BACKGROUND Only benznidazole (Bnz) (1) and nifurtimox (Nfx) (2) are licensed for the treatment of Chagas disease although their safety and efficacy profile are far from ideal. Farmanguinhos from Fiocruz has developed seven nitroimidazole compounds (4-10) analogs of megazol (3). OBJECTIVES To evaluate whether the genotoxic effect of 3 was abolished in the seven nitroimidazoles (4-10) analogs using the in vitro alkaline comet assay (CA) and the in vitro cytokinesis-block micronucleus assay (CBMN) in whole human blood cells (WHBC) and correlate this effect with their trypanocidal activity using bloodstream trypomastigote forms of Trypanosoma cruzi. METHODS The toxicity of 3-10 to WHBC in the in vitro CA was determined using the fluorescein diacetate/ethidium bromide assay. DNA damage in the in vitro CA was evaluated according to tail size in four classes (0-3) and methyl methane-sulfonate (MMS) was used as a positive control. The cytotoxicity of 3-10 to WHBC in the CBMN was measured using the cytokinesis-block proliferation index and the replication index. The number of the micronucleate cells in 2,000 binucleate cells by experimental group was determined. Mitomycin C and N-deacetyl-N-methylcolchicine were used as positive controls. FINDINGS Compound 3 showed a significant DNA strand break effect through the in vitro CA and highly significant clastogenic and/or aneugenic effect in the CBMN. Compounds 5, 6, 8, 9 and 10 showed negative results in the CBMN and positive results in the in vitro CA, while the inverse effect was observed for 4 and 7. MAIN CONCLUSIONS Compound 10 was the most promising to proceed with the development as a drug candidate in the treatment of Chagas disease showing absence of chromosomal cytogenetic damage and high activity against T. cruzi, about two times higher than 3 and the clinical drug 1.

The chronic myeloid leukemia (CML) is characterized by presence of the Philadelphia chromosome (Ph), originated from the translocation between chromosomes 9 and 22. This chromosome generates an abnormal protein tyrosine kinase which is responsible for tumor cell proliferation. The emergence of tyrosine kinase inhibitors (TKIs) has transformed the treatment of CML and imatinib being the first representative of this class. Although treatment with imatinib has reached surprising results, approximately 30% of patients exhibited resistance, especially in later stages of the disease. This fact stimulated the development of novel BCR-ABL enzyme inhibitors drugs classified as tyrosine kinase inhibitors (TKIs) of second and third generations. The TKIs have different chemical functions in their structure, and the knowledge of synthetic methods for preparation of these compounds can be a powerful tool for the development of new derivatives. The five approved BCR-ABL Tyrosine Kinase inhibitors (TKI) used in Chronic Myeloid Leukemia (CML) are reviewed aiming the main synthetic routes, highlighting the advantages and disadvantages associated with them.

Presently, the world depends on a wide variety of new materials based on organofluorine compounds. These compounds can be used as surfactants, high resistance polymers, liquid crystals, agrochemicals, radiopharmaceuticals for positron emission tomography, and drugs. However, the selective formation of C–F bonds remains a challenge. This study reviews our knowledge of organofluorine compounds and describes conventional and modern selective fluorination methods for obtaining these compounds. Here, we highlight the most common fluorination reagents and describe the fluorination reactions. This review is organized by the type of fluorine transfer: nucleophilic, electrophilic, and enzymatic

Nuclear magnetic resonance is a technique that is widely used for elucidating and characterizing organic substances. Organofluorine substances have applications in many areas from drugs to liquid crystals, but their NMR spectra are often challenging due to fluoride coupling with other nuclei. For this reason, NMR spectra of this class of substances are not commonly covered in undergraduate and graduate chemistry courses and related fields. Thus, the aim of this work was the presentation and discussion of 1H, 13C, and 19F NMR spectra of eleven organofluorine substances which, in the case of 1H and 13C nuclei, showed classic patterns of first-order coupling and the effects of the fluorine nucleus in different chemical and magnetic environments. In addition, the observation of long distance coupling constants was possible through the use of apodization functions in the processing of the spectra. It is expected that the examples presented herein can be utilized and discussed in undergraduate and graduate NMR spectroscopy disciplines and thus improve the teaching and future research of organofluorine compounds.

