轮环藤宁

I. Basic Information (CAS: 294-90-6)

Chemical Name: Cyclen

Molecular Formula: C₈H₂₀N₄, Molecular Weight: 172.27

Appearance: White/grayish-white crystalline powder

II. Uses and Characteristics

Core Uses

Pharmaceutical Intermediate (Most Core): Key precursor for synthesizing MRI contrast agents (such as gadobenate dimeglumine); used in radiopharmaceuticals, myocardial protection, and stone removal, etc.

Strong coordination ability, forms thermodynamically and kinetically stable metal complexes, reducing the toxicity of free metals

Good water solubility and easy derivatization, suitable for pharmaceutical and functional material development

III. Parameters

Boiling Point: 283.8±8.0 °C (760 mmHg)

Density: ~0.9 g/cm³

pKa: Polyprotonated, pKa₁≈10.7, pKa₂≈9.6, pKa₃≈2.7, pKa₄≈1.8

Storage: 2–8 °C, dry, sealed, protected from light

IV. Quality Standards

Purity: ≥99.0%

Moisture: ≤0.5%

Impurities: None

Heavy Metals (Pb, As, Cd, Hg): ≤10 ppm

Residual Solvents: Complies with ICH Q3C

Microbial Limits: Complies with requirements for pharmaceutical excipients

Appearance: White powder

Melting Point: 110–112 °C

Purity (HPLC): ≥99.0%

Moisture: ≤0.3%

Toluene: ≤890 ppm.