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1.
J Org Chem ; 89(10): 6915-6928, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38687827

RESUMEN

Owing to stereoelectronic effects, lactones often deviate in reactivity from their open-chain ester analogues as demonstrated by the CH acidity (in DMSO) of 3-isochromanone (pKa = 18.8) and 2-coumaranone (pKa = 13.5), which is higher than that of ethyl phenylacetate (pKa = 22.6). We have now characterized the reactivity of the lactone enolates derived from 3-isochromanone and 2-coumaranone by following the kinetics of their Michael reactions with p-quinone methides and arylidenemalonates (reference electrophiles) in DMSO at 20 °C. Evaluation of the experimentally determined second-order rate constants k2 by the Mayr-Patz equation, lg k2 = sN(N + E), furnished the nucleophilicity parameters N (and sN) of the lactone enolates. By localizing their position on the Mayr nucleophilicity scale, the scope of their electrophilic reaction partners becomes predictable, and we demonstrate a novel catalytic methodology for a series of carbon-carbon bond-forming reactions of lactone enolates with chalcones under phase transfer conditions in toluene.

2.
G Ital Nefrol ; 40(5)2023 Oct 26.
Artículo en Italiano | MEDLINE | ID: mdl-38010246

RESUMEN

The abuse of anabolic androgenic steroids (AAS) for competitive (and non-competitive) purposes for bodybuilding practice is increasingly common. The consequences of these substances on the various organs are only partially known. Cases of FSGS following the use of AAS have been reported in the literature, even with evolution to ESKD. We describe three cases of bodybuilding athletes who presented alterations in renal function indices after taking AAS for a long time. Three renal biopsies were performed with histological diagnosis of FSGS collapsing variant. We examine the lesions observed on histological examination. Two athletes had rapid progression of renal disease requiring replacement therapy. The third one continues conservative treatment for chronic renal failure. We discuss the risks related to the intake of doping substances and how bodybuilders are exposed to different causes of kidney damage: anabolic steroids, supplements, and a high-protein diet.


Asunto(s)
Anabolizantes , Glomeruloesclerosis Focal y Segmentaria , Enfermedades Renales , Humanos , Esteroides Anabólicos Androgénicos , Anabolizantes/efectos adversos , Congéneres de la Testosterona/efectos adversos
3.
Biomed Pharmacother ; 168: 115745, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37871561

RESUMEN

Amyloid ß 1-42 (Aß1-42) protein aggregation is considered one of the main triggers of Alzheimer's disease (AD). In this study, we examined the in vitro anti-amyloidogenic activity of the isoindolinone derivative 3-(3-oxoisoindolin-1-yl)pentane-2,4-dione (ISOAC1) and its neuroprotective potential against the Aß1-42 toxicity. By performing the Thioflavin T fluorescence assay, Western blotting analyses, and Circular Dichroism experiments, we found that ISOAC1 was able to reduce the Aß1-42 aggregation and conformational transition towards ß-sheet structures. Interestingly, in silico studies revealed that ISOAC1 was able to bind to both the monomer and a pentameric protofibril of Aß1-42, establishing a hydrophobic interaction with the PHE19 residue of the Aß1-42 KLVFF motif. In vitro analyses on primary cortical neurons showed that ISOAC1 counteracted the increase of intracellular Ca2+ levels and decreased the Aß1-42-induced toxicity, in terms of mitochondrial activity reduction and increase of reactive oxygen species production. In addition, confocal microscopy analyses showed that ISOAC1 was able to reduce the Aß1-42 intraneuronal accumulation. Collectively, our results clearly show that ISOAC1 exerts a neuroprotective effect by reducing the Aß1-42 aggregation and toxicity, hence emerging as a promising compound for the development of new Aß-targeting therapeutic strategies for AD treatment.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Pentanos , Humanos , Enfermedad de Alzheimer/metabolismo , Pentanos/farmacología , Fragmentos de Péptidos/toxicidad , Agregado de Proteínas
5.
G Ital Nefrol ; 40(2)2023 Apr 27.
Artículo en Italiano | MEDLINE | ID: mdl-37179475

