The structure of McN-5652.

Abstract The configuration of the diastereoisomers of 6-(4-methylthiophenyl)-1,2,3,5,6,10b-hexahydropyrrolo[2,1- a ]isoquinoline 1 (McN-5652) is determined and unequivocally assigned by NMR spectroscopy (NOE measurements) and an X-ray structural analysis of the trans diastereoisomer. The enantiomers of cis - 1 are separated by preparative HPLC on a chiral phase. One of the enantiomers of cis - 1 represents the precursor for imaging the serotonin 5-HT transporter with positron emission tomography (PET).