Prepn. of L-(selenium-75)-seleno:methionine - by reaction of selenium-75 with methyl:lithium, followed by reaction with L-alpha-amino-gamma bromo:butyric acid

摘要

Prepn. of L-(75Se)-selenomethionine (I) of high specific activity in amts. up to 1 Curie comprises: (a) reaction of 75Se of corresp. activity with an eight-fold molar excess of ethereal OMeli soln. (based on Se) in a remote-controlled apparatus; and (b) reaction of the resultant Me75Seli (II) with an ethanolic soln of two equivs. of L-alpha-amino-gamma-bromo-butyric acid hydrobromide (III) at room temp. in the same appts. Both processes are carried out under Argon. USE/ADVANTAGE - (I) is a useful radiopharmaceutical used for depiction of the pancreas. The process may be carried out in small amts. of liquid and is simpler than prior-art processes as step (b) takes place at room temp. Isolation of (I) is easier than in previous processes