RESUMEN

Anti-glomerular basement membrane (anti-GBM) antibody disease is a rapidly progressive glomerulonephritis characterized by (i) positivity to anti-GBM in serum reacting with a specific antigen present in type IV collagen at both the glomerular and alveolar levels (ii) presence of crescent on light microscopy and positivity to linear deposits of IgG and C3 on immunofluorescence. In the classic variant, the clinic is that of a nephro-pneumological syndrome but there are variants. Rarely, the glomerular damage is pauci-immune. We describe a case of a variant in which there is anti-MBG positivity in serum but negative immunofluorescence and offer a review of the literature and potential treatments.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular , Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Humanos , Autoanticuerpos , Glomerulonefritis/complicaciones , Glomerulonefritis/diagnóstico , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/complicaciones , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/diagnóstico , Membrana Basal Glomerular , Enfermedad Aguda , Técnica del Anticuerpo Fluorescente
6.
Int J Mol Sci ; 24(6)2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36982854

RESUMEN

The investigation of the reactivity of an α-amido sulfone derived from 2-formyl benzoate under organocatalytic conditions in the presence of acetylacetone allowed the synthesis of a new heterocyclic hybrid isoindolinone-pyrazole with high enantiomeric excess. Dibenzylamine was also used as a nucleophile to afford an isoindolinone with aminal substituent in 3-position in suitable selectivity. The use of Takemoto's bifunctional organocatalyst not only led to observed enantioselectivity but was also important in accomplishing the cyclization step in both cases. Notably, this catalytic system proved to be particularly effective in comparison to widely used phase transfer catalysts.


Asunto(s)
Pirazoles , Ciclización , Catálisis
7.
RSC Adv ; 13(10): 6557-6563, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36845590

RESUMEN

Herein we report new cascade processes for the easy access to 1-substituted and C-unsubstituted 3-isoquinolinones. The Mannich initiated cascade reaction led to the synthesis of novel 1-substituted 3-isoquinolinones under catalyst-free conditions in the presence of nitromethane and dimethylmalonate as nucleophiles without the use of any solvent. The optimization of the synthesis of the starting material in a more environmentally benign manner, allowed the identification of a common intermediate useful for the synthesis of C-unsubstituted 3-isoquinolinones as well. The synthetic utility of 1-substituted 3-isoquinolinones was also demonstrated.

8.
Acta Med Port ; 36(9): 541-549, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36608696

RESUMEN

INTRODUCTION: Psoriasis is a common, chronic, and inflammatory skin disorder with a high personal, social and economic burden and important implications for healthcare systems. The aim of this study was to provide an epidemiological characterization of individuals with psoriasis in Portugal. MATERIAL AND METHODS: A large observational, cross-sectional, nationwide, population-based survey study developed by the Portuguese Psoriasis Group of the Portuguese Society of Dermatology and Venereology (GPP-SPDV). A structured questionnaire was designed and applied by experienced interviewers to a random, representative sample of Portuguese individuals with psoriasis and/or psoriatic arthritis. Patients were considered to have psoriasis if they replied positively to one of the following questions: "Does any physician have ever diagnosed you with psoriasis?" or "Do you have a skin disorder characterized by scaling, reddish skin lesions located in the elbows/knees/scalp?". RESULTS: A total of 6381 individuals were interviewed, of which 283 met the criteria for psoriasis, corresponding to a prevalence rate of 4.4% (95% CI 3.95 - 4.98). Out of the participants that met psoriasis criteria, 24% had suggestive signs/symptoms but did not have a clinical diagnosis established and were not being monitored by a physician. Although more than 70% of participants had active disease (scaling, erythema, or pruritus) and one third had joint symptoms, only 12% were on systemic treatment. Fifty percent of participants with psoriasis (n = 139) had relevant comorbidities (most frequently depression/anxiety and cardiometabolic diseases). Sixteen percent of participants with psoriasis (n = 46) reported that psoriasis interfered with their daily activities (median impact of 5 in a 0 - 10 scale) and 12% mentioned the disease had an impact in their sexual life (median impact of 5 in a 0 - 10 scale). CONCLUSION: The results of this study suggest that the prevalence rate of psoriasis is likely to be high in Portugal, and several gaps exist at different levels of healthcare delivery to these patients, from diagnosis to treatment. This study provides important data for the future planning of interventions targeting the improvement of psoriasis care in Portugal.


