New Chalcogen-Functionalized Naphthoquinones: Design, Synthesis, and Evaluation, In Vitro and In Silico, against Squamous Cell Carcinoma.

Due to the growth in the number of patients and the complexity involved in anticancer therapies, new therapeutic approaches are urgent and necessary. In this context, compounds containing the selenium atom can be employed in developing new medicines due to their potential therapeutic efficacy and unique modes of action. Furthermore, tellurium, a previously unknown element, has emerged as a promising possibility in chalcogen-containing compounds. In this study, 13 target compounds (9a-i, 10a-c, and 11) were effectively synthesized as potential anticancer agents, employing a CuI-catalyzed Csp-chalcogen bond formation procedure. The developed methodology yielded excellent results, ranging from 30 to 85%, and the compounds were carefully characterized. Eight of these compounds showed promise as potential therapeutic drugs due to their high yields and remarkable selectivity against SCC-9 cells (squamous cell carcinoma). Compound 10a, in particular, demonstrated exceptional selectivity, making it an excellent choice for cancer cell targeting while sparing healthy cells. Furthermore, complementing in silico and molecular docking studies shed light on their physical features and putative modes of action. This research highlights the potential of these compounds in anticancer treatments and lays the way for future drug development efforts.

Free radical scavenging activity, determination of phenolic compounds and HPLC-DAD/ESI-MS profile of Campomanesia adamantium leaves.

Numerous diseases are induced by free radicals via lipid peroxidation, protein peroxidation and DNA damage. It has been known that a variety of plant extracts have antioxidant activity to scavenge free radicals. Campomanesia adamantium (Myrtaceae) is a small tree with edible fruit, commonly known as "guavira" or "guabiroba-branca" that has been used in popular medicine as depurative anti-diarrhoeic, antiinflammatory, anti-rheumatic and to liver diseases. In this study, the antiradical activities of ethanol crude extract of the leaves from C. adamantium and the ethyl acetate and butanol fractions obtained by partition, were determined using DPPH (2,2-Diphenyl-1-picrylhydrazyl radical) and ORAC-FL (Oxygen Radical Absorbance Capacity) assays. The total phenol content in the samples was estimated by Folin Ciocalteau method (FCR). In an initial evaluation the ethanolic extract and the fractions ethyl acetate and butanol have shown levels of phenolic compounds between 15- 74 mg GAE/g in FCR assay, showed DPPH free-radical scavenging activity with SC50 in the range of 7.77-13.35 microg/mL and demonstrated antioxidant capacity between 2648-3502 micromol TE/g of extract and fractions in the ORAC-FL assay. HPLC-DAD and ESI-MS analysis revealed were that the extract of the leaves of C. adamantium studied appears to contain flavonoids as major constituents, including isoquercetrin and quercetin that exhibit proven antioxidant activity.

Antioxidant capacity and phenolic content of four Myrtaceae plants of the south of Brazil.

Antioxidant compounds can be useful to prevent several degenerative diseases or as preservative in food and toiletries. Species of the Myrtaceae family are able to accumulate phenolic substances and those are closely related to the antioxidant activity due to their capacity to scavenge free radicals, protect against lipid peroxidation and quench reactive oxygen species. These facts prompted us to investigate the antioxidant capacity of the ethanolic extracts of the leaves of four Myrtaceae plants collected of the south of Brazil: Eugenia chlorophylla O. Berg., Eugenia pyriformis Cambess, Myrcia laruotteana Cambess and Myrcia obtecta (Berg) Kiacrsk. The antioxidant potential was performed using the DPPH (a single electron transfer reaction based assay) and ORAC (Oxygen Radical Absorbance Capacity, a hydrogen atom transfer reaction based assay) assays. Moreover, the total soluble phenolic content was also measured using the Folin-Ciocalteu reagent. A preliminary evaluation of the ethanolic extracts of these Myrtaceae plants revealed high levels of phenolic compounds (343.7-429.3 mg GAE) as well as high antioxidant activity according to both methods (1338 a 3785 micromol of TE/g of extract in ORAC and SC50 in the range of 1.70 and 33.7 microg/mL in the DPPH). The highest antioxidant activity obtained by DPPH assay was exhibited by ethanol extract of the leaves of E. pyriformis (1.70 microg/mL), followed by extracts of M. laruotteana (3.38 microg/mL) and M. obtecta (6.66 microg/mL). In comparison with controls, in the DPPH assay, the extract of E. pyriformis was more active than trolox (SC50 = 2.55 microg/mL), while the extracts of M. laruotteana and M. obtecta were more actives than quercetin (SC50 = 7.80 microg/mL). In the ORAC assay, all species also show good antioxidant capacity (>1000 micromol of TE/g). Initial HPLC-UV/DAD and ESI-MS confirmed the presence of phenolic acids constituents in the ethanol extracts. The results indicate the presence of compounds possessing promising antioxidant/free-radical scavenging activity in the analyzed extracts of Myrcia and Eugenia plants of the south of Brazil.

Essential oils from neotropical Myrtaceae: chemical diversity and biological properties.

Myrtaceae family (121 genera, 3800-5800 spp.) is one of the most important families in tropical forests. They are aromatic trees or shrubs, which frequently produce edible fruits. In the neotropics, ca. 1000 species were found. Several members of this family are used in folk medicine, mainly as an antidiarrheal, antimicrobial, antioxidant, cleanser, antirheumatic, and anti-inflammatory agent and to decrease the blood cholesterol. In addition, some fruits are eaten fresh or used to make juices, liqueurs, and sweets very much appreciated by people. The flavor composition of some fruits belonging to the Myrtaceae family has been extensively studied due to their pleasant and intense aromas. Most of the essential oils of neotropical Myrtaceae analyzed so far are characterized by predominance of sesquiterpenes, some with important biological properties. In the present work, chemical and pharmacological studies carried out on neotropical Myrtaceae species are reviewed, based on original articles published since 1980. The uses in folk medicine and chemotaxonomic importance of secondary metabolites are also briefly discussed.