(2E)-2-(2,4-Dichloro­phenyl­sulfon­yl)-3-(4-methyl­anilino)-3-(methyl­sulfan­yl)acrylonitrile

The title compound, C17H14Cl2N2O2S2, and the 3-methoxy­anilino analogue reported in the preceding paper have been used as starting materials to develop benzothia­zine derivatives with anti­malarial activity. The mol­ecule displays an E (trans) configuration about the central double bond. Due to conjugation in the C=C—C N group, the putative single bond shows a significant shortening [1.418 (3) Å]. The mol­ecule has a six-membered ring involving an intra­molecular N—H⋯O(sulfon­yl) bond, which is an example of resonance-assisted hydrogen bonding. In the crystal structure, bonds of the C—H⋯O(sulfon­yl) and C—H⋯N(cyano) types form double layers of mol­ecules parallel to (01). Within these layers there are π–π inter­actions between benzene rings of pairs of centrosymmetrically related mol­ecules, with distances of 3.7969 (12) Å between centroids. C—H⋯π interactions are also present

Synthesis, antimalarial activity, structure–activity relationship analysis of thieno-[3,2-b]benzothiazine S,S-dioxide analogs

An improved procedure for the synthesis of 3-amino-9-arylsubstituted-thieno[3,2-b]benzothiazine S,S-dioxide 2-decarboxylated is reported. Thieno-[3,2-b]benzothiazine S,S-dioxide derivatives were investigated for their abilities to inhibit β-hematin formation, hemoglobin hydrolysis and in vivo for their efficacy in rodent Plasmodium berghei. Compounds 5j-o were the most promising as inhibitors of hemoglobin hydrolysis, however, the compounds are not as efficient as chloroquine. A structure-activity relationship (SAR) study was carried out in this series. Our results allow us to determine the minimal structural requirements to produce the biological response.Fil: Barazarte, Arthur. Universidad Central de Venezuela; VenezuelaFil: Camacho, José. Universidad Central de Venezuela; VenezuelaFil: Domínguez, José. Universidad Central de Venezuela; VenezuelaFil: Lobo, Gricela. Universidad Central de Venezuela; VenezuelaFil: Gamboa, Neira. Universidad Central de Venezuela; VenezuelaFil: Rodrigues, Juan. Universidad Central de Venezuela; VenezuelaFil: Capparelli, Mario V.. Universidad Central de Venezuela; VenezuelaFil: Álvarez Larena, Ángel. Universitat Autònoma de Barcelona; EspañaFil: Andujar, Sebastian Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Enriz, Ricardo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Instituto Multidisciplinario de Investigaciones Biológicas de San Luis; ArgentinaFil: Charris, Jaime. Universidad Central de Venezuela; Venezuel

Synthesis and biological evaluation of benzothiazole-6-carbohydrazide derivatives as antiparasitic agents

A series of N´-substituted-2-(5-nitrofuran or 5-nitrothiophen-2-yl)-3h-benzo[d]thiazole-6-carbohydrazide derivatives were synthesized and investigated for their abilities to inhibit B-hematin formation, hemoglobin proteolysis and for their antimalarial efficacy in rodent Plasmodium berghei. Moreover, we investigated the effect on the viability of Trypanosoma cruzi and Leishmania braziliensis in vitro. We performed a scan to evaluate the cytotoxic effects against two non tumourogenic cell lines. We found that compounds 5a, 6a, and 6g were the most promising as inhibitors of B-hematin formation, especial attention should be paid to 6a which also inhibited hemoglobin proteolysis moderately, decreased parasitaemia and prolonged survivals in infected-mice significantly compared to vehicle controls. Finally, we demonstrated that the compound 7f have a profound effect on the viability of T. cruzi (Tulahuen, CL Brener), shown an IC50 values of 7.7 μm and 0.2 μm respectively, without affecting the viability of the host cells. All compounds showed a marginal activity against L. braziliensis. Thus, compounds 6a and 7f showed anti-parasitic efficacy and good safety inde