Asunto(s)
Artritis Psoriásica , Psoriasis , Humanos , Portugal/epidemiología , Estudios Transversales , Psoriasis/epidemiología , Psoriasis/tratamiento farmacológico , Artritis Psoriásica/epidemiología , Artritis Psoriásica/diagnóstico , Piel/patología
9.
Int J Mol Sci ; 23(22)2022 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-36430855

RESUMEN

The aim of this review is to give an updated perspective about the methods for chemical modifications of hyaluronic acid (HA) toward the development of new applications in medical devices and material engineering. After a brief introduction on chemical, structural and biological features of this important natural polysaccharide, the most important methods for chemical and physical modifications are disclosed, discussing both on the formation of new covalent bonds and the interaction with other natural polysaccharides. These strategies are of paramount importance in the production of new medical devices and materials with improved properties. In particular, the use of HA in the development of new materials by means of additive manufacturing techniques as electro fluid dynamics, i.e., electrospinning for micro to nanofibres, and three-dimensional bioprinting is also discussed.


Asunto(s)
Materiales Biocompatibles , Bioimpresión , Materiales Biocompatibles/química , Ácido Hialurónico/química , Ingeniería de Tejidos/métodos , Polisacáridos/química
10.
Molecules ; 27(17)2022 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-36080411

RESUMEN

Herein, we report the application of an efficient and practical K2CO3 promoted cascade reaction of 2-acetylbenzonitrile in the synthesis of novel 3-methylated analogs of Pazinaclone and PD172938, belonging to isoindolinones heterocyclic class bearing a tetrasubstituted stereocenter. Organocatalytic asymmetric synthesis of the key intermediate and its transformation into highly enantioenriched 3-methylated analog of (S)-PD172938 was also developed. These achievements can be of particular interest also for medicinal chemistry, since the methyl group is a very useful structural modification in the rational design of new and more effective bioactive compounds.


Asunto(s)
Isoindoles , Ftalimidas , Isoindoles/química , Naftiridinas , Compuestos de Espiro , Estereoisomerismo
11.
J Org Chem ; 87(13): 8420-8428, 2022 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-35699594

RESUMEN

The asymmetric synthesis of novel 3-substituted isoindolinones is herein reported. A new cascade reaction was developed that consisted of the asymmetric nitro-Mannich reaction of suitable α-amido sulfones designed from 2-formyl benzoates, followed by the in situ cyclization of the adducts. Very high enantioselectivities, up to 98% ee, and very good yields were obtained in the presence of the readily available neutral bifunctional organocatalyst derived from trans-1,2-diaminocyclohexane, which is known as Takemoto's catalyst. The investigation of the reactivity of the obtained products allowed either the selective Boc-deprotection or reduction of the nitro group, leading to further functionalized 3-substituted isoindolinones without affecting the enantiomeric purity.


Asunto(s)
Sulfonas , Catálisis , Ciclización , Estructura Molecular , Estereoisomerismo
12.
ACS Omega ; 7(10): 8808-8818, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35309475

RESUMEN

1,4-Conjugate addition of ((chloromethyl)sulfonyl)benzenes to arylideneisoxazol-5-ones, followed by one-pot, N-selective trapping in the presence of electrophiles, was investigated. This strategy led to the synthesis of new, stable N-protected isoxazol-5-ones in good yields and high diastereolectivity. The study of the reactivity of obtained products in the presence of the Mo(CO)6/H2O system allowed the development of a cascade reaction leading to novel methyl ketones in high yields and unchanged dr bearing an uncommon chloromethinearylsulfonyl end group.

