Structure-Activity Relationship of New Growth Inhibitors of Trypanosoma cruzi

CINQUE, GÜENDALINA; SZAJNMAN, SERGIO HERNÁN; ZHONG, LI; DOCAMPO, ROBERTO; SCHVARTZAPEL, ANDREA JUDITH; RODRIGUEZ, JUAN BAUTISTA; GROS, EDUARDO GERVASIO

JOURNAL OF MEDICINAL CHEMISTRY

AMER CHEMICAL SOC

Lugar: Columbus; Año: 1998 vol. 41 p. 1540 - 1554

0022-2623

Several drugs bearing the 4-phenoxyphenoxy skeleton, and other closely related structures were designed, synthesized and evaluated as antiproliferative agents against Trypanosoma cruzi, the etiologic agent of Chagas' disease. The new class of drugs was envisioned by modifying the non polar 4-phenoxyphenoxy moiety replacing selected aromatic protons by different groups via electrophilic aromatic substitution reactions as well as introducing a sulfur atom at the polar extreme. Of the designed compounds, sulfur-containing derivatives were shown to be potent antireplicative agents against T. cruzi. Among these drugs, 4-phenoxyphenoxyethyl thiocyanate (compound 56) proved to be an extremely active growth inhibitor of the epimastigote forms of T. cruzi which displayed an IC50 of 2.2 M. Under the same assay conditions, this drug was much more active than Nifurtimox, one of the drugs currently in clinical use to control this disease. This thiocyanate derivative was also a very active inhibitor against the intracellular form of the parasite at the nanomolar level. Other sulfur derivatives prepared also exhibited very potent antiproliferative action against T. cruzi. The presence of a sulfur atom at the polar extreme for this family of compounds seems to be very important for biological action because this atom was always associated to high inhibition values. 4-Phenoxyphenoxyethyl thiocyanate presents very good prospective not only as a lead drug but also as a potential chemotherapeutic agent.