ORGANIC & BIOMOLECULAR CHEMISTRY
·
2020
·Vol. 18
·期 18
·3575-3584
·
IF 3.412
Qifu Lin,Yongqi Yao,Wen Yang,Yun Tan,Shuqi Chen,Donghan Chen,Dingqiao Yang
A novel copper-catalyzed hydrothioetherification of oxa(aza)bicyclic alkenes with potassium thioacetate and aryl or alkyl iodides to synthesize unsymmetrical thioethers has been developed. Notably, the reaction with complete diastereoselectivity went through a syn-selective addition process to give exo-adducts. In addition, this protocol exhibited high efficiency and good functional group tolerance to afford the target thioethers in moderate to good yields. Based on the results of mechanistic investigations, a plausible mechanism was proposed.
研究领域:
有机化学
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合成化学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2019
·
IF 7.65
Jiapei Gu,Xiangqian Li,Guofu Zhou,Wanqiang Liu,Jinwei Gao,Qianming Wang
Formaldehyde (FA) is a chemical substance with tremendously noxious feature for human health and it causes serious damages to living organisms. The recognition of formaldehyde in the form of fluorescent signals has been extensively explored by using a few molecular scaffolds in buffer mediums. In particular, the study for sensing of formaldehyde both in solution and solid state has generated considerable interests. Herein, a new ratiometric fluorescent probe 1-(5-(9-phenyl-9H-carbazol-3-yl)thiophen-2-yl)but-3-en-1-amine ( SO-GJP ) has been synthesized for selective detection of FA based on aza-Cope reaction. In the presence of FA from 0 to 1.3 mM, the emission band of SO-GJP varies from 393 nm to 542 nm and the detection limit has been calculated to be 1.55 μM. The entrapment of SO-GJP onto the thin layer chromatography (TLC) plate leads to the successful detection of FA with sensitive color change from white to yellow. Moreover, the response mechanism has been explained by FA-induced 2-aza-Cope rearrangement within SO-GJP and the chemical processes are supported by density functional theory , fluorescence and UV–vis spectra. The integration of responsive units based on carbazole platform can serve as one of the powerful strategies by directly converting signals at different circumstances into fluorescence.
研究领域:
化学
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生物医学
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材料科学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY A
·
2017
·
IF 2.847
Zhongneng Zhou,Xueyao Zhou,Xueli Wang,Bin Jiang,Yongle Li,Jinquan Chen,Jianhua Xu
Excited state dynamics of 5-azacytosine (5-AC), 2,4-diamino-1,3,5-triazine (2,4-DT), and 2-amino-1,3,5-triazine (2-AT) were comprehensively investigated by steady state absorption, fluorescence, and femtosecond transient absorption measurements. Time-dependent density functional theory (TDDFT) calculations were performed to help assign the absorption bands and understand the excited state decay mechanisms. The experimental results of excited singlet state dynamics for 5-AC, 2,4-DT, and 2-AT with femtosecond time resolution were reported for the first time. Two distinct decay pathways, with ∼1 ps and tens of picosecond lifetimes, were observed in 5-AC. Only one decay pathway with 17 ps lifetime was observed in 2,4-DT while an emissive state was found in 2-AT. TDDFT calculations suggest that 5-AC has a dark nπ* (S1) state below the first allowed ππ* (S2) state, which leads to the ultrafast decay of the ππ* state. In 2,4-DT, there is no dark nπ* state below the bright ππ* (S1) state and the 17 ps lifetime is assigned to the relaxation from the ππ* (S1) state to ground state. Two dark nπ* states (S1 and S2) were found in 2-AT, which exhibits much more complex excited state dynamics compared with the other two. Photoluminescence in 2-AT has been confirmed to be fluorescence emission from its bright ππ* (S3) state. Our results strongly suggest that electronic structures are very sensitive to the substitution on the triazine ring and that the photophysical properties of nucleic acid analogues depend highly on their molecular structures.