13.
Helv Chim Acta ; 105(11): e202200110, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36845268

RESUMEN

We herein report a protocol for the asymmetric aldol-initiated cascade addition of isoxazolidin-5-ones to ortho-cyanobenzaldehydes by using Takemoto's bifunctional organocatalyst. This approach allows for the synthesis of various novel ß2,2-amino acid-phthalide conjugates with good enantio- and diastereoselectivities in reasonable yields and the further ring-opening of these compounds to acyclic carboxylic acid derivatives was demonstrated too.

14.
Molecules ; 26(23)2021 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-34885828

RESUMEN

The properties of mixtures of two polysaccharides, arabinogalactan (AG) and hyaluronic acid (HA), were investigated in solution by the measurement of diffusion coefficients D of water protons by DOSY (Diffusion Ordered SpectroscopY), by the determination of viscosity and by the investigation of the affinity of a small molecule molecular probe versus AG/HA mixtures in the presence of bovine submaxillary mucin (BSM) by 1HNMR spectroscopy. Enhanced mucoadhesive properties, decreased mobility of water and decreased viscosity were observed at the increase of AG/HA ratio and of total concentration of AG. This unusual combination of properties can lead to more effective and long-lasting hydration of certain tissues (inflamed skin, dry eye corneal surface, etc.) and can be useful in the preparation of new formulations of cosmetics and of drug release systems, with the advantage of reducing the viscosity of the solutions.


Asunto(s)
Galactanos/farmacología , Ácido Hialurónico/farmacología , Sales (Química)/química , Sodio/química , Animales , Bovinos , Óxido de Deuterio/química , Diclofenaco/química , Diclofenaco/farmacología , Difusión , Galactanos/química , Ácido Hialurónico/química , Mucinas/química , Espectroscopía de Protones por Resonancia Magnética , Soluciones , Viscosidad , Agua/química
15.
J Org Chem ; 86(21): 15128-15138, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34613731

RESUMEN

Cascade reactions of ortho-carbonyl-substituted benzonitriles with ((chloromethyl)sulfonyl)benzenes as pronucleophiles led to new isoindolin-1-ones with a tetrasubstituted C-3 position or to (Z)-3-(sulfonyl-methylene)isoindolin-1-ones. The reactions start from readily available materials, are carried out under mild conditions, and do not require metal catalysis. Promoted only by the cheap and environmentally benign K2CO3 as the base, up to six elemental steps can be combined in a single pot. Hence, a sequential one-pot cascade/ß-elimination/alkylation furnished useful intermediates for the synthesis of aristolactam natural products. The observed selectivity and the mechanism were investigated by DFT studies.


Asunto(s)
Ciclización , Alquilación , Catálisis
16.
J Org Chem ; 86(15): 10630-10639, 2021 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-34255964

RESUMEN

A highly stereoselective access to 3-sulfinyl-substituted isoindolinones has been achieved by a tandem organocatalytic addition/cyclization reaction of 2-carbobenzyloxy-N-tosylbenzylidenimine with thiols and succeeding diastereoselective oxidation with MCPBA. First, enantioenriched isoindolinone N,S-acetals have been obtained through a dynamic kinetic asymmetric transformation induced by a bifunctional chiral thiourea organocatalyst. In turn, the newly created carbon stereocenter enabled a high diastereocontrol in the subsequent sulfoxidation. Based on DFT calculations, a theoretical rationale for the stereoselectivity of the oxidation reaction is also provided.

17.
Adv Synth Catal ; 363(7): 1955-1962, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33897314

RESUMEN

We herein report the ammonium salt-catalyzed synthesis of chiral 3,3-disubstituted isoindolinones bearing a heteroatom functionality in the 3-position. A broad variety of differently substituted CF3S- and RS-derivatives were obtained with often high enantioselectivities when using Maruoka's bifunctional chiral ammonium salt catalyst. In addition, a first proof-of-concept for the racemic synthesis of the analogous F-containing products was obtained as well, giving access to one of the rare examples of a fairly stable α-F-α-amino acid derivative.