Nitroimidazoles exhibit high microbicidal activity, but mutagenic, genotoxic and cytotoxic properties have been attributed to the presence of the nitro group. However, we synthesised nitroimidazoles with activity against the trypomastigotes of Trypanosoma cruzi, but that were not genotoxic. Herein, nitroimidazoles (11-19) bearing different substituent groups were investigated for their potential induction of genotoxicity (comet assay) and mutagenicity (Salmonella/Microsome assay) and the correlations of these effects with their trypanocidal effect and with megazol were investigated. The compounds were designed to analyse the role played by the position of the nitro group in the imidazole nucleus (C-4 or C-5) and the presence of oxidisable groups at N-1 as an anion receptor group and the role of a methyl group at C-2. Nitroimidazoles bearing NO2 at C-4 and CH3 at C-2 were not genotoxic compared to those bearing NO2 at C-5. However, when there was a CH3 at C-2, the position of the NO2 group had no influence on the genotoxic activity. Fluorinated compounds exhibited higher genotoxicity regardless of the presence of CH3 at C-2 or NO2 at C-4 or C-5. However, in compounds 11 (2-CH3; 4-NO2; N-CH2OHCH2Cl) and 12 (2-CH3; 4-NO2; N-CH2OHCH2F), the fluorine atom had no influence on genotoxicity. This study contributes to the future search for new and safer prototypes and provide.

Megazol (7) is a 5-nitroimidazole that is highly active against Trypanosoma cruzi and Trypanosoma brucei, as well as drug-resistant forms of trypanosomiasis. Compound 7 is not used clinically due to its mutagenic and genotoxic properties, but has been largely used as a lead compound. Here, we compared the activity of 7 with its 4H-1,2,4-triazole bioisostere (8) in bloodstream forms of T. brucei and T. cruzi and evaluated their activation by T. brucei type I nitroreductase (TbNTR) enzyme. We also analysed the cytotoxic and genotoxic effects of these compounds in whole human blood using Comet and fluorescein diacetate/ethidium bromide assays. Although the only difference between 7 and 8 is the substitution of sulphur (in the thiadiazole in 7) for nitrogen (in the triazole in 8), the results indicated that 8 had poorer antiparasitic activity than 7 and was not genotoxic, whereas 7 presented this effect. The determination of Vmax indicated that although 8 was metabolised more rapidly than 7, it bounds to the TbNTR with better affinity, resulting in equivalent kcat/KM values. Docking assays of 7 and 8 performed within the active site of a homology model of the TbNTR indicating that 8 had greater affinity than 7.

History shows that public health actions to combat epidemics are most effective when there is constant synergy of both government and society, exemplified by prevention actions in the fight against dengue fever, H1N1 influenza etc. Private-public-partnerships (PPP) can also provide more dynamic and consistent results in production through interaction among Government, University and Enterprise actors. This article puts forward proposals to tackle the problem of neglected tropical diseases via the formation of a Management Council using Etzkowitz's Triple Helix concept to attenuate this public health issue in Brazil.

The leishmanicidal activity of four batches of meglumine antimoniate, produced in Farmanguinhos-Fiocruz, Brazil (TAMs), was assessed and compared to Glucantime®-Aventis Pharma Ltda. Using the amastigote-like in vitro model, the active concentrations of Sb v varied from 10µg/ml to 300 µg/ml for L. (L.) chagasi and from 50µg/ml to 300µg/ml for L. (L.) amazonensis, with no statistically significant differences among the four batches of TAMs and Glucantime®. The inhibitory concentrations (IC50) determined by the amastigote-infected macrophage model for TAM01/03 and Glucantime® were, respectively: 26.3µg/ml and 127.6µg/ml for L. chagasi, 15.4µg /ml and 22.9µg/ml for L. amazonensis, and 12.1µg/ml and 24.2µg/ml for L. (V.) braziliensis. The activities of the four batches of TAMs were confirmed in an in vivo model by assessing, during eight weeks skin lesions caused by L. braziliensis in hamster that were treated with 20mg Sb v/Kg/day for 30 consecutive days. The meglumine antimoniate produced by Farmanguinhos was as effective as the reference drug, Glucantime®-Aventis, against three species of Leishmania that are of medical importance in Brazil.

