Synthesis, characterization, and structure of a new N-nitrosamine of cyclam (1,4,8,11-tetraazacyclotetradecane) - Sousa, Alda Karine M. H.; Sousa, Jackson Rodrigues de; Santiago, Marcelo O.; Longhinotti, Elisane; Batista, Alzir A.; Ellena, Javier; Castellano, Eduardo Ernesto; Lopes, Luiz Gonzaga de França; Moreira, Ícaro S. (Tetrahedron Letters, 2005)