Download full text in PDF Opens in a new window. Article suggestions will be shown in a dialog on return to ScienceDirect. ... Please enable JavaScript to use all the features on this page. ... A novel method derived from Kaden's modification 1 of the Richman and Atkins's cyclization 2 using tosylated synthons allows the unequivocal synthesis of 1 and 8-monofunctionalized 1,4,8,12-tetraazacyclo-pentadecane. Both syntheses are described.