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1.
J Org Chem ; 89(7): 4826-4839, 2024 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-38471124

RESUMO

Heavy-atom-free photosensitizers are potentially suitable for use in photodynamic therapy (PDT). In this contribution, a new family of unsymmetrical benzothieno-fused BODIPYs with reactive oxygen efficiency up to 50% in air-saturated toluene was reported. Their efficient intersystem crossing (ISC) resulted in the generation of both 1O2 and O2-• under irradiation. More importantly, the PDT efficacy of a respective 4-methoxystyryl-modified benzothieno-fused BODIPY in living cells exhibited an extremely high phototoxicity with an ultralow IC50 value of 2.78 nM. The results revealed that the incorporation of an electron-donating group at the α-position of the unsymmetrical benzothieno-fused BODIPY platform might be an effective approach for developing long-wavelength absorbing heavy-atom-free photosensitizers for precision cancer therapy.


Assuntos
Compostos de Boro , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Elétrons , Oxigênio , Tolueno
2.
J Org Chem ; 88(20): 14368-14376, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37792439

RESUMO

A novel family of bisbenzothieno[b]-fused BODIPYs containing seven fused aromatic rings has been developed from readily available benzothieo[3,2-b]pyrroles through an efficient two-step synthetic route, exhibiting planar skeletons with excellent photostabilities, deep-red absorptions, and near-infrared emissions (up to 753 nm). Importantly, the thin-film transistors based on BTB with a meso-dimethylamino-phenyl group exhibit unipolar n-type charge transporting characteristics with a high electron mobility of 0.013 cm2 V-1 s-1.

3.
J Org Chem ; 87(15): 9769-9781, 2022 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-35866754

RESUMO

Different Lewis acid promotor-steered highly regioselective phosphorylation of tertiary enamides with diverse H-phosphonates or H-phosphine oxides was developed. Under the catalysis of iron salt, the phosphonyl group was introduced into the α-position of tertiary enamides, affording various α-phosphorylated amides in high efficiency. On the other hand, the ß-phosphorylated tertiary enamides were efficiently obtained as the products in the presence of manganese(III) acetylacetonate.


Assuntos
Amidas , Ácidos de Lewis , Catálise , Estrutura Molecular , Fosforilação
4.
J Org Chem ; 87(5): 3014-3024, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35073080

RESUMO

An efficient Au(I)-catalyzed intramolecular cascade reaction of tertiary enamides tethered an alkynyl group has been developed. The process is composed of a propargyl-claisen rearrangement and 5-exo-dig cyclization. This protocol provided a powerful method for the preparation of a variety of pentasubstituted pyrroles derivatives with excellent functional group tolerance in excellent yields. Scale-up experiment and chemical transformations of products exhibited the versatility of tertiary enamides in organic synthesis again.


Assuntos
Ouro , Pirróis , Catálise , Ciclização , Ouro/química , Estrutura Molecular , Pirróis/química
5.
Inorg Chem ; 61(42): 16718-16729, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36206458

RESUMO

Tetracoordinated organoboron dyes exhibiting strong fluorescence in either solution or the solid state are currently receiving much attraction in view of their photovoltaic, optoelectronic, and biological applications. Herein, a series of aromatic-ring-fused BOPPY dyes have been developed by one-pot condensation of formylated isoindoles or indoles and pyridinylhydrazine followed by subsequent borylation coordination. The facile synthesis provides excellent diversity of these unsymmetrical α-benzo- and ß-benzothiophene-fused BOPPY dyes with intriguing photophysical properties owing to their rigid and planar structure and extended π-conjugation while containing a reactive site. They display intense green to orange fluorescence in solution and red-to-near-infrared emission in the solid state, with high fluorescence quantum yields up to 92 and 21%, respectively, relatively large Stokes shifts, and excellent photostability. Furthermore, two representative benzo-fused BOPPY probes with morpholine or benzenesulfonamide groups were developed and used to selectively "light up" the subcellular organelles such as lysosomes and endoplasmic reticulum under ultralow concentration, respectively.


