Zastaprazan is a synthetic small-molecule potassium-competitive acid blocker (P-CAB) developed for the treatment of acid-related gastrointestinal disorders. It is also known by the development code JP-1366 and is designed to inhibit the gastric H+/K+-ATPase proton pump, thereby reducing gastric acid secretion.
Zastaprazan has the molecular formula C22H26N4O, molecular weight approximately 362.47 g/mol, and CAS Registry Number 2133852-18-1. The compound is achiral and has no defined stereocenters. These chemical identifiers are confirmed by the FDA Global Substance Registration System and PubChem.
The systematic chemical name of Zastaprazan is azetidin-1-yl-[8-[(2,6-dimethylphenyl)methylamino]-2,3-dimethylimidazo[1,2-a]pyridin-6-yl]methanone.
Zastaprazan belongs to the imidazopyridine-derived P-CAB class. Unlike conventional proton pump inhibitors that require acid activation, P-CAB compounds directly and reversibly inhibit the gastric proton pump through potassium-competitive binding.
Zastaprazan is also identified by the synonyms JP-1366 and JP1366. IUPHAR/BPS identifies it as a synthetic organic compound and records its approval by the South Korean MFDS in 2024.
Zastaprazan acts on the gastric H+/K+-ATPase, the enzyme responsible for the final step of gastric hydrochloric acid secretion. By competitively inhibiting potassium binding to the proton pump, Zastaprazan suppresses gastric acid secretion.
Its pharmacological classification is potassium-competitive acid blocker (P-CAB). This mechanism makes Zastaprazan part of the newer generation of acid-suppressive pharmaceutical agents.
Zastaprazan has demonstrated potent inhibition of gastric proton pump activity in pharmacological studies. Published pharmaceutical research describes it as a potent and selective H+/K+-ATPase inhibitor.
Zastaprazan has been developed primarily for gastroesophageal reflux disease (GERD) and other acid-related gastrointestinal conditions.
IUPHAR/BPS records Zastaprazan as an approved drug in South Korea, while pharmaceutical databases report its use for erosive gastroesophageal reflux disease.
The compound has also been investigated in clinical development programs involving acid-related gastrointestinal disorders, including reflux esophagitis and peptic ulcer-related applications.
The commercial pharmaceutical development of Zastaprazan makes the API relevant to pharmaceutical research, formulation development and manufacturing programs involving P-CAB products.
Zastaprazan is a synthetic organic small molecule with a molecular formula of C22H26N4O and molecular weight of approximately 362.47 g/mol. FDA's Global Substance Registration System identifies the substance as achiral with no defined stereocenters.
Available chemical reference information describes Zastaprazan as a white to off-white solid powder. Its calculated XLogP3-AA value is approximately 4.4, indicating relatively lipophilic characteristics. PubChem reports one hydrogen-bond donor, three hydrogen-bond acceptors and a topological polar surface area of approximately 49.6 Ų.
These physicochemical characteristics are relevant to pharmaceutical formulation and solid-state development.
Zastaprazan's aqueous solubility is dependent on pH, temperature, solid form and experimental conditions. Publicly accessible authoritative sources reviewed for this page do not establish a sufficiently reliable universal numerical water-solubility value suitable for use as a general API specification.
For this reason, a fabricated numerical solubility value should not be included in a commercial CMS specification. Solubility should instead be described using the validated analytical method and the applicable API specification.
Zastaprazan may also exist in different solid forms or salt forms. A zastaprazan citrate form has been reported separately, with CAS 2936619-43-9 and molecular formula C28H34N4O8. Therefore, Zastaprazan free compound and Zastaprazan citrate should not be treated as chemically identical materials.
Quality control of Zastaprazan API can involve orthogonal analytical techniques including HPLC, FTIR, LC-MS and NMR.
HPLC is particularly relevant for quantitative assay and related-substance testing. Identity testing can be supported through chromatographic and spectroscopic methods, while LC-MS can provide molecular confirmation.
Solid-state characterization can also be important for Zastaprazan because polymorphism and other solid-form characteristics may influence pharmaceutical performance. Patent literature relating to Zastaprazan compounds describes analytical techniques including XRPD, DSC, TGA, DVS and NMR for characterization of solid forms.
For pharmaceutical-grade Zastaprazan, quality control should address identity, assay, related substances, residual solvents, water content and elemental impurities according to the applicable specification.
Because Zastaprazan is a relatively new pharmaceutical active ingredient and does not have a broadly established public pharmacopoeial monograph comparable with older APIs, universal numerical limits should not be invented for individual impurities, total impurities, loss on drying or residue on ignition.
A commercial API specification should instead be based on the manufacturer's validated analytical methods, regulatory requirements, customer specification and applicable quality agreement.
Zastaprazan API is relevant to pharmaceutical companies involved in gastrointestinal drug development, P-CAB formulations and acid-suppression therapies.
A suitable API manufacturing and supply program should provide appropriate analytical characterization and batch-specific quality documentation. Important quality attributes include chemical identity, assay, related substances, residual solvents, water content, elemental impurities and solid-state characteristics.
Zastaprazan should be clearly identified by its CAS number 2133852-18-1, molecular formula C22H26N4O, and molecular weight approximately 362.47 g/mol to distinguish it from its citrate salt and other related forms.
Zastaprazan should be stored in appropriate pharmaceutical packaging under controlled environmental conditions established through stability studies. Protection from excessive heat, moisture and unsuitable environmental exposure is recommended.
The specific storage conditions should be based on validated stability data for the API form, packaging configuration and intended shelf life.
| Parameter | Specification |
|---|---|
| Appearance | white to off-white crystalline powder |
| Identification | IR & HPLC compliant |
| Assay (HPLC) | NLT 98.0% |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 20 ppm |
| Individual Impurity | NMT 0.5% |
| Total Impurities | NMT 2.0% |
| Water Content | NMT 1.0% |