Resumo Na química medicinal, esforços extensivos de pesquisa são continuamente direcionados para a descoberta de novos heterociclos com efeitos farmacológicos apropriados. Especificamente, o papel dos derivados de pirazol na química medicinal é vital devido à sua ampla gama de atividades biológicas. Devido a esta notável observação, esta revisão é desenvolvida com foco nos avanços dos procedimentos sintéticos ecologicamente corretos em termos de rendimento, curto tempo de reação e condições de limpeza na obtenção de 2-pirazolinas, com base em uma análise bibliográfica de pesquisas que tomam como referenciar os anos de 2019 a 2021 no que diz respeito à obtenção destes sistemas em condições simplificadas e energeticamente sustentáveis.

Abstract In medicinal chemistry, extensive research efforts are continuously directed towards the discovery of new heterocycles with appropriate pharmacological effects. Specifically, the role of pyrazole derivatives in medical chemistry is vital, given its wide range of biological activities. In light of this notable observation, this review is carried out with a focus on advances in eco-friendly synthetic procedures in terms of performance, short reaction time, and clean conditions when obtaining 2-pyrazolines, based on a bibliographic analysis of research that takes the years 2019 to 2021 as a reference with regard to obtaining these systems in simplified and energy-sustainable conditions.

Resumen En química medicinal, se dirigen continuamente extensos esfuerzos en investigación al descubrimiento de nuevos heterociclos con efectos farmacológicos apropiados. Específicamente, el papel de los derivados del pirazol en la química médica es vital debido a su amplia gama de actividades biológicas. Por esta notable observación, se desarrolla esta revisión con enfoque sobre los avances de procedimientos sintéticos eco-amigables en términos de rendimiento, tiempo de reacción corto y condiciones limpias en la obtención de 2-pirazolinas, a partir de un análisis bibliográfico de investigación que toma como referencia los años 2019 a 2021 con respecto a la obtención de estos sistemas en condiciones simplificadas y energéticamente sustentables.

The pyrazole core has been recognized by their biological properties and included in the synthesis of modern agrochemicals. Part of these studies consists of making structural modifications to pesticides for commercial purposes to increase efficacy. In this article, we present the synthesis of four new pyrazol-4-carboxamide 8a-8d derivatives (PCD), through a four-step synthetic protocol, starting with edaravone 1 and primary amines like benzo-fused, aliphatic, and hydrazines, through a process of low environmental impact. Synthesized derivatives were evaluated against one fungal strain of Colletotrichum gloeosporioides BA3, fungus that causes several losses to farmers around the world, through in vitro sensitivity tests. The compound 8c showed better inhibiting behavior against Colletotrichum gloeosporioides BA3, inducing a lag phase of almost 2.77 days. These results were obtained via Gompertz modeling, for the first time reported for biological evaluation of pyrazole-carboxamide derivatives against Colletotrichum gloeosporioides.

Abstract Theoretical and experimental evaluation of people´s exposure to electromagnetic radiation due to base stations of mobile telephony located in the city of Soledad, Atlántico (Colombia) was carried out. This was done by calculating the radiation intensity of the antennas and the distance of the exposed person. Experimentally, power density measurements were done at 22 base stations using a broadband radio frequency measurement equipment. A limited set of measured power density values were compared and discussed with the calculated values. The results show that the power density values in each mobile telephone base station are well below the permissible limits to electromagnetic fields in the Colombian and international regulations, 4.5 W/m2 and 9.0 W/m2 for frequencies of 900 MHz and 1800 MHz, respectively.

Resumen Se realizó una evaluación teórica y experimental de la exposición poblacional a la radiación electromagnética debida a estaciones base de telefonía móvil ubicadas en el municipio de Soledad, Atlántico (Colombia). Esto se realizó mediante el cálculo de la intensidad de radiación de las antenas y la distancia de la persona expuesta. Experimentalmente, se realizaron mediciones de densidad de potencia en 22 estaciones base usando un equipo de medición de radiofrecuencia de banda ancha. Un conjunto limitado de valores de densidad de potencia medido fue comparado y discutido con los valores calculados. Los resultados demuestran que los valores de densidad de potencia en las estaciones base de telefonía móvil se encuentran muy por debajo de los límites permisibles a los campos electromagnéticos de la normatividad colombiana e internacional, 4.5 W/m2 y 9.0 W/m2 para frecuencias de 900 MHz y 1800 MHz, respectivamente.