Assuntos
Corantes Fluorescentes , Indóis , Corantes Fluorescentes/química , Ionóforos , Oxirredução , Morfolinas , Isoindóis
6.
Org Biomol Chem ; 19(37): 8086-8095, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34476428

RESUMO

An exquisite metal-free cascade cyclization reaction of 2-acylbenzoic acids with amines was developed, which provided a powerful method for the one-pot synthesis of diverse isoindoloisoquinoline and benzoindolizinoindole derivatives. This protocol avoided the use of metal catalysts, proceeded with high efficiency and had broad substrate scope. These resulting products could be transformed into tertiary amines under the reduction of LiAlH4/AlCl3, followed by the Hofmann elimination offering lots of nitrogen-containing nine-membered ring compounds in excellent yields. All synthesized products containing fused N-polycyclic skeletons were difficult to be constructed using traditional methods and they have a wide range of applications in the pharmaceutical area.


Assuntos
Aminas
7.
Org Biomol Chem ; 18(48): 9762-9774, 2020 12 28.
Artigo em Inglês | MEDLINE | ID: mdl-33237116

RESUMO

In recent years, considerable attention has been devoted to the exploration of novel synthetic methods for fluoro-lactams due to their significant biological and pharmaceutical activities. This review summarizes recently established strategies for synthesizing fluorine-substituted lactams, including fluoro-ß-lactams, fluoro-γ-lactams, and fluoro-δ-lactams. Additionally, the reaction scopes, limitations, and mechanisms are discussed.


Assuntos
beta-Lactamas
8.
Zhongguo Zhong Yao Za Zhi ; 45(10): 2221-2231, 2020 May.
Artigo em Chinês | MEDLINE | ID: mdl-32495574

RESUMO

In this paper, we analyzed medical records of 40 patients with coronavirus disease 2019(COVID-19), in order to explore the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The investigation was based on the results of a previous animal test, which was aimed to investigate and confirme the clinical efficacy of Matrine and Sodium Chloride Injection in the treatment of COVID-19. The animal test demonstrated that Matrine and Sodium Chloride Injection has a significant therapeutic effect on the human coronavirus pneumonia for the model mice. The lung inhibition index reached up to 86.86%. The evaluation was conducted on 40 confirmed cases of COVID-19 treated at Jingzhou Hospital of Infectious Disease(Chest Hospital) of Hubei Pro-vince from January 30~(th) to March 21~(th), 2020. In these cases, patients were treated with other integrated Chinese and Western medicines regimens in the recommended Matrine and Sodium Chloride Injection diagnosis and treatment regimen. The clinical manifestations, laboratory data, nucleic acid clearance time, and imaging data were compared and analyzed before and after treatment. After administration with Matrine and Sodium Chloride Injection, the clinical symptoms of 40 cases were alleviated markedly, and their blood analysis and biochemical indexes returned to normal. The lung CT showed more than 50% of lesion absorption rate, and the viral nucleic acid test showed the average clearance time of patients was 16.6 days, and the average length of hospital stay was 25.9 days. After administration with Matrine and Sodium Chloride Injection, the symptoms of cough and fatigue were alleviated significantly, and the appetite was significantly improved compared with before, especially for patients with gastrointestinal symptoms. Additionally, laboratory indicators, especially absolute value and ratio of lymphocytes and CRP were significantly alleviated. According to the chest CT for short-term review, the absorption of lung lesions was faster than before, especially for grid-like and fibrotic lesions. Compared with antiviral drugs, such as Abidol and Kriging, the nucleic acid clearance time was significantly shorter than the cases treated with Matrine and Sodium Chloride Injection. The clinical effective rate of 40 cases was 100.0%. We believed that Matrine and Sodium Chloride Injection have a good clinical effect in the treatment of COVID-19, and suggested increasing the clinical application and further conducting large-sample-size cli-nical verification.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Alcaloides , Animais , COVID-19 , Modelos Animais de Doenças , Camundongos , Quinolizinas , SARS-CoV-2 , Cloreto de Sódio , Resultado do Tratamento , Matrinas
9.
Org Biomol Chem ; 13(7): 1992-5, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25567104

RESUMO

Treatment of methyl mesopyropheophorbide a with formaldehyde under basic conditions gave a novel 13(2)-methylene derivative in 85% yield; under acidic conditions, the corresponding 20-hydroxymethyl derivative was obtained in 65% yield. The high reactivity of the enone structural motif existed in the former product provides a unique way to construct some novel chlorophyll a derivatives for various applications. Stereoselective Michael reaction of this compound is studied and discussed.


