Dota → 1,4,7,10-Tetraazacyclododecane
Reaction equation
[CH2:1]1[N:12](CC(O)=O)[CH2:11][CH2:10][N:9](CC(O)=O)[CH2:8][CH2:7][N:6](CC(O)=O)[CH2:5][CH2:4][N:3](CC(O)=O)[CH2:2]1.[CH2:29]1[CH2:42][N:41](CC(O)=O)[CH2:40][CH2:39][N:38](CC(O)=O)[CH2:37][CH2:36][CH2:35][N:34](CC(O)=O)[CH2:33][CH2:32][N:31](CC(O)=O)[CH2:30]1>>[NH:3]1[CH2:4][CH2:5][NH:6][CH2:7][CH2:8][NH:9][CH2:10][CH2:11][NH:12][CH2:1][CH2:2]1.[NH:31]1[CH2:30][CH2:29][CH2:42][NH:41][CH2:40][CH2:39][NH:38][CH2:37][CH2:36][CH2:35][NH:34][CH2:33][CH2:32]1Participants
4
Procedure
Accordingly, the invention provides a method for the synthesis of 1,4,7,10-tetraazacyclododecane N,N',N",N'"-tetraacetic acid (DOTA) and 1,4,8,11-tetraazacyclotetradecane N,N',N",N'"-tetraacetic acid (TETA) (Formula I). For this purpose 1,4,7,10-tetraazacyclododecane and 1,4,8,11-tetraazacyclotetradecane (Formula II) are provided and cyanomethylated using acid, formaldehyde, and cyanide compound yielding a tetranitrile (Formula III) which precipitates upon the addition of base.. The tetranitrile (Formula III) is hydrolyzed followed by acidification, evaporation to dryness, reconstitution and precipitation to give DOTA or TETA. ##STR5##