Techniques for the identification of the protein target(s) of small molecules are proving very important following an increase in the use of phenotype-based screening in chemical biology and drug discovery. One approach, known as the yeast-3-hybrid approach, has shown considerable potential. A key factor in the success of this approach is the preparation of a complex molecule referred to as a chemical inducer of dimerisation (CID). The synthesis of two CIDs based on a bioactive tetrahydro-beta-carboline core structure is reported and evidence presented that shows the CIDs are of utility in this approach. A series of chemo- and bioinformatic studies coupled with SAR development inspired the choice of CIDs.