<p> The estrogen receptor (ER) plays an integral role in the proliferation of hormone dependent breast cancer. Recently a number of organometallic compounds and closocarboranes, which demonstrate affinity for the estrogen receptor, were prepared as novel types of anti-estrogens. This thesis describes the synthesis and characterization of a new class ofinorganic anti-estrogens derived from Re-metallocarboranes. </p> <p> Chapter 2 describes the first series of targets which include three monoarylated Re-metallocarboranes. Two different synthetic routes were used to complex the [Re(C0)3t core to carborane ligands, one of which involves microwave irradiation of a one pot mixture that produces the desired complexes in almost complete conversion ratios. One compound, 2.10, contains a single phenol substituents, which is predicted to show ER binding affinity based on previous reports ofthe closo-carborane analogue. </p> <p> Chapter 3 describes the synthesis and characterization of diarylated Remetallocarboranes. Two of the compounds, 3.7 and 3.8, are expected to show high binding affinity for the ER because they are inorganic analogues of the well known antiestrogen Tamoxifen. </p> / Thesis / Master of Science (MSc)