| Product Name | Esomeprazole |
|---|---|
| CAS Number | 119141-88-7 |
| Molecular Formula | C17H19N3O3S |
| Molecular Weight | 345.42 |
| Appearance | White to off-white crystalline powder |
| Assay (HPLC) | ≥ 99.0% |
| Loss on Drying | ≤ 0.5% |
| Residue on Ignition | ≤ 0.1% |
| Heavy Metals | ≤ 10 ppm |
| Melting Point | 155°C - 160°C |
| Specific Rotation | −150° to −160° (c=1, methanol) |
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Synonyms
Esomeprazole, Nexium, Esomeprazole base, (S)-Omeprazole, Esomeprazole anhydrous, Esomeprazole EP, Esomeprazole USP, (S)-5-Methoxy-2-[[(4-methoxy-3,5-dimethyl-2-pyridinyl)methyl]sulfinyl]-1H-benzimidazole
Esomeprazole is the S-isomer of omeprazole, and it’s the one that actually does the heavy lifting when it comes to acid suppression. It’s the active ingredient in Nexium, one of the best-selling proton pump inhibitors in the world. By selectively inhibiting the H+/K+-ATPase enzyme system in gastric parietal cells, it blocks acid secretion at the final step — which means it works faster and lasts longer than many other PPIs. For manufacturers, that translates into a reliable, well-documented API for treating GERD, peptic ulcers, and H. pylori eradication regimens. We supply esomeprazole as a high-purity crystalline powder, every batch shipped with a full COA, flexible from 1 kg trial runs to bulk container orders, and ready for worldwide delivery.