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1.
Front Public Health ; 12: 1328544, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38450126

RESUMO

Background: This study examined access to technology, internet usage, and online health information-seeking behaviors, in a racially diverse, lower-income population. Methods: Data were obtained via a cross-sectional survey of low-income communities in Houston, Los Angeles, and New York between April and August 2023. Binary responses to the following online health information-seeking behaviors, internet and technology access, were examined: using the internet to (i) understand a medical diagnosis, (ii) fill a prescription, (iii) schedule a healthcare appointment, (iv) email communication with a healthcare provider, and (v) access electronic health records and medical notes. Results: 41% of survey respondents identified as non-Hispanic Black individuals, 33% as non-Hispanic White individuals, and 22% as Hispanic individuals. 69% reported a pre-tax annual household income of less than $35,000. 97% reported ownership/access to a smart device; 97% reported access to reliable internet. In the past year, only 59% reported using the internet to better understand their medical diagnosis, 36% reported filling a prescription online, 47% scheduled a medical appointment online, 47% viewed electronic health records online, and 56% emailed healthcare providers. Female sex, higher incomes, and having at least a bachelor's degree were significantly associated with all five online health information-seeking attributes. Conclusion: Despite high technology adoption rates, we observed suboptimal online health information-seeking behaviors. This underutilization has potential adverse implications for healthcare access and use given the documented advantage of HIT. Efforts to increase health information-seeking behaviors should explore the identification of HIT barriers, and patient education to increase familiarity and usage in this population.


Assuntos
Comportamento de Busca de Informação , Uso da Internet , Humanos , Feminino , Estudos Transversais , Internet , Renda
2.
Chemistry ; 30(9): e202303179, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38078727

RESUMO

Herein, we disclose a facile and efficient electrochemical method for the dibromination of aryl amines by double functionalization of aromatic C(sp2 )-H (both para and ortho) under metal- and external oxidant-free conditions at room temperature for the first time. The reaction is demonstrated using 1,2-dibromoethane to dibrominate a wide range of N-substituted aryl amines in a simple setup with C(+)/Pt(-) electrodes under mild reaction conditions. This transformation proceeds smoothly with a broad substrate scope affording the valuable and versatile N-substituted 2,4-dibromoanilines in moderate to excellent yields with high regioselectivity. In this paired electrolysis, cathodic reduction of 1,2-DBE followed by anodic oxidation generates bromonium intermediates, which then couple with anilines to furnish the dibrominated products. It represents a distinctive approach to challenging redox-neutral reactions. The versatility of the electrochemical ortho-, para-dibromination was reflected by unique regioselectivities for challenging aryl amines and gram-scale electrosynthesis without the use of a stoichiometric oxidant or an activating agent.

3.
Gerontol Geriatr Med ; 9: 23337214231201204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781643

RESUMO

Social isolation is a well-documented contributor to poor mental and physical health, and interventions promoting social connectedness have been associated with various health benefits. This study examined predictors of participation in a telephone-based social connectedness intervention for socially isolated older adults. Data were obtained from a social-connectedness intervention that paired college students with Houston-area, community-dwelling adults aged 65 years and older and enrolled in Medicare Advantage plans. We combined machine learning and regression techniques to identify significant predictors of program participation. The following machine-learning methods were implemented: (1) k-nearest neighbors, (2) decision tree and ensembles of decision trees, (3) gradient-boosted decision tree, and (4) random forest. The primary outcome was a binary flag indicating participation in the telephone-based social-connectedness intervention. The most predictive variables in the ML models, with scores corresponding to the 90th percentile or greater, were included in the regression analysis. The predictive ability of each model showed high discriminative power, with test accuracies greater than 95%. Our findings suggest that telephone-based social-connectedness interventions appeal to individuals with disabilities, depression, arthritis, and higher risk scores. scores. Recognizing features that predict participation in social-connectedness programs is the first step to increasing reach and fostering patient engagement.

