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1.
Int J Mol Sci ; 23(19)2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-36232422

RESUMO

Microwave-assisted reaction between 2-(3-oxoindolin-2-yl)-2-phenylacetonitriles andbenzene-1,2-diamines leads to the high-yielding formation of the corresponding quinoxalines as sole, easily isolaable products. The featured transformation involves unusual extrusion of phenylacetonitrile molecule and could be performed in a short sequence starting from commonly available indoles and nitroolefins.


Assuntos
Diaminas , Quinoxalinas , Acetonitrilas , Benzeno , Indóis , Estrutura Molecular
2.
J Org Chem ; 87(21): 13955-13964, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36260110

RESUMO

Unusual cascade transformation involving ring opening and 1,2-alkyl shift was observed upon the reduction of 4'H-spiro[indole-3,5'-isoxazoles] or 2-(3-oxoindolin-2-yl)acetonitriles with sodium borohydride. This reaction allowed for expeditious and highly efficient preparation of 2-(1H-Indol-3-yl)acetamides with antiproliferative properties.


Assuntos
Acetamidas , Isoxazóis , Acetamidas/farmacologia , Relação Estrutura-Atividade , Indóis/farmacologia
3.
Molecules ; 27(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35335265

RESUMO

3-(1H-Indol-3-yl)benzofuran-2(3H)-ones were efficiently accessed via polyphosphoric acid-mediated condensation of 3-(2-nitrovinyl)-1H-indoles with phenols.


Assuntos
Benzofuranos , Indóis , Fenóis
4.
Molecules ; 26(18)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34577163

RESUMO

Nitroalkanes activated with polyphosphoric acid could serve as efficient electrophiles in reactions with amines and hydrazines, enabling various cascade transformations toward heterocyclic systems. This strategy was developed for an innovative synthetic protocol employing simultaneous or sequential annulation of two different heterocyclic cores, affording [1,2,4]triazolo[4,3-a]quinolines with 1,3,4-oxadiazole substituents.

5.
Org Biomol Chem ; 19(33): 7234-7245, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34387294

RESUMO

Indolizines and pyrazolo[1,5-a]pyridines were prepared via [3 + 2]-cycloaddition of pyridinium ylides to 1-chloro-2-nitrostyrenes. The synthesized molecules were evaluated for antiproliferative activities against a BE(2)-C neuroblastoma cell line with several compounds decreasing the viability of cancer cells. Indolizine 9db showed higher potency than that of all-trans-retinoic acid, an approved cancer drug. Mechanistically, it was found to inhibit tubulin polymerization and it is thus proposed that the discovered chemistry can be exploited for the development of novel microtubule-targeting anticancer agents.


Assuntos
Moduladores de Tubulina
6.
Molecules ; 26(14)2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34299549

RESUMO

Nitroalkanes activated with polyphosphoric acid serve as efficient electrophiles in reactions with various nucleophilic amines. Strategically placed second functionality allows for the design of annulation reactions enabling preparation of various heterocycles. This strategy was employed to develop an innovative synthetic approach towards 3,4-dihydroquinazolines from readily available 2-(aminomethyl)anilines.

7.
Indian J Radiol Imaging ; 31(1): 203-209, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34316128

RESUMO

Extraosseous Ewing's sarcoma (EES), first described in 1969, is a malignant mesenchymal tumor just like its intraosseous counterpart. Although Ewing's sarcomas are common bone tumors in young children, EESs are rarer and more commonly found in older children/adults, often carrying a poorer prognosis. We discuss the multimodality imaging features of EES and the differential diagnosis of an aggressive appearing mass in proximity to skeletal structures, with pathologic correlates. This review highlights the need to recognize the variability of radiologic findings in EES such as the presence of hemorrhage, rich vascularity, and cystic or necrotic regions and its imaging similarity to other neoplasms that are closely related pathologically.

8.
RSC Adv ; 11(57): 35937-35945, 2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35492804

RESUMO

The mechanistic rationale involving activation of nitroalkanes towards interaction with nucleophilic reagents in the presence of polyphosphoric acid (PPA) was re-evaluated. Could nitrile oxide moieties be formed during this process? This experiment demonstrates that at least in some cases this could happen, as generated nitrile oxides were successfully intercepted as adducts of [3 + 2] cycloadditions.

9.
Beilstein J Org Chem ; 16: 2903-2910, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299488

RESUMO

Imidazo[1,5-a]pyridines were efficiently prepared via the cyclization of 2-picolylamines with nitroalkanes electrophilically activated in the presence of phosphorous acid in polyphosphoric acid (PPA) medium.