Este trabalho descreve a versatilidade sintética dos derivados N-Acil-3,3-diflúor-2-oxoindóis, obtidos a partir da reação de N-acilisatinas com dietilaminotrifluoreto de enxofre (DAST) que, através da reação com diferentes nucleófilos, promovem a abertura do anel heterocíclico, levando à formação de vários produtos. A reação de N-Acil-3,3-diflúor-2-oxoindóis com água fornece os ácidos 2-(2-N-acilfenil)-2,2-difluoracéticos e com álcoóis fornece os ésteres correspondentes. Reações com aminas e glicina levam à formação das correspondentes amidas 2-(2-N-acilfenil)-2,2-difluoracetamidas. Na reação com tiossemicarbazidas os derivados difluortiossemicarbazidas são obtidos. Estes últimos sofrem uma ciclização catalisada por ácido para fornecer N-(2-((5-aminoaril-1,3,4-tiadiazol-2-il)difluormetil)-4-(R)-fenil)acetamida. A estrutura de N-(2-((5-amino-1,3,4-tiadiazol-2-il)difluormetil)-4-metilfenil)acetamida foi determinada por raio-X.

This paper describes the versatility of N-Acyl-3,3-difluoro-2-oxoindoles, obtained from the the reaction of N-acylisatins with (diethylamino)sulphur trifluoride (DAST) which, on opening of the heterocyclic ring by reactions with nucleophiles, lead to the formation of a variety of products: reaction with water yields 2-(2-amidoacyl)-2,2-difluoroacetic acids, with alcohols yields alkyl 2-(2-amidoacyl)-2,2-difluoroacetates, with amines and glycine yields 2-(2-amidoacyl)-2,2-difluoroacetamides and with thiosemicarbazides yields difluorothiosemicarbazide derivatives. The latter undergo acid-catalysed cyclizations to yield N-(2-((5-aminoaryl-1,3,4-thiadiazol-2-yl)difluoromethyl)-4-(R)-phenyl)acetamide. The X-ray structure of N-(2-((5-amino-1,3,4-thiadiazol-2-yl)difluoromethyl)-4-methylphenyl)acetamide has been determined.

Neste trabalho investigou-se a reação entre fluoreto de tetrametilamônio seco (TMAF) e 1-metil-2,4,5-tribromoimidazol em diferentes solventes apróticos polares. Nas reações feitas em DMSO, N,N-dimetilacetamida e N-metilpirrolidona, os principais produtos foram provenientes da desbrominação redutiva e não da fluoração, como esperado, mostrando que o TMAF é fortemente básico nestas condições. A reação feita em DMSO deuterado mostrou que o solvente é a principal fonte de próton. A dimetilformamida foi o solvente menos efetivo como doador de prótons, mas forneceu um rendimento significativo do produto fluorado 4,5-dibromo-2-flúor-1-metilimidazol.

The reaction of dry tetramethylammonium fluoride (TMAF) with 1-methyl-2,4,5-tribromoimidazole in different polar aprotic solvents was investigated. Products of reductive debromination were obtained rather than fluorine substitution, indicating that TMAF is strongly basic in such conditions. A reaction carried out in d6-DMSO showed that the solvent is the proton source. Dimethylformamide was less effective that DMSO, N,N-dimethylacetamide or N-methylpirrolidone as a proton donor and we were able to effect significant fluorination in this solvent.