4.
Chem Commun (Camb) ; 59(53): 8254-8257, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37313773

RESUMO

The first asymmetric total synthesis of (+)-propolisbenzofuran B is accomplished in 11 steps with an overall yield of 11.9%. The key steps are tandem deacetylative Sonogashira coupling-annulation reaction to synthesize the 2-substituted benzofuran core, stereoselective syn-aldol reaction and Friedel-Crafts cyclization to install the desired stereocenters & third-ring, and Stille coupling for C-acetylation.


Assuntos
Estereoisomerismo , Ciclização
5.
Org Biomol Chem ; 21(20): 4195-4199, 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37132431

RESUMO

A one-pot electronically controlled [4 + 2] cycloaddition reaction of in situ generated benzyne with 2-arylidene-1-indenone is unveiled to construct novel spirocyclic frameworks in a regio- and diastereoselective fashion. This protocol features operational simplicity, good functional group tolerance and avoids the use of metal catalysts and external additives. This methodology has extended the synthetic application of 2-arylidene-1-indenones enabling easy access to valuable 10'H-spiro[indene-2,9'-phenanthren]-1(3H)-ones in good yields.

6.
Org Lett ; 25(13): 2258-2263, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-36966396

RESUMO

An operationally simple and efficient domino etiquette has been developed for the facile construction of 1,2-dithioles employing easily accessible dithioesters as a three-atom CCS synthon and aryl isothiocyanates as a two-atom CS unit in the absence of any catalyst and additive at room temperature under open air. The reaction proceeded efficiently affording the desired 1,2-dithioles in good yields having various functional groups of a diverse electronic and steric nature. This approach avoids possible toxicity and tiresome workup conditions and features easy to handle, cheap, and readily accessible reagents, O2 as a green oxidant, and gram-scale ability. Notably, the final S-S bond formation and cascade ring construction follow a radical pathway, which has been recognized via a radical trapping experiment with BHT during the course of the reaction. Notably, the exocyclic C═N bond at position 3 of 1,2-dithiole possesses Z stereochemistry.

7.
Org Lett ; 25(4): 642-646, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36656125

RESUMO

We describe herein a chemo- and regioselective cascade annulation between ß-ketothioamides and diazo-substituted hypervalent iodine reagents under transition-metal-free and base-free conditions at room temperature. Thus, a divergent construction of fused-heterocyclic scaffold thiazolothiadiazoles has been achieved with the advantages of operational simplicity, scalability, broad substrate compatibility, and mild reaction conditions. This one-pot strategy not only avoids potential toxicity but also broadens the arsenal of synthetic methods to obtain fused N,S-heterocyclic frameworks.

8.
J Org Chem ; 87(21): 13935-13944, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36205379

RESUMO

An operationally simple, practical, and efficient cascade approach employing α-allyl dithioesters and NBS/NIS has been achieved to access a series of dihydrothiophenes and thiophenes containing diverse functional groups of different electronic and steric natures in good to excellent yields at room temperature in open air. The reaction proceeds via the electrophilic addition of a halogen source (NBS/NIS) to an allylic double bond, followed by intramolecular regio- and chemoselective S-cyclization. This protocol avoids potential toxicity and tedious work-up conditions, and features easy synthesis from readily available starting materials under catalyst-free conditions. Furthermore, 4,5-dihydrothiophenes were aromatized to thiophenes by treatment with KOH in DMF at room temperature. A probable mechanism for the formation of dihydrothiophenes and thiophenes from α-allyl dithioesters has been suggested. Notably, a large-scale experiment and the transformations of products indicated the potential utility of this reaction compared to competing processes for the synthesis of 4,5-dihydrothiophenes and thiophenes.

9.
Org Lett ; 24(32): 6078-6082, 2022 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-35925810

RESUMO

Base promoted one-pot annulative coupling of 1,2,3,4-tetrahydroisoquinolines (THIQs) with hypervalent iodine(III) species aryliodonio diazo compounds has been devised for the direct construction of 1,2,4-triazolo[3,4-a]isoquinoline derivatives at room temperature in open air for the first time. This approach involves [2 + 3] cascade annulation of nucleophilic THIQ with an electrophilic aryliodonio diazo compound via N-H and α-C1(sp3)-H difunctionalization of THIQ.