10.
Org Biomol Chem ; 18(34): 6651-6664, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32813002

RESUMO

We discovered a reaction of nitroalkanes with 2-hydrazinylquinolines, 2-hydrazinylpyridines and bis-2,4-dihydrazinylpyrimidines in polyphosphoric acid (PPA) affording 1,2,4-triazolo[4,3-a]quinolines, 1,2,4-triazolo[4,3-a]pyridines and bis[1,2,4]triazolo[4,3-a:4',3'-c]pyrimidines, respectively. The reaction expands the scope of heterocyclic annulations involving phosphorylated nitronates, believed to be the electrophilic intermediates formed from nitroalkanes in PPA. Several of the synthesized triazoles showed promising anticancer activity by inducing differentiation in neuroblastoma cancer cells. Due to the urgent need for novel differentiation agents for neuroblastoma therapy, this finding warrants further evaluation of this class of compounds against neuroblastoma.

11.
Neurocrit Care ; 32(1): 302-305, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31468371

RESUMO

INTRODUCTION: The proportion of hospitals with specialist palliative care services in the USA has increased substantially over the past decade. Severe acute brain injury presents with unique challenges, especially regarding quality of life. The growth and increased recognition of neurocritical care as a subspecialty has not been paralleled by studies regarding how best to integrate palliative care for this unique patient population. Thus, we surveyed members of the Neurocritical Care Society (NCS) to explore current practice patterns, perceptions, and preferences regarding integration of palliative care in the neurological intensive care unit (Neuro-ICU). METHODS: We created a 19-item survey using SurveyMonkey to assess practice patterns, perceptions, and preferences of neurointensivists regarding integration of palliative care in the Neuro-ICU. The survey, approved by the NCS research committee, was distributed to all active members of the NCS. RESULTS: A total of 424 NCS members representing 19% of the 2200 list serve members completed the survey. The majority (58%) of respondents were attending physicians, who worked primarily in a dedicated Neuro-ICU (67%), at university affiliated academic medical centers (65%). Palliative care consultations are utilized infrequently (< 11%) by the majority of the respondents (59%). The most common indication for a palliative consultation was to discuss goals of care and make treatment decisions (73%). A large majority (77%) either agreed or strongly agreed that palliative care services were utilized in the management of difficult cases apart from discussions regarding withdrawal of life sustaining therapy. Palliative care needs of Neuro-ICU patients were considered different from patients in other ICUs by the majority of respondents (66%). CONCLUSION: Our study provides insights into the current perceptions, practice patterns, and preferences of neurointensivists as it relates to palliative care consultation in the Neuro-ICU.


Assuntos
Atitude do Pessoal de Saúde , Unidades de Terapia Intensiva , Neurologia , Neurocirurgia , Cuidados Paliativos , Padrões de Prática Médica , Encaminhamento e Consulta , Adulto , Tomada de Decisão Clínica , Feminino , Humanos , Masculino , Profissionais de Enfermagem , Planejamento de Assistência ao Paciente , Médicos , Inquéritos e Questionários
12.
J Pediatr Surg ; 55(1): 176-181, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31706607

RESUMO

BACKGROUND: Bronchoscopy is the standard of care for diagnosis and treatment of foreign body aspiration (FBA). Drawbacks of this approach include its invasiveness, the potential for exacerbation of reactive airway disease, and the need for general anesthesia. Computed tomography (CT) can potentially identify patients with FBA, thereby avoiding unnecessary bronchoscopies in patients with at-risk reactive airways. METHODS: A retrospective review was performed to identify patients who underwent CT and/or bronchoscopy for suspected foreign body aspiration (FBA) from June 2012 to September 2018. Variables included clinical history, exam findings, radiographic findings, and operative findings. A telephone survey was performed for patients who had a CT without bronchoscopy. Three radiologists performed rereads of all CTs. RESULTS: A total of 133 patients were evaluated for FBA, and 84 were treated with bronchoscopy. For those with a CT demonstrating a foreign body, findings were confirmed on bronchoscopy in 17/18 (94.4%). For those with bronchoscopy alone, 39/64 (60.9%) were found to have a foreign body (p < 0.01). CT excluded FBA in 49 patients. Sensitivity was 100%, specificity was 98%, and interobserver reliability was excellent (κ = 0.88). CONCLUSION: CT is an accurate and reliable diagnostic tool in the evaluation of FBA that can increase the rate of positive bronchoscopy. TYPE OF STUDY: Retrospective comparative study. LEVEL OF EVIDENCE: Level III.


Assuntos
Broncoscopia , Corpos Estranhos/diagnóstico por imagem , Corpos Estranhos/terapia , Sistema Respiratório/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Variações Dependentes do Observador , Estudos Retrospectivos , Sensibilidade e Especificidade , Procedimentos Desnecessários
14.
RSC Adv ; 9(12): 6636-6642, 2019 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35518500

RESUMO

A novel methodology for general and chemoselective preparation of non-symmetric 1,3,4-oxadiazoles is developed. This unusual reaction proceeds via polyphosphoric acid-assisted activation of nitroalkanes towards nucleophilic attack with acylhydrazides.

