Synthesis of carbon-11 labeled biaryl 1,2,3,4-tetrahydroisoquinoline derivatives and conformationally flexible analogues as new potential PET glioma tumor imaging agents.

Carbon-11 labeled biaryl 1,2,3,4-tetrahydroisoquinoline derivatives and conformationally flexible analogues, 2-(2-(biphenyl-4-yl)ethyl)-6-[(11)C]methoxy-7-methoxy-1,2,3,4-tetrahydroisoquinoline ([(11)C]3); 1-(biphenyl-4-yl)methyl-6,7-dimethoxy-2-[(11)C]methyl-1,2,3,4-tetrahydroisoquinoline (N-[(11)C]7) and 1-(biphenyl-4-yl)methyl-6-[(11)C]methoxy-7-methoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline (O-[(11)C]7); and 2-(biphenyl-4-yl)-N-(3,4-dimethoxy-phenethyl)-N-[(11)C]methyl-ethanamine (N-[(11)C]10) and 2-(biphenyl-4-yl)-N-(3-methoxy-4-[(11)C]methoxy-phenethyl)-N-methyl-ethanamine (O-[(11)C]10), have been synthesized as new potential positron emission tomography (PET) glioma tumor imaging agents, either by O-[(11)C]methylation or by N-[(11)C]methylation of the appropriate precursors using [(11)C]CH(3)OTf and isolated either by a simplified solid-phase extraction (SPE) purification procedure or by HPLC method in 30-55% radiochemical yields decay corrected to EOB, 15-25 min overall synthesis time, and 4.0-6.0 Ci/mumol specific activity at EOB.