Assuntos
Iodo , Tetra-Hidroisoquinolinas , Compostos Azo , Iodetos , Isoquinolinas
10.
Org Biomol Chem ; 20(34): 6784-6798, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35959842

RESUMO

Magnesium catalysis proved to be efficient towards [3 + 3] chemo- and diastereoselective heteroannulation employing racemic Morita-Baylis-Hillman (MBH) acetate as the C3 unit and α-enolic dithioester as the C2S1 unit, leading to highly substituted 3,4-dihydro-2H-thiopyrans in excellent yields. The compatibility with a wide range of functional groups makes this domino formation of C-C and C-S bonds interesting. DFT analyses for the regioselective formation of the intermediate was performed.

11.
J Org Chem ; 87(18): 12342-12351, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36037527

RESUMO

A concise and practical one-pot sustainable approach for expedient synthesis of 2-arylimino-2H-chromenes by two-component cascade [4 + 2] annulative coupling of easily available 2-hydroxybenzaldehydes with ß-ketothioamides has been developed in good yields for the first time. Remarkably, metal- and additive-free conditions, use of simple K2CO3 as a mild base, open atmosphere, exclusive regioselectivity, step/atom economy, nonhazardous reagents, and easy purification are added characteristics to the strategy. This annulative protocol will not only provide an efficient method to access diverse chromene scaffolds, but also enrich the research domain of ß-ketothioamides.

12.
J Org Chem ; 87(13): 8656-8671, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35731944

RESUMO

Brønsted acid- and/or Lewis acid-catalyzed selective C3-allylation and formal [3 + 2]-annulation of spiro-aziridine oxindoles with allylsilanes have been demonstrated to deliver direct access to 3-allyl-3-aminomethyl oxindoles and 5-silyl methyl spiro[pyrrolidine-3,3'-oxindoles], respectively. The acid-catalyzed methods do not provide any stereoselectivity when chiral spiroaziridines are used. However, the reaction of nonracemic sprioaziridines with allyl-Grignard reagent under catalyst-free conditions afforded 3-allyl-3-aminomethyl oxindoles with good stereoselectivity (ee up to 80%). The allylation protocol is utilized for the short synthesis of coerulescine and various 5'-substituted spiro[pyrrolidine-3,3'-oxindoles].


Assuntos
Aziridinas , Compostos de Espiro , Compostos de Anilina , Indóis , Estrutura Molecular , Oxindóis , Pirrolidinas
13.
Org Lett ; 24(15): 2815-2820, 2022 04 22.
Artigo em Inglês | MEDLINE | ID: mdl-35412324

RESUMO

Herein, we described an efficient method for the construction of highly functionalized diazirines from the carbohydrazide and diazo-substituted hypervalent iodine reagents. Unambiguous transformation has been designed with user applicable and easy practicable conditions. Remarkably, d-glucose, menthol, aspirin, proline, and lithocholic acid were efficiently diazirinated. Furthermore, the method is mild, robust, and highly selective, which successfully converted a variety of aryl, alkyl, benzyl, and heterocyclic hydrazides into the corresponding diazirine derivatives.


Assuntos
Iodo , Diazometano , Indicadores e Reagentes , Iodetos
14.
Am J Infect Control ; 50(7): 792-798, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34742749

