{{chembox | Watchedfields = changed | verifiedrevid = 470614378 | ImageFile = N1,N1'-(ethane-1,2-diyl)bis(ethane-1,2-diamine) 200.svg | ImageFile_Ref = | ImageSize = 220 | ImageName = Skeletal formula of triethylenetetramine | ImageFile1 = Triethylenetetramine-3D-balls.png | ImageFile1_Ref = | ImageSize1 = 220 | ImageName1 = Ball and stick model of triethylenetetramine | ImageFile2 = Triethylenetetramine-3D-spacefill.png | ImageFile2_Ref = | ImageSize2 = 220 | ImageName2 = Spacefill model of triethylenetetramine | PIN = N1,N1′-(Ethane-1,2-diyl)di(ethane-1,2-diamine) | OtherNames = {{Unbulleted list| N,N-Bis(2-aminoethyl)ethane-1,2-diamine | TETA | trien | trientine (INN) | trientine dihydrochloride | MK-0681 }} |Section1= |Section2= |Section3= |Section5= |Section9= }}Triethylenetetramine (TETA and trien), also known as trientine''' (INN) when used medically, is an organic compound with the formula [CH2NHCH2CH2NH2]2. The pure freebase is a colorless oily liquid, but, like many amines, older samples assume a yellowish color due to impurities resulting from air-oxidation. It is soluble in polar solvents. The branched isomer tris(2-aminoethyl)amine and piperazine derivatives may also be present in commercial samples of TETA. The hydrochloride salts are used medically as a treatment for copper toxicity. Uses Epoxy uses The reactivity and uses of TETA are similar to those for the related polyamines ethylenediamine and diethylenetriamine. It is primarily used as a crosslinker ("hardener") in epoxy curing. TETA, like other aliphatic amines, react quicker and at lower temperatures than aromatic amines due to less negative steric effects since the linear nature of the molecule provides it the ability to rotate and twist. Medical uses The hydrochloride salt of TETA, referred to as trientine hydrochloride, is a chelating agent that is used to bind and remove copper in the body to treat Wilson's disease, particularly in those who are intolerant to penicillamine. Some recommend trientine as first-line treatment, but experience with penicillamine is more extensive. Trientine hydrochloride (brand name Syprine) was approved for medical use in the United States in November 1985. Trientine tetrahydrochloride (brand name Cuprior) was approved for medical use in the European Union in September 2017. It is indicated for the treatment of Wilson's disease in adults, adolescents and children five years of age or older who are intolerant to D-penicillamine therapy. Trientine dihydrochloride (brand name Cufence) was approved for medical use in the European Union in July 2019. It is indicated for the treatment of Wilson's disease in adults, adolescents and children five years of age or older who are intolerant to D-penicillamine therapy. The most common side effects include nausea,