Cyclopentamine

Cyclopentamine
Systematic (IUPAC) name
(RS)-1-cyclopentyl-N-methyl-propan-2-amine
Clinical data
Pregnancy cat.  ?
Legal status Uncontrolled
Routes Inhalation
Identifiers
CAS number 102-45-4
ATC code R01AA02
PubChem CID 7608
ChemSpider 7326 Y
UNII WB9Q6M8O60 Y
KEGG D07370 Y
ChEMBL CHEMBL329203 Y
Synonyms N,α-dimethyl-cyclopenaneethylamine
Chemical data
Formula C9H19N 
Mol. mass 141.254
SMILES eMolecules & PubChem
Physical data
Boiling point 171 °C (340 °F)
 Y(what is this?)  (verify)

Cyclopentamine (Clopane, Cyclonarol, Cyclosal, Cyklosan, Nazett, Sinos) is a sympathomimetic alkylamine, classified as a vasoconstrictor. Cyclopentamine was indicated in the past as an over-the-counter (OTC) medication for use as a nasal decongestant, notably in Europe and Australia, but has now been largely discontinued possibly due to the availability, effectiveness, and safety of a structurally similar drug, propylhexedrine.

Contents

Chemistry

Cyclopentamine is the cyclopentane homologue of propylhexedrine, differing only in terms of the contracted ring size of a cyclopentane, containing one -CH2- unit less than the cyclohexyl group.

In terms of the acyclic part of the molecule, both cyclopentamine and propylhexedrine are directly synonymous with methamphetamine, all three molecules containing the 2-methylaminopropyl side-chain. The obvious difference between them is that whereas methamphetamine is an aromatic molecule containing a phenyl group, cyclopentamine and propylhexedrine are entirely aliphatic and contain no delocalized electrons at all. The effect that this has on potency is that the reduced alicyclic-alkylamines are weaker than unsaturated (meth)amphetamine.

Synthesis

Cyclopentamine can be synthesised starting from cyclopentanone and cyanoacetic acid.[1][2]

Condensation of cyclopentanone with cyanoacetic acid in a modified Knoevenagel condensation followed by decarboxylation affords the unsatured nitrile. Reduction of the double bond and subsequent reaction of the product with methylmagnesium halide leads to the methyl ketone. This affords the desired product on reductive amination with methylamine.[3]

Pharmacology

Cyclopentamine acts as a releasing agent of the catecholamine neurotransmitters norepinephrine (noradrenaline), epinephrine (adrenaline), and dopamine.[4] Its effects on norepinephrine and epinephrine mediate its decongestant effects, while its effects on all three neurotransmitters are responsible for its stimulant properties. When ingested orally in sufficient quantities, cyclopentamine produces similar effects to amphetamine, methamphetamine, and propylhexedrine.[5][6]

See also

References

  1. ^ here
  2. ^ here
  3. ^ E. Rohrman, U.S. Patent 2,520,015 (1950)
  4. ^ Schmidt JL, Fleming WW (July 1964). "A Nonsympathomimetic Effect of Cyclopentamine and Beta-Mercaptoethylamine in the Rabbit Ileum.". The Journal of Pharmacology and Experimental Therapeutics 145: 83–6. PMID 14209515. http://www.drugs-forum.com/forum/local_links.php?action=jump&catid=70&id=4116. 
  5. ^ Ghouri MS, Haley TJ (July 1969). "In vitro evaluation of a series of sympathomimetic amines and the beta-adrenergic blocking properties of cyclopentamine.". Journal of Pharmaceutical Sciences 58 (7): 882–4. doi:10.1002/jps.2600580722. PMID 4390216. 
  6. ^ Marley E, Stephenson JD (August 1971). "Actions of dexamphetamine and amphetamine-like amines in chickens with brain transections.". British Journal of Pharmacology 42 (4): 522–42. PMC 1665761. PMID 5116035. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1665761.