RESUMO

BACKGROUND: Healthcare-associated infections (HAIs) are a persistent clinical challenge caused primarily by bacteria on the skin. Proper utilization of optimized antiseptic skin preparation solutions helps reduce the prevalence and impact of HAIs by decreasing patient skin microorganisms preoperatively. The purpose of this study was to evaluate the efficacy of 2 antimicrobial solutions containing iodine and isopropyl alcohol (IPA): Povidone iodine (PVP-I) with IPA (ie, PVP-I+IPA, PurPrep) and Iodine Povacrylex+IPA (DuraPrep). METHODS: The antimicrobial activity of the test solutions was evaluated in vitro by determinations of minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) against 1105 diverse microbial isolates and a time-kill assay to evaluate efficacy against 120 strains of Gram-positive and Gram-negative bacteria and yeasts. Peel tests were performed between skin samples treated with test solutions and representative drape/dressing materials to determine effects of test solutions on the biomechanical adhesion properties. Finally, an Institutional Review Board (IRB)-approved, randomized, controlled, single-center, partially blinded in vivo study was performed to assess the immediate and persistent antimicrobial activity of the test solutions on the abdomen and groin. RESULTS: Both PVP-I+IPA and Iodine Povacrylex+IPA solutions demonstrated broad-spectrum antimicrobial activity with MIC and MBC at less than 1% of the full-strength concentration of each product against a wide variety of microorganisms. In the time-kill tests, both solutions were able to successfully reduce all microbial populations by 99.99% (ie, 4 log10) at the contact times of 30 seconds, 2 minutes and 10 minutes. The 2 solutions showed relatively similar adhesion results when tested with 3 representative operating room materials. Both PVP-I+IPA and Iodine Povacrylex+IPA met the expected Food and Drug Administration (FDA) efficacy requirements at 10 minutes and 6 hours post-treatment for both anatomic sites (ie, groin, and abdomen) in the clinical study, with no safety issues or adverse events. CONCLUSIONS: Analysis of the in vitro antimicrobial activity, biomechanical adhesive strength, and in vivo efficacy of PVP-I+IPA demonstrated similar results compared to Iodine Povacrylex+IPA. Both products were efficacious at reducing or eliminating a wide range of clinically-relevant microorganisms in lab-based and clinical settings, supporting their use as antiseptic skin preparation solutions to reduce bacteria on the skin that can cause infection.


Assuntos
Anti-Infecciosos Locais , Iodo , 2-Propanol/farmacologia , Antibacterianos/uso terapêutico , Anti-Infecciosos Locais/farmacologia , Anti-Infecciosos Locais/uso terapêutico , Bactérias , Clorexidina/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Humanos , Iodo/farmacologia , Povidona-Iodo/farmacologia , Pele/microbiologia , Infecção da Ferida Cirúrgica/epidemiologia
15.
J Org Chem ; 86(24): 18004-18016, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34818010

RESUMO

We have developed an electrochemical approach for the synthesis of fully substituted 1,2,3-thiadiazoles from α-phenylhydrazones at room temperature, which is very challenging and complementary to the conventional thermal reactions. The key step involves anodic oxidation of phenylhydrazone derivatives at a constant current followed by N,S-heterocyclization. The protocol is remarkable in that it is free of a base and free of an external oxidant and can be converted to a gram scale for postsynthetic drug development with functional thiadiazoles. Most importantly, the electrochemical transformation reflected efficient electro-oxidation with an operationally friendly easy procedure with ample functional molecules. Cyclic voltammograms support the mechanism of this electro-oxidative cyclization process.


Assuntos
Tiadiazóis , Ciclização , Hidrazonas , Oxirredução
16.
Org Lett ; 23(10): 3809-3813, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33956460

RESUMO

An operationally simple and sustainable one-pot photo-oxidative formal [3 + 2] heterocyclization of ß-ketothioamides with aryldiazonium salts catalyzed by Ru(bpy)3Cl2 has been realized to provide 2,4-disubstituted 5-imino-1,2,3-thiadiazoles in good to high yields under mild reaction conditions for the first time. The reaction proceeded via an α-phenylhydrazone adduct of thioamides leading to 1,2,3-thiadiazoles via N-S bond formation at room temperature. Notably, the products possess Z-stereochemistry with regard to the exocyclic C═N double bond at the 5-position of the ring.