18.
Phytother Res ; 35(1): 486-493, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32785956

RESUMEN

Alzheimer's disease (AD) is a neurodegenerative disorder leading to cognitive deficits and cognitive decline. Since no cure or preventing therapy is currently available to counteract AD, natural-derived compounds are investigated to find new potential neuroprotective agents for its treatment. In the present study, we tested the neuroprotective effect of lavender and coriander essential oils (EOs) and their main active constituent linalool, against the neurotoxicity elicited by Aß1-42 oligomers, a key molecular factor in the neurodegeneration of AD. Importantly, our findings on neuronally differentiated PC12 cells exposed to Aß1-42 oligomers are in accordance with previous in vivo studies reporting the neuroprotective potential of lavender and coriander EOs and linalool. We found that lavender and coriander EOs at the concentration of 10 µg/mL as well as linalool at the same concentration were able to improve viability and to reduce nuclear morphological abnormalities in cells treated with Aß1-42 oligomers for 24 hours. Lavender and coriander EOs and linalool also showed to counteract the increase of intracellular reactive oxygen species production and the activation of the pro-apoptotic enzyme caspase-3 induced by Aß1-42 oligomers. Our findings provide further evidence that these EOs and their main constituent linalool could be natural agents of therapeutic interest against Aß1-42 -induced neurotoxicity.


Asunto(s)
Péptidos beta-Amiloides/toxicidad , Coriandrum/química , Lavandula/química , Fármacos Neuroprotectores/farmacología , Aceites Volátiles/farmacología , Fragmentos de Péptidos/toxicidad , Monoterpenos Acíclicos/farmacología , Enfermedad de Alzheimer , Animales , Trastornos del Conocimiento/inducido químicamente , Disfunción Cognitiva , Células PC12 , Aceites de Plantas/farmacología , Ratas , Especies Reactivas de Oxígeno/metabolismo
19.
Molecules ; 25(10)2020 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-32408552

RESUMEN

In this work we report our endeavors toward the development of an asymmetric synthesis of a 3,3-disubstituted isoindolinone, dimethyl 2-(1-methyl-3-oxoisoindolin-1-yl)malonate, via asymmetric cascade reaction of 2-acetylbenzonitrile with dimethylmalonate and the determination of its absolute configuration (AC) by vibrational circular dichroism (VCD). Bifunctional ammonium salts, derived from trans-1,2-cyclohexanediamine in combination with inorganic bases under phase transfer conditions, were the most effective catalytic systems, leading to the target in high yields and moderate enantioselectivity. An efficient process of heterochiral crystallization allowed the increase of the enantiopurity up to 96% ee and in an acceptable overall yield. An important aim of the present work is the comparison of different VCD methodologies for AC determination of the target compound.


Asunto(s)
Ftalimidas/química , Ftalimidas/síntesis química , Dicroismo Circular , Modelos Moleculares
20.
J Pharm Biomed Anal ; 183: 113152, 2020 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-32088520

RESUMEN

Herein we describe for the first time a practical analytical method for determining the enantio-purity of L-α-glycerophosphocholine (L-α-GPC) by chiral derivatization. The use of a suitable chiral boronic acid allowed the formation of a mixture of two diastereomeric boronate esters whose ratio, carefully analyzed by 1HNMR spectroscopy, reflects L-α-GPC enantiomeric excesses. The determination of the enantiopurity of L-α-GPC furnishes convincing correlations with its manufacturing process.


Asunto(s)
Técnicas de Química Analítica/métodos , Fosforilcolina/química , Ácidos Borónicos/química , Contaminación de Medicamentos , Ésteres/química , Espectroscopía de Resonancia Magnética/métodos , Estereoisomerismo
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