5-Aryl-3-(2-methoxynaphthalen-6-yl)-1-phenylpyrazoline derivatives were synthesized starting from (E)-1-(3-aryl)-(2-methoxynaphthalen-6-yl)-prop-2-en-1-one and phenylhydrazine. The compounds were characterized by 1H and 13C nuclear magnetic resonance (NMR), elemental analyses and mass spectrometry. Some compounds showed promising luminescence properties in solution and in solid state; the absorption and emission characteristics were measured and the fluorescence quantum yield of two of the derivatives [4,5-dihydro-3-(2-methoxynaphthalen-6-yl)-5-(3,4,5-trimethoxyphenyl)-1-phenyl-1 H -pyrazoline and 5-(4-chlorophenyl)-4,5-dihydro-3-(2-methoxynaphthalen-6-yl)-1-phenyl-1 H -pyrazoline] were found to have excellent values compared to rhodamine B standard. Theoretical calculations at time-dependent density functional theory (TD-DFT) level are in agreement with the experimental measurements and are helpful to explain the electronic behavior.

A atividade leishmanicida de uma série de derivados enônicos (chalconas) sintetizados via reações de condensação de Claisen-Schmidt assistidas por radiação ultrassom foi caracterizada através da análise de suas citotoxicidades contra formas promastigotas de Leishmania (Viannia) panamensis, espécie responsável por mais de 90% dos casos de Leishmania na Colômbia. Dois compostos foram ativos contra Leishmania com índices de seletividade de LC50 EC50-1 (concentração letal média e concentração efetiva média) maiores que 27 e 3, respectivamente. Estes resultados sugerem que a substituição de um dos dois anéis de chalcona (anel A aromático) com oxigênio é apropriada. Um composto deve ser pesquisado quanto à sua atividade leishmanicida, especialmente por ser fácil de obter em elevados rendimentos, tornando possível a produção de medicamentos para o tratamento de leishmaniose cutânea.

The antileishmanial activity of a series of enonic derivatives (chalcones) synthesized via Claisen-Schmidt condensation reactions assisted by ultrasonic radiation was characterized by analyzing their cytotoxicity against Leishmania (Viannia) panamensis promastigotes, a species responsible for over 90% of Leishmania cases in Colombia. Two compounds were active against Leishmania with selectivity indexes of LC50 EC50-1 (lethal concentration 50 and effective concentration 50) higher than 27 and 3, respectively. These results suggest that a substitution on one of the two chalcone rings (aromatic ring A) with oxygen is convenient. Compound 3g should be further investigated for its antileishmanial activity, especially for being easy to obtain in high yields, making it possible to produce drugs for the treatment of cutaneous leishmaniasis.

Uma série de (E)-2-(benzo[d]tiazol-2-il)-3-arilacrilonitrilas foi sintetizada pela condensação de Knoevenagel assistida por microondas, na ausência de solvente, partindo do correspondente 2-(benzo[d]tiazo-2-il)acetonitrila e aldeídos aromáticos, contendo tanto grupos doadores de elétrons, como retiradores. Os tempos de reação foram consideravelmente curtos e os produtos, obtidos em rendimentos moderados (50-75%) e boa pureza. A configuração da dupla ligação da acrilonitrila não pôde ser estabelecida por métodos comuns de RMN. No entanto, estudos teóricos sugerem que nesses compostos o isômero E é mais estável do que o Z, o que está de acordo com algumas evidências experimentais.

A series of (E)-2-(benzo[d]thiazol-2-yl)-3-arylacrylonitriles was synthesized by microwave assisted Knoevenagel condensation under solvent-free conditions from the corresponding 2-(benzo[d]thiazol-2-yl)acetonitrile and aromatic aldehydes with electrondonating/electron-withdrawing groups. The reaction times were considerably short and the products obtained in moderate yields (50 to 75%) and good purity. The configuration of the acrylonitrile double bond could not be established by regular NMR methods. However, theoretical studies suggest that the E isomer is more stable than Z, which is in good agreement with some experimental evidences.