Assuntos
Formaldeído/química , Porfirinas/síntese química , Conformação Molecular , Porfirinas/química , Estereoisomerismo
10.
Bioorg Med Chem ; 23(8): 1684-90, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25797162

RESUMO

A series of chlorophyll a-based chlorins conjugated with pyridyl or quinoxalyl group at different positions were synthesized, characterized and evaluated for their photodynamic effect in vitro. It was found that all the pyridyl and quinoxalyl chlorins showed promising photocytotoxicities but nontoxic without irradiation in HeLa cells, and the substituted types and positions had a significant influence on the photocytotoxicities of the chlorophyll a-based chlorins. All the chlorins with a pyridyl group at the C-D ring end exhibited relatively high photocytotoxicity as compared to those with 3(2)-pyridyl. Among them, compound 12 conjugated with a pyridyl group at its C12 position showed the best photodynamic effect in HeLa cells with an IC50 value of 0.033µM. These facts, associated with the relative high long wavelength absorptions of those chlorins may provide valuable ways to design and prepare promising photosensitizers for application in photodynamic therapy.


Assuntos
Clorofila/química , Clorofila/farmacologia , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química , Porfirinas/farmacologia , Clorofila/síntese química , Clorofila A , Células HeLa , Humanos , Fotoquimioterapia , Fármacos Fotossensibilizantes/síntese química , Porfirinas/síntese química , Piridinas/síntese química , Piridinas/química , Piridinas/farmacologia , Quinoxalinas/síntese química , Quinoxalinas/química , Quinoxalinas/farmacologia
11.
Chem Commun (Camb) ; 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-39163003

RESUMO

The twist fusion of a benzothiophene group and the introduction of a 4-methyloxystyryl donor group to the BODIPY core resulted in large spin-orbit coupling values and smaller singlet-triplet energy gaps for the novel infrared absorbed photosensitizers named BSBDP. They show a high reactive oxygen species efficiency exceeding 69% and a fluorescence quantum yield of 23% and are successfully applied in imaging-guided photodynamic therapy in vitro and in vivo.

12.
Chem Commun (Camb) ; 60(31): 4206-4209, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38523529

RESUMO

A novel silyl radical-induced cascade silylation/cyclization of 1,7-dienes has been realized employing readily available hydrosilanes as a silicon source and Cu(I) salt as a catalyst. This protocol introduces diverse silicon fragments into a challenging 7-membered ring structure and provides an efficient approach to a wide array of biologically important silyl-substituted benzo[b]azepin-2-ones. Several control experiments suggest that the reaction undergoes a free radical process. The gram-scale synthesis and late-stage transformations further demonstrate the scalability and applicability of the reaction in organic synthesis.

13.
Microsyst Nanoeng ; 10: 111, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39157211

RESUMO

Pipe contaminant detection holds considerable importance within various industries, such as the aviation, maritime, medicine, and other pertinent fields. This capability is beneficial for forecasting equipment potential failures, ascertaining operational situations, timely maintenance, and lifespan prediction. However, the majority of existing methods operate offline, and the detectable parameters online are relatively singular. This constraint hampers real-time on-site detection and comprehensive assessments of equipment status. To address these challenges, this paper proposes a sensing method that integrates an ultrasonic unit and an electromagnetic inductive unit for the real-time detection of diverse contaminants and flow rates within a pipeline. The ultrasonic unit comprises a flexible transducer patch fabricated through micromachining technology, which can not only make installation easier but also focus the sound field. Moreover, the sensing unit incorporates three symmetrical solenoid coils. Through a comprehensive analysis of ultrasonic and induction signals, the proposed method can be used to effectively discriminate magnetic metal particles (e.g., iron), nonmagnetic metal particles (e.g., copper), nonmetallic particles (e.g., ceramics), and bubbles. This inclusive categorization encompasses nearly all types of contaminants that may be present in a pipeline. Furthermore, the fluid velocity can be determined through the ultrasonic Doppler frequency shift. The efficacy of the proposed detection principle has been validated by mathematical models and finite element simulations. Various contaminants with diverse velocities were systematically tested within a 14 mm diameter pipe. The experimental results demonstrate that the proposed sensor can effectively detect contaminants within the 0.5-3 mm range, accurately distinguish contaminant types, and measure flow velocity.

