Cyclen
[CAS# 294-90-6]

Identification

• Classification: Organic raw materials >> Amino compound >> Sulfonic acid amino compound
• Name: Cyclen
• Synonyms: 1,4,7,10-Tetraazacyclododecane
• Molecular Formula: C₈H₂₀N₄
• Molecular Weight: 172.27
• CAS Registry Number: 294-90-6
• EC Number: 425-450-9
• SMILES: C1CNCCNCCNCCN1

Properties

• Solubility: 1e+006 mg/L (25 °C water)
• Density: 0.9±0.1 g/cm³, Calc.^*
• Index of Refraction: 1.424, Calc.^*
• Melting point: 127.01 °C
• Boiling Point: 283.8±8.0 °C (760 mmHg), Calc.^*, 330.67 °C
• Flash Point: 129.5±13.5 °C, Calc.^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS09 Danger
• Risk Statements: H302-H312-H314-H400-H410
• Safety Statements: P260-P264-P270-P273-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P362+P364-P363-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Serious eye damage	Eye Dam.	1	H318
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Acute toxicity	Acute Tox.	3	H311
Skin corrosion	Skin Corr.	1B	H314
Skin corrosion	Skin Corr.	1	H314
Acute toxicity	Acute Tox.	4	H312

Discovery and Applications

Cyclen, short for 1,4,7,10-tetraazacyclododecane, stands as a remarkable discovery in the realm of coordination chemistry. It was first synthesized in the mid-20th century through systematic chemical modifications aimed at creating macrocyclic compounds with unique properties. Cyclen's discovery marked a significant advancement in the field of metal coordination chemistry, as its structure allows for the formation of stable complexes with metal ions.

Cyclen and its derivatives are widely utilized in metal chelation therapy for the treatment of heavy metal poisoning and metal ion imbalances. Their ability to selectively bind to metal ions such as copper, zinc, and iron helps remove excess metals from the body, preventing their toxic effects and restoring physiological metal homeostasis. Cyclen derivatives, known as macrocyclic chelators, are employed as contrast agents in magnetic resonance imaging (MRI). By chelating paramagnetic metal ions such as gadolinium, Cyclen enhances the contrast between different tissues and organs, improving the visualization of anatomical structures and pathological changes in diagnostic imaging. Cyclen-based ligands serve as catalysts in various chemical reactions, including asymmetric synthesis, organic transformations, and polymerization processes. Their coordination properties and structural rigidity enable efficient catalytic activation of substrates, facilitating the synthesis of complex molecules with high yields and selectivity. Cyclen and its derivatives play a pivotal role in supramolecular chemistry, where they serve as building blocks for the construction of molecular cages, hosts, and receptors. Their ability to form stable complexes with guest molecules enables the design of functional materials with tailored properties for applications in drug delivery, sensing, and molecular recognition. Cyclen-based compounds are valuable tools in biomedical research for studying metal ion metabolism, protein structure, and enzyme function. They are utilized as probes and modulators of metal-dependent biological processes. Cyclen scaffolds are integrated into the design of pharmaceutical agents for enhancing drug stability, solubility, and targeting. Cyclen-based drugs exhibit improved pharmacokinetic properties and reduced off-target effects, making them attractive candidates for the development of novel therapeutic agents for cancer, infectious diseases, and neurological disorders.

References

2023. Synthesis of tris- and pentakis(tetra-armed cyclen) and their complexing properties towards silver(I) ions, _Journal of Inclusion Phenomena and Macrocyclic Chemistry_, 103(5-6)
DOI: https://doi.org/10.1007/s10847-023-01189-y

2021, Synthesis of DOTA-pyridine chelates for 64Cu coordination and radiolabeling of αMSH peptide, _EJNMMI Radiopharmacy and Chemistry_, 6(1)
DOI: https://doi.org/10.1186/s41181-020-00119-4

2012, Biodegradable cyclen-based linear and cross-linked polymers as non-viral gene vectors, _Bioorganic & Medicinal Chemistry_, 20(4)
DOI: https://doi.org/10.1016/j.bmc.2012.01.016