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

Executive Summary: 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (A2845) is a chemically defined, high-purity H+,K+-ATPase inhibitor, achieving an IC50 of 5.8 μM against the enzyme and 0.16 μM for histamine-induced gastric acid secretion (APExBIO product page). The compound’s purity (≥98%) is verified by HPLC and NMR. It is insoluble in water and ethanol but soluble to ≥17.27 mg/mL in DMSO, enabling reliable experimental workflows. A2845 is solely intended for scientific research, with protocols favoring -20°C storage for maximum stability. This article extends mechanistic and workflow insights for antiulcer and gastric acid secretion studies by integrating recent advances and clarifying common pitfalls (Kong et al., 2025).

Biological Rationale

Gastric acid secretion is mediated by the H+,K+-ATPase enzyme, also known as the proton pump, which exchanges intracellular hydrogen ions for extracellular potassium ions in gastric parietal cells. This enzymatic activity is a central target in the pathophysiology of acid-related disorders, including peptic ulcer disease and gastroesophageal reflux disease (GERD). Inhibitors of H+,K+-ATPase, such as A2845, are essential for modeling acid suppression and antiulcer activity in vitro and in vivo (Revolutionizing Gastric Acid Secretion Research), extending the precision and reproducibility of experimental studies. Unlike conventional agents, A2845 features a trifluoromethoxy substituent and a thiophene-2-carboxamide backbone, conferring high specificity and potency. APExBIO supplies A2845 for exclusive scientific research use, with validated analytical quality and batch reproducibility (product page).

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

A2845 acts as a selective, reversible inhibitor of the H+,K+-ATPase enzyme. It binds to the catalytic α-subunit, blocking ATP hydrolysis and subsequent proton translocation. This inhibition is dose-dependent, with an IC50 of 5.8 μM for the enzyme and 0.16 μM for histamine-induced acid secretion in cellular assays (APExBIO). By preventing proton pump activity, A2845 suppresses gastric acid formation, thereby producing antiulcer effects in relevant models. The compound’s molecular weight is 345.42 Da, with the formula C17H19N3O3S. Structural differences from classic IC omeprazole analogs provide increased solubility in DMSO and improved physicochemical stability (Applied Use Cases), supporting its application in complex in vitro and in vivo workflows.

Evidence & Benchmarks

• Demonstrates potent H+,K+-ATPase inhibition in biochemical assays, with an IC50 of 5.8 μM at 25°C, pH 7.4 (APExBIO, product page).
• Suppresses histamine-induced gastric acid secretion at an IC50 of 0.16 μM in isolated cellular models (APExBIO, product page).
• Purity (≥98%) is validated by HPLC and 1H NMR spectroscopy for each batch (APExBIO, product page).
• Solubility in DMSO is ≥17.27 mg/mL at 20°C; compound is insoluble in water and ethanol (APExBIO, product page).
• Enables reproducible gastric acid secretion and antiulcer activity studies, as demonstrated in comparative protocol reviews (H+,K+-ATPase Inhibitor Workflows).
• Recent studies highlight the role of proton pump inhibitors in gut–brain and gut–liver axis modulation, as shown by neuroinflammation imaging and microbiota research (Kong et al., 2025).

Applications, Limits & Misconceptions

A2845 is suited for cellular and animal studies requiring precise H+,K+-ATPase inhibition. It is used in:

• Gastric acid secretion inhibition assays.
• Peptic ulcer disease model development.
• Mechanistic studies of the proton pump inhibition pathway.
• Pharmacological profiling relative to conventional IC omeprazole analogs (Applied Use Cases).
• Investigations into gut–liver–brain axis interactions, leveraging recent neuroinflammation imaging technologies (Kong et al., 2025).

For a comprehensive mechanistic update, this article clarifies the compound’s utility in advanced models, extending beyond the scope of previous reviews by integrating neuroinflammation findings and troubleshooting insights.

Common Pitfalls or Misconceptions

• Not effective as a therapeutic in humans—A2845 is strictly for research use only; it is not approved for diagnostic or medical applications (APExBIO).
• Compound is not stable in solution for long-term storage; always prepare fresh aliquots and store powder at -20°C.
• Insoluble in water and ethanol—attempting to dissolve in these solvents will result in precipitation and assay failure.
• Not suitable for workflows requiring aqueous delivery without DMSO co-solvent.
• Does not inhibit other ATPases or unrelated gastric enzymes; activity is selective for H+,K+-ATPase.

Workflow Integration & Parameters

Integration of A2845 into gastric acid secretion and antiulcer activity studies requires rigorous protocol adherence:

• Reconstitute in DMSO to a minimum concentration of 17.27 mg/mL; vortex until fully dissolved.
• Aliquot and store at -20°C; avoid freeze-thaw cycles for purity retention.
• Recommended working concentrations range from 0.1–10 μM, depending on cellular model sensitivity and endpoint.
• Combine with validated control inhibitors (e.g., IC omeprazole) for benchmarking (Applied Use Cases).
• Refer to protocol optimization and troubleshooting guides for best practices (H+,K+-ATPase Inhibitor Workflows).
• This article updates and clarifies the practical workflow recommendations of Optimizing Gastric Acid Secretion Research by emphasizing solubility and storage nuances.

Conclusion & Outlook

APExBIO’s 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (A2845) sets a reproducible and validated standard for research on H+,K+-ATPase signaling, antiulcer agents, and gastric acid secretion inhibition. Its robust physicochemical and inhibitory benchmarks support advanced mechanistic and pharmacological investigations. Ongoing research, including neuroinflammation imaging and the gut–liver–brain axis, positions A2845 as a versatile tool for translational acid-related disorder models (Kong et al., 2025). For full protocol details and ordering, refer to the A2845 product page.