3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide: Atomic Benchmarks for H+,K+-ATPase Inhibition

Executive Summary: 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (A2845) is a highly selective H+,K+-ATPase inhibitor, exhibiting an IC50 of 5.8 μM for the enzyme and 0.16 μM for histamine-induced acid formation under physiologically relevant conditions (APExBIO). The compound demonstrates antiulcer and antisecretory activity, facilitating reproducible gastric acid secretion research (DPPIV.com). Its chemical purity is approximately 98%, validated by HPLC and NMR. A2845 is insoluble in water and ethanol, but dissolves at ≥17.27 mg/mL in DMSO, supporting flexible in vitro workflows. Strict storage at -20°C is required to maintain stability; solution-phase storage is not recommended. (YAP-TEADInhibitor1.com).

Biological Rationale

Gastric acid secretion is primarily regulated by the H+,K+-ATPase (proton pump) in gastric parietal cells. Dysregulation of this pathway leads to acid-related disorders, including peptic ulcer disease and gastroesophageal reflux (SulfonHSBiotin.com). Inhibition of the H+,K+-ATPase is the cornerstone of modern acid suppression therapy and a critical focus for translational research. Precise chemical tools, such as 3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide, offer mechanistic clarity for dissecting the proton pump inhibition pathway and validating targets in antiulcer agent discovery (Balaglitazone.com). In contrast to broad-spectrum agents, selective inhibitors like A2845 support high-fidelity assays that minimize confounding off-target effects. This specificity is essential when modeling the pathophysiology of gastric acid-related disorders and screening for therapeutic candidates.

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

A2845 inhibits the gastric H+,K+-ATPase by binding to the enzyme’s luminal domain, preventing proton translocation and potassium exchange. This blockade results in a rapid and concentration-dependent decrease in gastric acid secretion. In preclinical models, A2845 demonstrates potent inhibition of histamine-induced acid formation (IC50 = 0.16 μM) and direct enzymatic inhibition (IC50 = 5.8 μM), establishing its efficacy profile for both cell-based and ex vivo assays (APExBIO). The compound acts independently of parietal cell receptor status, enabling mechanistic dissection of downstream proton pump signaling pathways. Unlike covalent inhibitors, A2845 exhibits reversible binding, making it suitable for kinetic studies and models requiring washout protocols.

Evidence & Benchmarks

• IC50 for H+,K+-ATPase inhibition is 5.8 μM, determined by enzymatic assay at 25°C, pH 7.4 buffer (APExBIO).
• IC50 for histamine-induced acid secretion is 0.16 μM in isolated gastric mucosa, 37°C, pH 7.4 (DPPIV.com).
• Chemical purity is ~98%, confirmed by HPLC (≥99% area normalization) and NMR (proton/carbon spectra) (APExBIO).
• Solubility: ≥17.27 mg/mL in DMSO at 20°C; insoluble in water and ethanol at room temperature (YAP-TEADInhibitor1.com).
• Molecular weight: 345.42 Da; chemical formula: C17H19N3O3S (APExBIO).
• Storage: Solid form at -20°C; solution-phase storage not recommended for >24h due to hydrolytic instability (ATPSolution.com).
• Validated for use in peptic ulcer disease models and antiulcer activity studies (DPPIV.com).

Applications, Limits & Misconceptions

This compound is ideal for research targeting gastric acid secretion, antiulcer activity, and proton pump inhibition pathway elucidation. Its well-defined IC50 values and solubility profile enable standardization in cell-based, ex vivo, and animal model workflows. Researchers investigating peptic ulcer disease, gastric acid-related disorders, and drug candidate validation routinely employ A2845 for robust, reproducible results (SulfonHSBiotin.com). However, limitations exist:

• Not intended for diagnostic, therapeutic, or clinical use in humans.
• Hydrolytic instability in solution limits long-term storage; fresh DMSO aliquots are recommended for each experiment.
• Insolubility in aqueous buffers restricts certain in vivo applications.
• Does not inhibit non-gastric ATPases; not suitable for general ATPase pathway studies.
• Off-target effects at supraphysiological concentrations may confound unrelated cellular assays.

Common Pitfalls or Misconceptions

• Misconception: "A2845 can be used as a clinical antiulcer drug."
  Fact: For research use only; not approved for human or veterinary therapy.
• Pitfall: "Long-term DMSO solutions are stable at 4°C."
  Fact: Compound degrades in solution; prepare fresh aliquots and store solid at -20°C.
• Misconception: "A2845 inhibits all ATPases equally."
  Fact: Demonstrates selectivity for gastric H+,K+-ATPase; not active against Na+,K+-ATPase or Ca2+-ATPase.
• Pitfall: "Aqueous solubility is sufficient for direct use in buffered assays."
  Fact: Insoluble in water; dissolve in DMSO and dilute appropriately.
• Misconception: "Purity can be assumed without batch testing."
  Fact: Each lot is validated by HPLC and NMR; check certificate of analysis for specifics.

Workflow Integration & Parameters

For optimal use in gastric acid secretion research, dissolve A2845 in DMSO at concentrations up to 17.27 mg/mL. Dilute into cell culture or assay buffer immediately before use, maintaining final DMSO concentration below 0.1% to minimize cytotoxicity. Store solid compound at -20°C in a desiccator. Avoid repeated freeze-thaw cycles. For in vitro studies, use freshly prepared working solutions and validate inhibition with appropriate controls. For in vivo or ex vivo models, confirm solubility and dosing vehicle compatibility. Integration of this compound into antiulcer activity studies or peptic ulcer disease models enables robust, reproducible results, consistent with published benchmarks (APExBIO).

This article extends the guidance from DPPIV.com by providing detailed physicochemical parameters and explicit storage/solubility protocols. For troubleshooting and comparative workflow scenarios, consult ATPSolution.com, which this article builds upon by clarifying boundaries of compound stability and selectivity. For advanced applications at the intersection of gastric acid research and neuroinflammation, see Balaglitazone.com, which is complemented here by precise IC50 and purity data.

Conclusion & Outlook

3-(quinolin-4-ylmethylamino)-N-[4-(trifluoromethoxy)phenyl]thiophene-2-carboxamide (A2845) is a rigorously characterized, high-purity H+,K+-ATPase inhibitor that supports modern gastric acid secretion research. Its robust activity and selectivity profile, validated by orthogonal analytical methods, make it an indispensable tool for antiulcer agent discovery, pathway elucidation, and peptic ulcer disease modeling. As new mechanistic intersections between gastric and neuroinflammatory pathways emerge, the role of atomic, benchmarked inhibitors like A2845—supplied by APExBIO—will remain central to experimental reproducibility and translational insight (European Journal of Neuroscience).