
Cyclen (1,4,7,10-tetraazacyclododecane) is an aza-crown ether with the formula (CH2CH2NH)4. It is a white solid. It forms coordination complexes with metal cations and is used to synthesize the chelating agent DOTA which has several medical applications. Being structurally simple, symmetrical, and polyfunctional, cyclen has been widely investigated.
Cyclen (1,4,7,10-tetraazacyclododecane) is an aza-crown ether with the formula (CH2CH2NH)4. It is a white solid. It forms coordination complexes with metal cations and is used to synthesize the chelating agent DOTA which has several medical applications. Being structurally simple, symmetrical, and polyfunctional, cyclen has been widely investigated.
== Synthesis == Some syntheses exploit the Thorpe-Ingold effect to facilitate ring-formation. Illustrative is the reaction of the deprotonated tosylamides with ditosylates: TsN(CH2CH2NTsNa)2 + TsN(CH2CH2OTs)2 → (TsNCH2CH2)4 The resulting macrocycle can be deprotected with strong acid. Base gives the tetramine.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).