11th national meeting of organic chemistry and 4th meeting of therapeutic chemistry

This work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e Tecnologia) through project UID/QUI/50006/2013. Fátima Fernandes (SFRH/BPD/98732/2013) and Mariana Barbosa (SFRH/BD/95861/2013) thank FCT for the grants.For the first time under the auspices of Sociedade Portuguesa de Química, the competences of two important fields of Chemistry are brought together into a single event, the 11st National Organic Chemistry Meeting and the the 4th National Medicinal Chemistry Meeting, to highlight complementarities and to promote new synergies. Abstracts of plenary lectures, oral communications, and posters presented during the meeting are collected in this report.publishersversionpublishe

Cholesteryl hemiesters alter lysosome structure and function and induce proinflammatory cytokine production in macrophages

Rationale: Cholesteryl hemiesters are oxidation products of polyunsaturated fatty acid esters of cholesterol. Their oxo-ester precursors have been identified as important components of the "core aldehydes" of human atheromata and in oxidized lipoproteins (Ox-LDL). We had previously shown, for the first time, that a single compound of this family, cholesteryl hemisuccinate (ChS), is sufficient to cause irreversible lysosomal lipid accumulation (lipidosis), and is toxic to macrophages. These features, coupled to others such as inflammation, are typically seen in atherosclerosis. Objective: To obtain insights into the mechanism of cholesteryl hemiester-induced pathological changes in lysosome function and induction of inflammation in vitro and assess their impact in vivo. Methods and results: We have examined the effects of ChS on macrophages (murine cell lines and primary cultures) in detail. Specifically, lysosomal morphology, pH, and proteolytic capacity were examined. Exposure of macrophages to sub-toxic ChS concentrations caused enlargement of the lysosomes, changes in their luminal pH, and accumulation of cargo in them. In primary mouse bone marrow-derived macrophages (BMDM), ChS-exposure increased the secretion of IL-1 beta, TNF-alpha and IL-6. In zebrafish larvae (wild-type All and PU.1:EGFP), fed with a ChS-enriched diet we observed lipid accumulation, myeloid cell-infiltration in their vasculature and decrease in larval survival. Under the same conditions the effects of ChS were more profound than the effects of free cholesterol (FC). Conclusions: Our data strongly suggest that cholesteryl hemiesters are pro-atherogenic lipids able to mimic features of Ox-LDL both in vitro and in vivo.NOVA4Health - UID/Multi/04462/2013, a program financially supported by Fundação para a Ciência e Tecnologia (FCT)/Ministério da Educação e Ciência, through national funds and co-funded by FEDER under the PT2020 Partnership Agreement. FCT fellowship references: SFRH/BPD/26843/2006, SFRH/BD/62126/2009, SFRH/BD/90258/2012, SFRH/BD/84685/2012, SFRH/BPD/102229/2014, SFRH/BD/52293/2013info:eu-repo/semantics/publishedVersio

High Instantaneous Inhibitory Potential of Bictegravir and the New Spiro-β-Lactam BSS-730A for HIV-2 Isolates from RAL-Naïve and RAL-Failing Patients

Funding Information: This work was supported by Fundação para a Ciência e Tecnologia (FCT), Portugal, Aga Khan Development Network (AKDN)–Portugal Collaborative Research Network in Portuguese-speaking countries in Africa (project 332821690). CQC is supported by FCT through projects UIDB/00313/2020 and UIDP/QUI/00313/2020, co-funded by COMPETE2020-UE. iMed.ULisboa, Faculdade de Farmácia da Universidade de Lisboa, Portugal, is supported by FCT through projects UIDB/04138/2020 and UIDP/04138/2020. Inês Bártolo is supported by FCT through Norma Transitória–DL57/2016/CP1376/CT0012. Ana Rita Diniz (SFRH/BD/89140/2012), Francisco Martin (SFRH/BD/87488/2012), Inês Moranguinho (SFRH/BD/131062/2017), and Américo Alves (SFRH/BD/128910/2017) were supported by Ph.D. grants from FCT, Portugal. Publisher Copyright: © 2022 by the authors.Integrase inhibitors (INIs) are an important class of drugs for treating HIV-2 infection, given the limited number of drugs active against this virus. While the clinical efficacy of raltegravir and dolutegravir is well established, the clinical efficacy of bictegravir for treating HIV-2 infected patients has not been determined. Little information is available regarding the activity of bictegravir against HIV-2 isolates from patients failing raltegravir-based therapy. In this study, we examined the phenotypic and matched genotypic susceptibility of HIV-2 primary isolates from raltegravir-naïve and raltegravir-failing patients to raltegravir, dolutegravir, and bictegravir, and to the new spiro-β-lactam BSS-730A. The instantaneous inhibitory potential (IIP) was calculated to help predict the clinical activity of bictegravir and BSS-730A. Isolates from raltegravir-naïve patients were highly sensitive to all INIs and BSS-730A. Combined integrase mutations E92A and Q148K conferred high-level resistance to raltegravir, and E92Q and T97A conferred resistance to raltegravir and dolutegravir. The antiviral activity of bictegravir and BSS-730A was not affected by these mutations. BSS-730A displayed strong antiviral synergism with raltegravir. Mean IIP values at Cmax were similar for all INIs and were not significantly affected by resistance mutations. IIP values were significantly higher for BSS-730A than for INIs. The high IIP values of bictegravir and BSS-730A for raltegravir-naïve and raltegravir-resistant HIV-2 isolates highlight their potential value for treating HIV-2 infection. Overall, the results are consistent with the high clinical efficacy of raltegravir and dolutegravir for HIV-2 infection and suggest a promising clinical profile for bictegravir and BSS-730A.publishersversionpublishe

