Dopamine D3 receptor antagonists: the quest for a potentially selective PET ligand. Part 3: Radiosynthesis and in vivo studies.

Compound 1 is a potent and selective antagonist of the dopamine D(3) receptor. With the aim of developing a carbon-11 labeled ligand for the dopamine D(3) receptor, 1 was selected as a potential PET probe. [(11)C]1 was obtained by palladium catalyzed cross coupling using [(11)C]cyanide and 4 with a specific activity of 55.

Targeting small-cell lung cancer with novel fluorescent analogs of somatostatin.

Early, accurate detection of small-cell lung cancer (SCLC), before it becomes systemic, is essential for successful treatment. Fluorescence-based imaging provides safe, sensitive detection of malignancies. Targeted delivery of fluorophores increases sensitivity of endoscopic imaging.

Backbone metal-cyclization: a novel approach for simultaneous peptide cyclization and radiolabeling. Application to the combinatorial synthesis of rhenium-cyclic somatostatin analogs.

A novel approach for the combinatorial synthesis of backbone-derived metal-cyclic peptide libraries is presented. In this approach the metalo-cyclic peptides are prepared from their linear precursors through complexation of a metal atom via two hemi-chelating arms located on the peptide backbone. Thus, cyclization and metal labeling of the peptides are achieved simultaneously.

Effects of androgens on aromatase activity and 11C-vorozole binding in granulosa cells in vitro.

Background: Locally produced androgens and estrogens are important in the hormonal regulation of follicular development. The present study aimed to further elucidate the mechanism through which androgens exert their ambivalent effects on aromatization.

Methods: Non-cultured human granulosa-luteal cells (GC) were treated with different concentrations of androstenedione (A4), testosterone (T), 5alpha-androstane-3,17-dione (5alpha-A) and dihydrotestosterone (DHT).