5-Amino-1MQ is a small-molecule inhibitor of nicotinamide N-methyltransferase (NNMT), structurally distinct from peptide research compounds — it’s an isoquinoline derivative with a molecular weight of 174.2 Da. This different chemistry class means different QC requirements than peptide products.
🧪 5-Amino-1MQ Key Properties
| Property | Value |
|---|---|
| Chemical Name | 5-Amino-1-methylisoquinolinium |
| Molecular Formula | C10H11N2+ |
| Molecular Weight | 174.2 Da |
| Target | NNMT (Nicotinamide N-Methyltransferase) |
| Class | Small molecule inhibitor |
| Solubility | Water, DMSO |
🔬 NNMT Inhibition and Research Relevance
NNMT methylates nicotinamide using S-adenosylmethionine (SAM) as the methyl donor — this reaction consumes methyl groups that would otherwise be available for DNA and histone methylation, linking NNMT activity to epigenetic regulation. 5-Amino-1MQ inhibits NNMT with reported IC50 values in the low micromolar range, making it a useful tool compound for studying the metabolic-epigenetic interface.
🧫 Quality Verification for Small Molecules vs Peptides
Small molecule QC is fundamentally different from peptide QC — NMR spectroscopy is the primary identity confirmation method, not mass spectrometry.
- NMR: 1H NMR and 13C NMR should match reference spectra for 5-Amino-1MQ. This is the gold standard for small molecule identity
- HPLC: ≥98% purity at 254 nm detection wavelength
- Mass Spec: Confirms molecular ion at m/z 174.2 (ESI+)
- Elemental analysis: Optional but recommended for publication-quality work
- Counter-ion: 5-Amino-1MQ is commonly supplied as the iodide salt. Confirm counter-ion if your experiment is ion-sensitive
⚠️ Small Molecule-Specific Handling
- Weighing: Use an analytical balance — small molecules are dosed by mass, not by “vial content”
- Solubility: DMSO stock solutions at 10-50 mM are standard. Confirm solubility in your specific assay buffer
- DMSO concentration: Keep final DMSO <0.1% in cell-based assays to avoid solvent toxicity
- Light sensitivity: Protect from light — isoquinolinium compounds can photodegrade
- Storage: Desiccated at -20°C for long-term. Room temperature for short-term (<1 month)
❓ FAQ
Q: Why does 5-Amino-1MQ need NMR instead of just HPLC/MS?
A: Small molecules can have identical masses but different structures (isomers). NMR provides structural confirmation that mass alone cannot. A compound with the correct mass but wrong structure will produce irrelevant experimental results — NMR is the only technique that catches this.
Q: What purity is acceptable for 5-Amino-1MQ in enzyme inhibition assays?
A: ≥98% by HPLC. Enzyme assays are sensitive to trace inhibitors — a 2% impurity that also inhibits NNMT will confound your IC50 calculations. For quantitative pharmacology, ≥99% with NMR confirmation is the recommended standard.
Q: Is 5-Amino-1MQ stable in solution?
A: DMSO stock solutions at -20°C are stable for 3-6 months. Aqueous solutions should be prepared fresh for each experiment. Avoid freeze-thaw cycles of DMSO stocks — aliquot on day one.