Radiolabeling, synthesis and biological evaluation of enantiomerically enriched 1-methylpropyl 2-imidazolyl disulfide

Synthetic methods were developed to produce chiral thioredoxin (Trx) inhibitor, 1-methylpropyl 2-imidazolyl disulfide (IV-2), in either enantiomerically enriched or radiolabeled forms. The enantiomerically enriched products underwent further biological evaluation in EMT6 cells in vitro to test cytotoxicity, as well as being subjected to reaction kinetics experiments with the protein, Trx.; The synthesis of radiolabeled IV-2 was carried out from basic building blocks to facilitate the incorporation of a 14C-label in the alkyl portion of the molecule. Utilizing a Grignard reaction, 2-butanol was initially produced from iodomethane and propanaldehyde, both commercially available entities. Further reaction of this alcohol with p-toluenesulfonyl chloride and thiourea provided 2-butanethiol in a yield of ∼57%. This thiol was used as a starting material in the synthesis of IV-2, with a final overall yield of 13%.; The biological activity, to determine the contribution of each enantiomeric form of IV-2, was assessed with two different assays that measure the cytotoxic potential of the IV-2 enantiomers.; Enzyme kinetic assays were used to determine whether there was any reactivity differences of the pure enantiomers of IV-2 with thioredoxin within a short time frame. (Abstract shortened by UMI.)...