Polyamines are organic compounds having at least two amino groups as part of an otherwise aliphatic chain. The amino groups are usually separated by three or four methylene units, such as putrescine and spermine. Cyclen is the typical example of a class of cyclic polyamines. The polyamines are essential molecules in both eukaryotic and prokaryotic cells, and, therefore, have been isolated from all kinds of living organisms, including humans.1) Especially, the requirement for and the metabolism of polyamines are frequently dysregulated in cancer, and some polyamines can induce diseases caused by neurotoxins.2) Thus, the polyamines, which are available by chemical synthesis, have been attractive for continuing with the study of diseases.3) 
This section shows the typical polyamines and the reagents used for the polyamine chemical synthesis.