14.
Sci Total Environ ; 885: 163843, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37137362

RESUMO

Nitrogen (N) and phosphorus (P) are two crucial limiting mineral elements for terrestrial plants. Although the leaf N:P ratio is extensively used to indicate plant nutrient limitations, the critical N:P ratios cannot be universally applied. Some investigations have suggested that leaf nitrogen isotopes (δ15N) can provide another proxy for nutrient limitations along with the N:P ratio, but the negative relationships between N:P and δ15N were mainly limited to fertilization experiments. It will obviously benefit the study of the nature of nutrient limitations if the relationship could be explained more generally. We analyzed leaf δ15N, N, and P contents across a northeast-southwest transect in China. Leaf δ15N was weakly negatively correlated with leaf N:P ratios for all plants, while there was no correlation between them for various plant groups, including different growth forms, genera, and species across the entire N:P range. This suggests that the use of leaf δ15N in indicating the shift of nutrient limitations across the whole N:P range still requires more validated field investigations. Notably, negative relationships between δ15N and N:P hold for plants with N:P ratios between 10 and 20 but not for plants with N:P ratios lower than 10 or higher than 20. That is, changes in leaf δ15N along with the N:P ratio of plants that are co-limited by N and P can exhibit variations in plant nutrient limitations, whereas plants that are strictly limited by N and P cannot. Moreover, these relationships are not altered by vegetation type, soil type, MAP, or MAT, indicating that the use of leaf δ15N in reflecting shifts in nutrient limitations, depending on the plant nutrient limitation range, is general. We examined the relationships between leaf δ15N and the N:P ratio across an extensive transect, providing references for the widespread use of leaf δ15N in reflecting shifts in nutrient limitation.


Assuntos
Nitrogênio , Fósforo , Folhas de Planta , Plantas , China , Ecossistema , Nitrogênio/análise , Isótopos de Nitrogênio , Fósforo/análise , Folhas de Planta/química , Solo
15.
ACS Omega ; 8(24): 21941-21947, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37360422

RESUMO

In this study, we condensed methyl pyropheophorbide-a (2) with 1,2-phenylenediamine to synthesize benzimidazolo-chlorin (3a) as an effective near-infrared photosensitizer (PS) with an absorption maximum of 730 nm. The ability of 3a to generate singlet oxygen, as well as its photodynamic effect on A549 and HeLa cells, was investigated. PS exhibited strong phototoxicity and negligible dark toxicity. Its structure was examined by UV-visible spectroscopy, nuclear magnetic resonance, and high-resolution fast atom bombardment mass spectrometry.

16.
Chem Commun (Camb) ; 59(94): 13986-13989, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37937533

RESUMO

New and dynamical chiral co-assembled systems bearing BOPPY were successfully developed with amplified CPL signals. Remarkably, these stable chiral co-assemblies prepared at high concentrations retain uniform microrods and exceptional chiroptical performance (glum = 0.028, ΦF = 14%) after 48 h.

