We describe our results for the synthesis of 2′-(1,2,3-triazoyl)-acetophenones by copper catalyzed azide–alkyne cycloaddition of 2′-azidoacetophenone with alkynes. The corresponding 2′-(1,2,3-triazoyl)-acetophenones were obtained in moderate to excellent yields and according to our experiments, it was observed that ultrasound accelerates the reaction compared to conventional heating. In addition, the obtained compounds were screened by molecular docking for their possible inhibitory effect on the activity of monoamine oxidase (MAO), an enzyme responsible for the degradation of monoamine neurotransmitters. Three compounds were selected and presented an inhibitory effect on both MAO-A and B isoform activities in vitro. These new MAO inhibitors may be of interest to treat monoamine deficit related-neuropsychiatric disorders, such as depression and Parkinson's disease.

We describe here our results from the copper-catalyzed three component reaction of 2-azidobenzaldehyde, anthranilamide and terminal alkynes, using Et₃N as base, and DMSO as solvent. Depending on the temperature and amount of Et₃N used in the reactions, 1,2,3-triazolyl-quinazolinones or 1,2,3-triazolyl-dihydroquinazolinone could be obtained. When the reactions were performed at 100 °C using 2 equivalents of Et₃N, 1,2,3-triazolyl-dihydroquinazolinone was formed in 82% yield, whereas reactions carried out at 120 °C using 1 equivalent of Et₃N provided 1,2,3-triazolyl-quinazolinones in moderate-to-good yields.

Carbon–carbon and carbon-heteroatom bond forming reactions are strategically employed for the generation of a variety of heterocyclic systems. This class of compounds represents the most general structural unit, present in many natural compounds. They are recognized for their valuable biologically properties and wide range of applications in medicinal, pharmaceutical, and other related fields of chemistry. This is an updated review on the use of dicarbonyl compounds under environmentally friendly conditions to access a series of heterocyclic structures, e.g., quinoxaline, quinazolinones, benzochalcogenazoles, indoles, among others. Synthetic protocols involving copper-catalyzed, multicomponent and cascade reactions, decarboxylative cyclization, recycling of CO₂, and electrochemical approaches are presented and discussed.

Here we describe the functionalization of lupulone natural compound in obtaining 3-isobutyl-5,5,7-tris(3-methylbut-2-en-1-yl)-1-phenyl-1,7-dihydro-4H-indazole-4,6(5H)-dione. The lupulone-H-indazole derivative was prepared with 75% yield through the reaction between lupulone and phenyl-hydrazine employing SiO₂/ZnCl₂ (30% m/m) as a support solid in a solvent-free condition. Based on the possibilities of products, a complete NMR structural characterization of this lupulone-H-indazole was performed by ¹H, ¹³C{¹H}, COSY, HSQC and HMBC NMR experiments, showing an important contribution in producing the first results related to lupulone reactivity.