Synthesis and thermal reactivity of 3-benzyl-7-trifluoromethyl-1H,3H-pyrrolo[1,2-c]thiazole-2,2-dioxide

The generation and reactivity of 1-benzyl-5-trifluoromethyl-azafulvenium methide are described. Under microwave induced pyrolysis this intermediate could be trapped by dipolarophiles acting as a 4π as well as 8π dipole. It was observed that with dimethyl acetylenedicarboxylate the 1,3-dipolar cycloadduct was the major product whereas with N-substituted maleimides the major product results from the addition across the 1,7-position. FMO analysis of the cycloadditions corroborated the rationalization of the observed reactivity. Quantum chemical calculations carried out at the DFT level of theory allowed the rationalization of the stereoselectivity observed in the cycloaddition of 1-benzyl-5-trifluoromethyl-azafulvenium methide with N-substituted maleimides. The study revealed that exo-cycloaddition is the main reaction path for the 1,7-cycloaddition, while the endo-approach is the main mode of reaction leading to 1,3-cycloadducts. In addition, under flash vacuum pyrolysis or conventional thermolysis, 1-benzyl-5-trifluoromethyl-azafulvenium methide undergoes an allowed suprafacial sigmatropic [1,8]H shift leading to the efficient formation of 2-methyl-1-styryl-3-trifluoromethyl-1H-pyrrole.Fil: Peláez, Walter José. Universidad de Coimbra; Portugal. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pinho e Melo, Teresa M.V.D.. Universidad de Coimbra; Portuga

Reactivity of azafulvenium methides derived from pyrrolo[1,2-c]thiazole-2,2-dioxides: synthesis of functionalised pyrroles

Extrusion of sulfur dioxide from pyrrolo[1,2-c]thiazole-2,2-dioxides led to the synthesis of functionalised pyrroles via the generation of 1-azafulvenium methides. Sealed tube reaction conditions allowed the synthesis of N- and C-vinylpyrroles whereas from FVP methyl 1,3-dimethyl-5-oxo-5H-pyrrolizine-2-carboxylate and 4-oxo-1,4-dihydro-1-aza-benzo[f]azulene-3-carboxylates were obtained. These last compounds could also be obtained from the FVP of the N- and C-vinylpyrroles.http://www.sciencedirect.com/science/article/B6THS-4C4DX0X-4/1/eac3571d66ca5b141129aa261f28132

Reactivity of 2-halo-2H-azirines. Part 3: Dehalogenation of 2-halo-2H-azirine-2-carboxylates

The dehalogenation of 2-halo-3-phenyl-2H-azirine-2-carboxylates is described. Using sodium borohydride and tributyltin hydride 3-phenyl-2H-azirine-2-carboxylates were obtained in moderate yields. The synthesis of a new 2-bromo-2H-azirines with a chiral auxiliary, 10-phenylsulfonylisobornyl 2-bromo-3-phenyl-2H-azirine-2-carboxylate, is reported. Its dehalogenation led to 10-phenylsulfonylisobornyl 2H-azirine-2-carboxylate as single stereoisomer together with the formation of 10-phenylsulfonylisobornyl acetate.http://www.sciencedirect.com/science/article/B6THR-482NK06-7/1/b576da25bb07c16918052295f89735c

Cycloaddition of trifluoromethyl azafulvenium methides: synthesis of new trifluoromethylpyrrole-annulated derivatives

The chemistry of trifluoromethyl azafulvenium methides was explored leading to a new route to trifluoromethylpyrrole-annulated systems. The first evidence of azafulvenium methides acting as 1,3-dipoles is reported. These azafulvenium methides showed site selectivity in the reaction with strong electron-deficient dipolarophiles leading exclusively to 1,3-cycloadducts. In the cycloaddition with less-activated dipolarophiles 1,7-cycloadducts resulting from [8π+2π] cycloaddition are also formed. FMO analysis of the cycloaddition reactions allowed the rationalization of the observed selectivity. Graphical abstrac

4-Halo-1,3-oxazoles: Unambiguous structural assignment of 2-halo-2-benzoyl-2H-azirine-3-carboxylates thermal ring expansion products

http://www.sciencedirect.com/science/article/B6TGS-4T9CD1T-2/2/97ced5a20f3a7c031b52a8483cc8ee7