17.
J Org Chem ; 86(8): 5908-5921, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33821649

RESUMO

The unique properties of ketoximes are used prominently for the synthesis of heterocycles. In contrast, their potential to absorb light and photoelectron transfer processes remains challenging. Widespread interest in controlling direct excitation of ketoxime tacticity unlocks unconventional reaction pathways, enabling photochemical intramolecular skeletal modification to constitute alkynyl sulfides that cannot be realized via traditional activation. Despite decades of advancements, the alkynyl sulfides, particularly those composed of polar functionalities and derived from renewable sources, remain unknown. These findings demonstrate the importance of decelerated ketoxime from ß-oxodithioester for the identification of reaction conditions. The method uses mild reaction conditions to generate excited-state photoreductant for the functionalization of an array of alkynyl sulfides. Additionally, a fundamental understanding of elementary steps using electrochemical and spectroscopic techniques/experiments revealed a PCET pathway to this transformation, while the involved substrates and their properties with improved economical tools indicated the translational potential of this method.


Assuntos
Oximas , Sulfetos , Catálise
18.
Environ Int ; 146: 106260, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33221593

RESUMO

Bisphenol A (BPA) is an industrial plasticizer widely found in consumer products, and exposure to BPA during early development has been associated with the prevalence of various cardiometabolic diseases including obesity, metabolic syndrome, type 2 diabetes, and cardiovascular diseases. To elucidate the molecular perturbations underlying the connection of low-dose prenatal BPA exposure to cardiometabolic diseases, we conducted a multi-dimensional systems biology study assessing the liver transcriptome, gut microbial community, and diverse metabolic phenotypes in both male and female mouse offspring exposed to 5 µg/kg/day BPA during gestation. Prenatal exposure to low-dose BPA not only significantly affected liver genes involved in oxidative phosphorylation, PPAR signaling and fatty acid metabolism, but also affected the gut microbial composition in an age- and sex-dependent manner. Bacteria such as those belonging to the S24-7 and Lachnospiraceae families were correlated with offspring phenotypes, differentially expressed liver metabolic genes such as Acadl and Dgat1, and key drivers identified in our gene network modeling such as Malat1 and Apoa2. This multiomics study provides insight into the relationship between gut bacteria and host liver genes that could contribute to cardiometabolic disease risks upon low-dose BPA exposure.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Efeitos Tardios da Exposição Pré-Natal , Animais , Compostos Benzidrílicos/metabolismo , Compostos Benzidrílicos/toxicidade , Feminino , Fígado/metabolismo , Masculino , Redes e Vias Metabólicas , Camundongos , Fenóis , Gravidez , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Toxicogenética
19.
J Org Chem ; 85(15): 10098-10109, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32648747

RESUMO

A metal- and oxidant-free photoinduced strategy for thioxo sulfur-selective trifluoromethylation of ß-ketodithioesters at room temperature is reported. Excellent Z/E-stereoselectivity has been achieved with cheap and viable Langlois' reagent (CF3SO2Na, sodium triflinate) in the presence of eosin Y, which acts as a hydrogen atom transfer (HAT) catalyst. The reaction proceeds via disulfide intermediate disulfanediylbis(3-(alkylthio)-1-phenylprop-2-en-1-one) (a dimer of ß-ketodithioester) followed by complementing proton-coupled electron transfer-mediated reverse HAT cycle of eosin Y. This operationally simple and efficient protocol allows direct access to triflinated α-oxoketene dithioacetals in good to excellent yields bearing diverse synthetically useful functional groups of different electronic and steric nature.

20.
J Org Chem ; 85(13): 8320-8329, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32500711

RESUMO

An operationally simple and efficient one-pot protocol for the synthesis of highly functionalized thiazolidin-4-ones and thiazolines has been devised via Rh(OAc)2-catalyzed annulative coupling of ß-ketothioamides with diazo compounds under mild reaction conditions for the first time. This double functionalization of diazo compounds proceeds via selective S-alkylation followed by intramolecular N-cyclization enabling the formation of C-S and C-N bonds at moderate temperature. Notably, the products possess Z-stereochemistry with regard to the exocyclic C═C double bond at the 2-position of the ring. Further, the synthetic utility of the strategy has been revealed to access 2,3-dihydrobenzo[d]thiazoles. Remarkably, atom economy and tolerance of a wide range of functional groups are added characteristics to this strategy.

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