17.
Plants (Basel) ; 12(1)2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36616216

RESUMO

Seed release is crucial in the reproductive cycle of many desert plant species, but their responses to precipitation changes are still unclear. To clarify the response patterns, we conducted a long-term in situ water addition experiment with five treatments, including natural precipitation (control) plus an extra 25%, 50%, 75%, and 100% of the local mean annual precipitation (145 mm), in a temperate desert in northwestern China. Both the onset and end of the seed release phenophase of the locally dominant shrub, Nitraria tangutorum, were observed from 2012 to 2018. The results showed that both the onset and end time of seed release, especially the end time, were significantly affected by water addition treatment. On average, the end time of seed release was advanced by 3.9 d, 7.3 d, 10.8 d, and 3.8 d under +25%, +50%, +75%, and +100% water addition treatments, respectively, over the seven-year study, compared with the control. The changes in the onset time were relatively small (only several hours), and the duration of seed release was shortened by 4.0 d, 7.5 d, 10.8 d, and 2.0 d under +25%, +50%, +75%, and +100% water addition treatments, respectively. The onset and end time of seed release varied greatly between the years. Preceding fruit ripening and summer temperature jointly regulated the inter-annual variation of the onset time of seed release, while the cumulative summer precipitation played a key role in driving the inter-annual variation of the end time. The annual mean temperature controlled the inter-annual variation of the seed release duration, and these interactions were all non-linear.

18.
Plants (Basel) ; 11(12)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35736729

RESUMO

Fruit setting and ripening are crucial in the reproductive cycle of many desert plant species, but their response to precipitation changes is still unclear. To clarify the response patterns, a long-term in situ water addition experiment with five treatments, namely natural precipitation (control) plus an extra 25%, 50%, 75%, and 100% of the local mean annual precipitation (145 mm), was conducted in a temperate desert in northwestern China. A whole series of fruiting events including the onset, peak, and end of fruit setting and the onset, peak, and end of fruit ripening of a locally dominant shrub, Nitraria tangutorum, were observed from 2012 to 2018. The results show that (1) water addition treatments had no significant effects on all six fruiting events in almost all years, and the occurrence time of almost all fruiting events remained relatively stable compared with leaf phenology and flowering phenology after the water addition treatments; (2) the occurrence times of all fruiting events were not correlated to the amounts of water added in the treatments; (3) there are significant inter-annual variations in each fruiting event. However, neither temperature nor precipitation play key roles, but the preceding flowering events drive their inter-annual variation.

19.
Org Lett ; 24(12): 2288-2293, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35319211

RESUMO

A novel and simple organoselenium-involved 7-membered cyclization to access diverse seleno-benzo[b]azepines has been developed. This protocol involves an electrophilic cyclization process and is accomplished under mild conditions. Discussion of the mechanism rationalizes the regioselectivity observed in transformation. The studies of further transformation of seleno-benzo[b]azepines and large-scale experiment reveal the promising utility of this methodology.

20.
Biomed Pharmacother ; 142: 111995, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34435595

RESUMO

The clinical application of cisplatin was mainly limited by severe nephrotoxicity. Danshensu was the main pharmacological active diterpenoids which extracted from the roots of Salvia milthiorriza Bunge. This study is aimed to investigate the protective effects and potential mechanisms of Danshensu against cisplatin-induced nephrotoxicity. After fasting for 12 h, all mice groups except the control group were administered a single intraperitoneal injection of 25 mg/kg cisplatin. 1 h later, cisplatin (25 mg/kg) + Danshensu (15 mg/kg, 30 mg/kg, 60 mg/kg) groups were treated with corresponding doses of Danshensu once a day for 7 consecutive days. Blood urea nitrogen (BUN), creatinine, reactive oxygen species (ROS), superoxide dismutase (SOD), Glutathione peroxidase (GPx), Catalase (CAT) and malondialdehyde (MDA) were assayed in this study. The expression of inflammatory cytokines TNF-α, IL-6 and IL-1ß were examined by ELISA. The results showed that Danshensu could improve kidney damage, attenuate serum BUN, creatinine, cytokines and oxidative stress markers. Further studies showed that Danshensu can induce Nrf2/HO-1 activation and inhibition of NF-κB pathway. In conclusion, Danshensu exerts the protective effects on cisplatin-induced nephrotoxicity, which may be related to the activation of Nrf2/HO-1 and inhibition of NF-ĸB pathway.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Nefropatias/prevenção & controle , Lactatos/farmacologia , Animais , Nitrogênio da Ureia Sanguínea , Relação Dose-Resposta a Droga , Heme Oxigenase-1/metabolismo , Nefropatias/induzido quimicamente , Lactatos/administração & dosagem , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
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