{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T23:13:04Z","timestamp":1790723584674,"version":"4.1.0"},"reference-count":45,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2017,4,4]],"date-time":"2017-04-04T00:00:00Z","timestamp":1491264000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["254321"],"award-info":[{"award-number":["254321"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Departamento de Recursos del Mar-CINVESTAV-IPN","award":["Own resources"],"award-info":[{"award-number":["Own resources"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Parasitic diseases are a public health problem affecting millions of people worldwide. One of the scaffolds used in several drugs for the treatment of parasitic diseases is the benzimidazole moiety, a heterocyclic aromatic compound. This compound is a crucial pharmacophore group and is considered a privileged structure in medicinal chemistry. In this study, the benzimidazole core served as a model for the synthesis of a series of 2-(2-amino-5(6)-nitro-1H-benzimidazol-1-yl)-N-arylacetamides 1\u20138 as benznidazole analogues. The in silico pharmacological results calculated with PASS platform exhibited chemical structures highly similar to known antiprotozoal drugs. Compounds 1\u20138 when evaluated in silico for acute toxicity by oral dosing, were less toxic than benznidazole. The synthesis of compounds 1\u20138 were carried out through reaction of 5(6)-nitro-1H-benzimidazol-2-amine (12) with 2-chlroactemides 10a\u2013h, in the presence of K2CO3 and acetonitrile as solvent, showing an inseparable mixture of two regioisomers with the -NO2 group in position 5 or 6 with chemical yields of 60 to 94%. The prediction of the NMR spectra of molecule 1 coincided with the experimental chemical displacements of the regioisomers. Comparisons between the NMR prediction and the experimental data revealed that the regioisomer endo-1,6-NO2 predominated in the reaction. The in vitro antiparasitic activity of these compounds on intestinal unicellular parasites (Giardia intestinalis and Entamoeba histolytica) and a urogenital tract parasite (Trichomonas vaginalis) were tested. Compound 7 showed an IC50 of 3.95 \u03bcM and was 7 time more active against G. intestinalis than benznidazole. Compounds 7 and 8 showed 4 times more activity against T. vaginalis compared with benznidazole.<\/jats:p>","DOI":"10.3390\/molecules22040579","type":"journal-article","created":{"date-parts":[[2017,4,4]],"date-time":"2017-04-04T10:15:12Z","timestamp":1491300912000},"page":"579","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":13,"title":["Design, Synthesis and Biological Evaluation of 2-(2-Amino-5(6)-nitro-1H-benzimidazol-1-yl)-N-arylacetamides as Antiprotozoal Agents"],"prefix":"10.3390","volume":"22","author":[{"given":"Emanuel","family":"Hern\u00e1ndez-N\u00fa\u00f1ez","sequence":"first","affiliation":[{"name":"CONACYT, Departamento de Recursos del Mar, Centro de Investigaci\u00f3n y de Estudios Avanzados del IPN, Unidad M\u00e9rida, M\u00e9rida 97310, Yucat\u00e1n, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hugo","family":"Tlahuext","sequence":"additional","affiliation":[{"name":"Centro de Investigaciones Qu\u00edmicas, Universidad Aut\u00f3noma del Estado de Morelos, Cuernavaca 62210, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rosa","family":"Moo-Puc","sequence":"additional","affiliation":[{"name":"Unidad Interinstitucional de Investigaci\u00f3n M\u00e9dica, Instituto Mexicano del Seguro Social\/Universidad Aut\u00f3noma de Yucat\u00e1n, M\u00e9rida 97150, Yucat\u00e1n, M\u00e9xico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diego","family":"Moreno","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda, Universidad Aut\u00f3noma de Yucat\u00e1n, M\u00e9rida 97310, Yucat\u00e1n, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Ortencia","family":"Gonz\u00e1lez-D\u00edaz","sequence":"additional","affiliation":[{"name":"CONACYT, Centro de Investigaci\u00f3n Cient\u00edfica de Yucat\u00e1n, M\u00e9rida 97200, Yucat\u00e1n, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5344-4762","authenticated-orcid":false,"given":"Gabriel Navarrete","family":"V\u00e1zquez","sequence":"additional","affiliation":[{"name":"Facultad de Farmacia, Universidad Aut\u00f3noma del Estado de Morelos, Cuernavaca 62209, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2017,4,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1016\/j.ijpara.2015.01.011","article-title":"Unconventional actins and actin-binding proteins in human protozoan parasites","volume":"45","author":"Gupta","year":"2015","journal-title":"Int. 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