3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide: A Benchmark H+,K+-ATPase Inhibitor for Gastric Acid Secretion Research

Executive Summary: 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (SKU: A2845, supplied by APExBIO) is a potent H+,K+-ATPase inhibitor with an IC₅₀ of 5.8 μM for the enzyme and 0.16 μM for histamine-induced acid formation, validated by HPLC and NMR to a purity of ~98% (APExBIO). The compound is insoluble in water/ethanol but dissolves to ≥17.27 mg/mL in DMSO, supporting diverse in vitro workflows (APExBIO). It exhibits robust antisecretory and antiulcer activities, facilitating high-fidelity gastric acid secretion research (acridine-orange.com). Recent literature emphasizes the importance of precise H+,K+-ATPase pathway modulation in disease modeling and antiulcer compound benchmarking (atpsolution.com). The compound is for research use only and is not suitable for diagnostic or therapeutic applications (APExBIO).

Biological Rationale

Gastric acid secretion is regulated by the gastric H+,K+-ATPase, a membrane-bound proton pump in parietal cells. Overactivity of this enzyme is implicated in peptic ulcer disease, gastroesophageal reflux, and other acid-related disorders (Kong et al., 2025). Inhibitors of H+,K+-ATPase, such as 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide, are fundamental to both mechanistic and translational research in gastric acid secretion and antiulcer therapies (cgs21680.com). Precise control of gastric acid output is also relevant for studying the gut-liver-brain axis, as acid-base disturbances can influence gastrointestinal and systemic inflammation pathways (Kong et al., 2025).

Mechanism of Action of 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide

This compound acts as a selective inhibitor of H+,K+-ATPase by binding to the enzyme and preventing the exchange of intracellular H⁺ for extracellular K⁺, thereby blocking gastric acid secretion at the parietal cell membrane. The measured IC₅₀ for H+,K+-ATPase inhibition is 5.8 μM, and for histamine-induced acid formation the IC₅₀ is 0.16 μM (APExBIO, product page). The compound's structure confers selectivity and potency, making it suitable for dissecting the proton pump inhibition pathway in research settings (dmg-peg2000-mal.com). Unlike classical omeprazole analogs, the unique quinolinyl and trifluoromethoxy substituents provide enhanced activity and experimental versatility (balaglitazone.com).

Evidence & Benchmarks

• Demonstrates an IC₅₀ of 5.8 μM for H+,K+-ATPase inhibition under in vitro conditions (pH 7.4, 37°C, 30 min incubation) (APExBIO).
• Inhibits histamine-induced gastric acid formation with an IC₅₀ of 0.16 μM in preclinical models (APExBIO).
• Validated purity of ~98% by HPLC and NMR, ensuring consistent experimental results (APExBIO).
• Outperforms conventional IC omeprazole analogs in precision and solubility for gastric acid secretion research (balaglitazone.com).
• Supports high-fidelity modeling of gastric acid-related disorders, enabling translational research on peptic ulcer disease and proton pump inhibition pathways (atpsolution.com).
• Connects mechanistically to broader research on inflammation and gut-brain-liver axis modulation (Kong et al., 2025).

Applications, Limits & Misconceptions

3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide is appropriate for:

• Preclinical modeling of gastric acid-related disorders (e.g., peptic ulcer, GERD).
• Quantitative analysis of H+,K+-ATPase inhibition kinetics.
• Comparative antiulcer activity studies versus omeprazole analogs.
• Elucidation of the proton pump inhibition and H+,K+-ATPase signaling pathways.

This article extends the discussion in acridine-orange.com by detailing validated evidence for purity and solubility, whereas the previous piece focused on mechanistic boundaries. Compared to atpsolution.com, this review benchmarks quantitative performance metrics and addresses workflow integration, clarifying applications for advanced modeling.

Common Pitfalls or Misconceptions

• Not suitable for diagnostic or therapeutic use: This compound is for research use only and is not approved for clinical applications (APExBIO).
• Insolubility in water and ethanol: Direct dissolution in aqueous or alcoholic buffers is ineffective; DMSO is required for stock solution preparation (APExBIO).
• Degradation in solution: Long-term storage in solution is not recommended; compounds should be stored as solid at -20°C (APExBIO).
• Specificity for proton pump: The inhibitor is selective for H+,K+-ATPase and should not be assumed to affect other ATPases without supporting data (acridine-orange.com).
• Experimental controls: Lack of appropriate vehicle and pathway controls may confound antiulcer activity results (APExBIO).

Workflow Integration & Parameters

For optimal results, the solid compound should be dissolved in DMSO at concentrations up to ≥17.27 mg/mL. Aliquots should be stored at -20°C and thawed immediately before use. For in vitro enzyme assays, a working range of 0.1–10 μM is typical. Preclinical gastric acid secretion models benefit from titrated exposure, with endpoint measurement after 30–60 min incubation at physiological temperature and pH. Purity is validated via HPLC and NMR, supporting reproducibility across experimental replicates (APExBIO). Researchers are encouraged to consult the A2845 kit documentation for detailed parameters. Advanced workflow guidance and troubleshooting can be found in this use-case review, which this article updates with new benchmarks and evidence for antiulcer modeling.

Conclusion & Outlook

3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (APExBIO, SKU: A2845) is a validated, high-purity H+,K+-ATPase inhibitor enabling precise and reproducible research in gastric acid secretion and antiulcer activity. Its robust inhibition profile, superior solubility in DMSO, and documented performance metrics set a benchmark for IC omeprazole analog research. Ongoing studies are expanding its role in disease modeling and mechanistic pathway analysis, supporting the evolution of preclinical antiulcer agent development.