15.
Continuum (Minneap Minn) ; 24(6): 1789-1793, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30516606

RESUMO

Management of patients with terminal brain disorders can be medically, socially, and ethically complex. Although a growing number of feasible treatment options may exist, there are times when further treatment can no longer meaningfully improve either quality or length of life. Clinicians and patients should discuss goals of care while patients are capable of making their own decisions. However, because such discussions can be challenging, they are often postponed. These discussions are then conducted with patients' health care proxies after patients lose the capacity to make their own decisions. Disagreements may arise when a patient's surrogate desires continued aggressive interventions that are either biologically futile (incapable of producing the intended physiologic result) or potentially inappropriate (potentially capable of producing the patient's intended effect but in conflict with the medical team's ethical principles). This article explores best practices in addressing these types of conflicts in the critical care unit, but these concepts also broadly apply to other sites of care.


Assuntos
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Assistência Terminal/ética , Assistência Terminal/métodos , Humanos , Masculino , Pessoa de Meia-Idade
16.
J Org Chem ; 83(22): 13743-13753, 2018 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-30354138

RESUMO

A strain-release-driven, cation-templated nucleophilic 7- and 8- exo-trig-cyclization of tethered Boc-protected amines to cyclopropenes is described. The featured reaction proceeds in diastereo- and regioselective fashion and allows for preparation of the corresponding 2,5-diazabicyclo[5.1.0]octan-6-ones and 2,6-diazabicyclo[6.1.0]nonan-7-ones as sole products in high yields. Preliminary studies on anticancer activities of these novel cyclopropane-fused medium heterocycles were performed.

17.
Org Biomol Chem ; 16(23): 4325-4332, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29808901

RESUMO

The polyphosphoric acid-mediated reaction of 2-(2-aminophenyl)indenes with nitroalkenes was tested in the frame of synthetic studies towards CDK inhibitors with the paullone core. Unexpectedly, this reaction proceeded via a different mechanistic pathway affording derivatives of the natural alkaloid isocryptolepine. The scope of this unusual transformation was investigated and a mechanistic rationale explaining this outcome is offered.

18.
J Org Chem ; 83(10): 5650-5664, 2018 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-29696970

RESUMO

A strain-release-driven, cation-templated intramolecular nucleophilic addition of tethered alkoxides to prochiral cyclopropenes is described. Employment of chiral ß- and γ-amino alkoxides allowed for highly diastereoselective assembly of a small series of enantiopure cyclopropane-fused oxazepanones. It was shown that the chiral center at C-4 plays a crucial role in controlling desymmetrization of the cyclopropenyl moiety, instigated by a profound potassium-templated effect. The preliminary biological activities of the new cyclopropane-fused medium heterocycles against Gram-positive bacteria, Gram-negative bacteria, mycobacteria, cancer cells, and fungus were evaluated.


Assuntos
Amino Álcoois/farmacologia , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Ciclopropanos/farmacologia , Neoplasias/tratamento farmacológico , Amino Álcoois/química , Antibacterianos/síntese química , Antibacterianos/química , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Reação de Cicloadição , Ciclopropanos/síntese química , Ciclopropanos/química , Ensaios de Seleção de Medicamentos Antitumorais , Fungos/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Neoplasias/patologia , Potássio/química , Estereoisomerismo
19.
RSC Adv ; 8(64): 36980-36986, 2018 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-35558925

RESUMO

A second generation polyphosphoric acid-mediated one-pot three-component synthesis of indoloquinoline scaffold is developed. This improved version of the process involves electrophilically activated nitroalkanes for the installation of strategic C-C and C-N bonds and ring C assembly. This modification allows the elimination of unnecessary solvent change operations and all steps are carried out in a true, uninterrupted one-pot manner. A further improvement involves the possibility to install an ortho-amino group in situ. A synthetic application of this method is showcased by the concise synthesis of an isocryptolepine alkaloid and its synthetic analogs with potent anticancer activities.

20.
J Org Chem ; 82(6): 3011-3018, 2017 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-28253622

RESUMO

Indolo[3,2-c]quinolones have been efficiently synthesized via an acid-mediated, one-pot, three-component condensation of arylhydrazines, o-aminoacetophenones, and triazines or nitriles. The synthetic application of this method is showcased by the concise synthesis of isocryptolepine alkaloid and a series of its synthetic analogues with demonstrated cancer cell antiproliferative activities.


Assuntos
Alcaloides Indólicos/síntese química , Quinolinas/síntese química , Linhagem Celular Tumoral , Humanos , Alcaloides Indólicos/química , Quinolinas/química , Análise Espectral/métodos , Triazinas/química
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