DAU5884

Selective muscarinic M3 receptor antagonist

• DAU 5884 is a synthetic small molecule that acts as an antagonist of the muscarinic acetylcholine receptor subtype M₃ (mAChR M₃).

• Its chemical formula (for the hydrochloride form) is C₁₇H₂₂ClN₃O₃, molecular weight ~ 351.8 Da. 

• It has good purity in commercially sold research reagent form (≥ 98–99%) and is described for research use only. 

Mechanism / Biological Activity

• As an M₃ receptor antagonist, DAU 5884 binds to the M₃ muscarinic receptor and prevents activation by the natural ligand (acetylcholine) or agonists. 

• The M₃ receptor is Gq‑coupled and involved in various functions such as smooth muscle contraction, glandular secretion, and certain CNS functions. 

• In functional assays:

  • It inhibits methacholine‑dependent effects (methacholine is a muscarinic agonist) on contractility and cell proliferation in bovine tracheal smooth muscle.

  • It has been noted to exhibit IC₅₀ values in the range of ~ 8 to ~ 131 nM in competitive binding assays against [^3H]NMS (a muscarinic antagonist radioligand) at M₃ receptors. 

 Use in Research

• Because it is selective for the M₃ subtype, DAU 5884 is used in research to dissect the role of M₃ receptors in physiological and pathophysiological settings (e.g., airway smooth muscle contraction, proliferative responses, cholinergic regulation).

• Example: It has been used to study how M₃ receptor activation contributes to airway smooth muscle growth and contraction in models of respiratory disease. ERS Publications+1

• Another example: It has been used in neuroscience research (e.g., in studies of cholinergic synapse degeneration and cognitive impairment) to understand the influence of muscarinic signalling. 

 Important Considerations

• Despite being labelled as “selective”, binding to other muscarinic subtypes (or off‑target effects) is always a possibility depending on concentration, cell type, species, etc. (One source notes “discriminates between M4 and M2” in another context) 

• As with many pharmacological antagonists: the context of use (in vitro vs in vivo), dosing, receptor expression levels, species differences, and presence of endogenous ligand matter a lot.

• Always ensure you have the Certificate of Analysis (CoA) and check the lot‐specific purity.

• Since it is a research reagent, not approved for clinical or diagnostic use, ensure it is handled according to institutional safety/ethics policies.