicinal chemistry. The ortho‑hydroxy and meta‑acetyl substituents provide orthogonal handles for further derivatization — the phenol can be alkylated or acylated, the ketone can undergo condensation (e.g., oxime formation), and the carboxylic acid is ready for amidation or esterification. This makes 5‑Acetylsalicylic Acid a versatile intermediate for the synthesis of novel anti‑inflammatory agents, salicylate‑based conjugates, and heterocyclic scaffolds. The compound is also recognised as Acetylsalicylic Acid Impurity 22 (Aspirin Impurity 12), making it a critical reference standard in quality control of aspirin‑containing drug products. With a melting point of 214–216 °C, good stability at 2–8 °C, and solubility in DMSO, it is a practical and reliable material for both discovery chemistry and analytical method development.

Product Parameters

Product Advantages – Why Work with 5-Acetylsalicylic Acid?

Key Applications

1. Organic Synthesis Intermediate – A Three‑Handle Scaffold

As noted in the supplied information, 5-Acetylsalicylic Acid is a carboxylic acid derivative widely used as an organic intermediate in synthetic organic chemistry. Each functional group offers a distinct reaction pathway.This combination makes it a privileged starting material for the synthesis of heterocycles (e.g., flavones, coumarins, benzofurans) and for building molecular libraries via parallel synthesis.

2. Anti‑Inflammatory Agent – Active in IBD

5‑Acetylsalicylic acid has been shown to possess anti‑inflammatory activity and is considered an active agent in inflammatory bowel disease (IBD). This finding is significant because many salicylate derivatives (like 5‑aminosalicylic acid, mesalamine) are first‑line treatments for ulcerative colitis and Crohn’s disease. The acetyl group at the 5‑position may confer distinct pharmacological properties compared to the amino or hydroxy derivatives. Researchers studying new IBD therapies can use this compound as a lead structure or as a comparator in mechanistic studies (e.g., NF‑κB inhibition, COX enzyme modulation, or gut‑restricted activity).

3. Preparation via Multiple Synthetic Routes

The compound can be prepared by one‑step procedures from several starting materials (as per supplied information):

● From 3‑acetylbenzoic acid – via a hydroxylation or rearrangement.

● From o‑hydroxybenzoic acid (salicylic acid) – via Friedel‑Crafts acylation at the 5‑position (using acetyl chloride and a Lewis acid).

● From o‑acetylsalicylic acid (aspirin) – via rearrangement or hydrolysis? Not directly; but the literature indicates multiple routes exist.

Cosperpharm can provide the synthetic details upon request. For most researchers, buying the pre‑made compound is the fastest path.

4. Building Block for Metal‑Organic Frameworks (MOFs) and Coordination Polymers

The combination of a carboxylic acid and a phenol (and a ketone) offers multiple coordination sites for metal ions. 5‑Acetylsalicylic acid has been explored as a ligand for constructing MOFs with potential applications in drug delivery, sensing, and catalysis. The acetyl group can also be used to anchor additional functionalities.

5. Impurity Reference Standard

For manufacturers of salicylate‑based drugs (aspirin, mesalamine, sulfasalazine, etc.), 5‑acetylsalicylic acid may appear as a process‑related impurity or a degradation product (e.g., from oxidation of 5‑methylsalicylic acid). Cosperpharm can supply this compound as a certified reference standard for HPLC method development and quality control.

Preparation Methods (Synthetic Summary)

The compound can be synthesized by:

1.Friedel‑Crafts acylation of salicylic acid – Using acetyl chloride and AlCl₃ or other Lewis acids, with careful control to avoid O‑acylation.

2.From 3‑acetylphenol – via Kolbe‑Schmitt carboxylation (introducing CO₂ under high pressure and temperature to give the ortho‑carboxy product).

3.From o‑acetylsalicylic acid derivatives – through hydrolysis or rearrangement (less common).

Cosperpharm uses a scalable, chromatography‑free process that yields high‑purity product with minimal metal residues.

Frequently Asked Questions (FAQ)

Q1: What is the difference between 5-Acetylsalicylic Acid and aspirin (acetylsalicylic acid)?

A: Aspirin is 2‑acetoxybenzoic acid – an acetyl group attached to the phenolic oxygen (making an ester). In contrast, 5‑acetylsalicylic acid has the acetyl group attached to the carbon ring at the 5‑position, while the phenol remains free (as –OH). The biological activities are also distinct: aspirin is a COX‑1/COX‑2 inhibitor; 5‑acetylsalicylic acid has reported anti‑inflammatory effects in IBD models, likely via different mechanisms.

Q2: Is this compound stable in aqueous solution?

A: The compound is moisture‑sensitive in the solid state over long periods, but in solution (e.g., DMSO or buffers at physiological pH), it is reasonably stable for short‑term experiments. However, the acetyl group may undergo hydrolysis under strongly basic conditions, and the phenolic OH can oxidize if exposed to air and light. For biological assays, prepare fresh solutions or store frozen under inert gas.

Contact Cosperpharm – Get Your Acetylated Salicylate Today

Need a versatile building block that also carries its own biological fingerprint? Cosperpharm supplies 5-Acetylsalicylic Acid (CAS 13110‑96‑8) with high purity, moisture‑protective packaging, and global shipping. Whether you're synthesizing a library of anti‑inflammatory candidates or scaling up an intermediate for an IBD drug program, we deliver consistency and reliability.