研究领域:
物理化学
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光化学
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计算化学
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分子光谱学
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核酸类似物
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DOI
高影响因子
MOLECULES
·
2018
·Vol. 23
·期 6
·1440
·
IF 3.098
Haoling Gao,Jiangang Yu,Chengsheng Ge,Qun Jiang
Optically pure sitagliptin phosphate monohydrate is efficiently and practically synthesized through a chiral hemiacetal as the key intermediate in 54% overall yield starting from (E)-4-(2,4,5-trifluorophenyl)but-2-enal andN-boc-protected hydroxylamine. The chiral hemiacetal fragment is constructed by a tandem aza-Michael/hemiacetal reaction catalyzed by an organocatalyst and the influence of acidity of Brønsted acid on tandem aza-Michael/hemiacetal reaction is researched in detail.Keywords:sitagliptin phosphate monohydrate;aza-Michael/hemiacetal reaction;asymmetric synthesis
研究领域:
有机化学
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药物化学
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DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2022
·Vol. 139
·期 32
·e52747
·
IF 3.057
Hao Fu,Shu-ling Gong
Waterborne polyester is a common eco-friendly material in which ester bonds are easy to hydrolyze. Therefore, we synthesized a series of waterborne comb-like polyesters (WCPEs) with hydrophilic side chains through aza-Michael addition under green and mild conditions. The physicochemical structure of the polyesters was verified by 1 H NMR, FTIR, and GPC characterizations. The pH value of dispersions dropped by less than 0.7 after storage for 2 months. The dispersions remained stable after 6 months at room temperature. In addition, the WCPEs exhibited good wetting and dispersing ability for pigment particles as Tego 740 W, which is a mature pigment dispersant product for waterborne coatings. Moreover, the cross-linked WCPEs exhibited excellent chemical resistance, there was only 1.2% weight loss, and almost no mechanism properties decline for cross-linked transparent films even after treatment under an alkaline environment for 20 days. Thus, the synthesized WCPE has potential application as an alkali resistance eco-friendly material, and possesses excellent performance as pigment-dispersion resin.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2023
·
IF 3.6
Yi Li,Yicen Ge,Rui Sun,Xiao Yang,Shipeng Huang,Huajian Dong,Yunyao Liu,Haodan Xue,Xiaoyan Ma,Haiyan Fu,Zeqin Chen
A one-pot cascade reaction for 2,3-dihydropyridinone synthesis was accomplished with 3-fluoro-2-iodo-1-methylpyridinium triflate as the halogen bond catalyst. The desired [4+2] cycloaddition products, bearing aryl, heteroaryl, alkyl, and alicyclic substituents, were successfully furnished in 28–99% yields. Mechanistic investigations proved that a strong halogen-bonding interaction forged between the iodopyridinium catalyst and imine intermediate was essential to dynamically masking the vulnerable C–I bond on the catalyst and accelerating the following aza-Diels–Alder reaction.
研究领域:
有机化学
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催化化学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2025
·
IF 5.6
Ruyi Zhou,Hongxia Tian,Yu Xue,Wen Lv,Mingye Zhu,Jiangang Li,Shujuan Liu,Qiang Zhao
Developing an innovative phototherapy agent that integrates tumor diagnosis and treatment functions is crucial for improving the precision and efficacy of anti-tumor treatment. Traditional aza-dipyrromethene (aza-DP) dyes exhibited strong photothermal effects, high molar absorption coefficients, and good photostability, but their photodynamic effects were weak. Metal elements were introduced into the aza-DP structure to address this issue, thereby enhancing inter-system crossing (ISC) and improving the photodynamic effect. In this study, a series of Zn(II)-chelated aza-DP complexes were designed and synthesized as novel phototherapy agents. To further extend the absorption wavelength of aza-DP in the near-infrared region, strong electron-donating groups of N,N-dimethylaniline were introduced at the 1,7 positions for modification, and both photodynamic and photothermal effects were also improved. The nanoparticles prepared by coating the phototherapy agents as mentioned above with amphiphilic DSPE-mPEG 5000 exhibit excellent hydrophilicity and photostability. Under 660 nm laser irradiation, the nanoparticles exhibited good synergistic therapeutic effects in vivo , with significant anti-tumor effects and minimal accompanying side effects. Meanwhile, considering its excellent photothermal properties, photoacoustic imaging technology was utilized to provide comprehensive guidance for the precise localization of tumors in mice. The study shows that rational modification of traditional aza-DP-based synergistic phototherapy agents can yield unexpected enhancements in their therapeutic effects, providing new ideas for anti-tumor drug development.
