Synthesis and Characterization of Thiol Containing Furoxan Derivatives as Coligands for the Preparation of Potential Bioreductive Radiopharmaceuticals

Synthetic chalcones, flavanones, and flavones as antitumoral agents: biological evaluation and structure-activity relationships

A series of synthetic chalcones, flavanones, and flavones has been synthesized and evaluated for antitumor activity against the human kidney carcinoma cells TK-10, human mammary adenocarcinoma cells MCF-7 (estrogen receptor-positive), and human colon adenocarcinoma cells HT-29. The most active series is the chalcone ones with the best results against TK-10 and HT-29 cells. Fourteen out of 53 analyzed compounds resulted very active against at least two of the studied tumoral cells. Alkaline single cell gel electrophoresis, comet assay, was performed as a study of the chromosomal aberrations promoted by the compounds on normal cells. Four active and two inactive chalcones were studied in the comet assay against normal human kidney cells (HK-2). A structure-activity relationship analysis of these compounds was performed and for 4- and 3,4-disubstituted derivatives a quantitative correlation was obtained in the case of anti-HT-29 activity.

Design and evaluation of “3 + 1” mixed ligand oxorhenium and oxotechnetium complexes bearing a nitroaromatic group with potential application in nuclear medicine oncology

The synthesis and evaluation of a series of oxotechnetium and oxorhenium complexes containing a nitroaromatic moiety as potential radiopharmaceuticals for targeting tumour hypoxia is presented. 99mTc labelling was performed in high yield (>85%) and radiochemical purity (>90%). Their structure was corroborated by means of the rhenium complexes. Reduction potentials were in the range for bioreducible compounds. 99mTc complexes III-VI were selected for "in vivo" experiments in view of the results of cytotoxicity studies. Biodistribution in normal animals was characterized by high initial blood, lung and liver uptake, fast blood and soft tissue depuration and preferential excretion via the hepatobiliary system. Initial tumour uptake was moderate but tumour/muscle ratios for complexes III and IV, were favourable at all time points. Although the results are encouraging further development is still necessary in order to achieve higher tumour uptake and lower gastrointestinal activity.