研究领域:
药物化学
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生物成像
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光疗
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纳米医学
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肿瘤学
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产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2024
·
IF 5.4
Siao Yang,Xiaoxiao Hu,Zhengze Yong,Qingqing Dou,Cuilu Quan,Hong-Bo Cheng,Mo Zhang,Jing Wang
Photoimmunotherapy represents an innovative approach to enhancing the efficiency of immunotherapy in cancer treatment. This approach involves the fusion of immunotherapy and phototherapy (encompassing techniques like photodynamic therapy (PDT) and photothermal therapy (PTT)). Boron-dipyrromethene (BODIPY) has the potential to trigger immunotherapy owing to its excellent PD and PT efficiency. However, the improvements in water solubility, bioavailability, PD/PT combined efficiency, and tumor tissue targeting of BODIPY require introduction of suitable carriers for potential practical application. Herein, a disulfide bond-based hollow mesoporous organosilica (HMON) with excellent biocompatibility and GSH-responsive degradation properties was used as a carrier to load a bithiophene Aza-BODIPY dye (B5), constructing a sample chemotherapy reagent-free B5@HMON nanoplatform achieving triple-synergistic photoimmunotherapy. HMON, involving disulfide bond , is utilized to improve water solubility, tumor tissue targeting, and PD efficiency by depleting GSH and enhancing host-guest interaction between B5 and HMO. The study reveals that HMON’s large specific surface area and porous properties significantly enhance the light collection and oxygen adsorption capacity. The HMON’s rich mesoporous structure and internal cavity achieved a loading rate of B5 at 11 %. It was found that the triple-synergistic nanoplatform triggered a stronger anti-tumor immune response, including tumor invasion, cytokine production, calreticulin translocation, and dendritic cell maturation, eliciting specific tumor-specific immunological responses in vivo and in vitro . The BALB/c mouse model with 4T1 tumors was used to assess tumor suppression efficiency in vivo , showing that almost all tumors in the B5@HMON group disappeared after 14 days. Such a simple chemotherapy reagent-free B5@HMON nanoplatform achieved triple-synergistic photoimmunotherapy.
研究领域:
癌症治疗
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纳米技术
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生物医学工程
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免疫学
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药学
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产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2020
·Vol. 10
·期 72
·44470-44480
·
IF 3.119
Shu-Xin Pan,Ting-Zheng Xie,Tang-Fu Xiao,Jie-Hui Xie
Thallium (Tl) is a highly toxic heavy metal, and its pollution and remediation in aquatic environments has attracted considerable attention. To reduce or remove Tl pollution in the environment, various strategies have been applied. Graphene oxide (GO) has abundant oxygen-containing functional groups, indicating its high application potential for pollution remediation via methods involving binding to metal ions or positively charged organic molecules or electrostatic interaction and coordination. However, the adsorption of Tl to GO occurs via physical adsorption, for which the adsorption efficiency is low. Therefore, herein, we report a new method to effectively remove Tl pollution in water. We combined GO with aza-crown ether, which enhanced the electronegativity and ability to bind metal ions. The functionalized graphene oxide (FGO) demonstrated high efficiency through a wide pH gradient of 5–10, with a dominant Tl(I) adsorption capacity (112.21 mg g−1) based on the Langmuir model (pH 9.0, adsorbent concentration of 0.8 g L−1). The adsorption of Tl(I) during removal fit a pseudo-second-order kinetic model well. The mechanisms of Tl removal involve physical and chemical adsorption. In summary, our study provides a new method for the detection and treatment of Tl-containing wastewater by using FGO.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
Journal of Innovative Optical Health Sciences
·
2025
·
IF 2.2
Haitao Liao,Qingxuan Meng,Yuhao Li,Senqiang Zhu,Rui Liu,Hongjun Zhu
Optical imaging in vivo holds significant implications for disease diagnosis, and nanoprobes with near-infrared (NIR) emission leverage the deep tissue penetration and high spatiotemporal resolution provided by NIR light, demonstrating considerable application potential. This study presents the design and synthesis of three nitrogen-doped boron–dipyrrin (Aza-BODIPY) molecules: Aza–BDP–OCH 3 , Aza–BDP–OH, and Aza–BDP-I. Leveraging the strong electron-accepting properties of the Aza-BODIPY core, we developed a donor–acceptor–donor (D-A-D) structure for Aza–BDP–OCH 3 through modifications with triphenylamine and methoxy groups, resulting in NIR fluorescence. Aza–BDP–OH was obtained via demethylation using boron tribromide, whereas Aza–BDP-I was synthesized by introducing iodine into Aza–BDP–OCH 3 . These three molecules self-assemble with the amphiphilic polymer PMHC 1 8 -mPEG to form nanoparticles (NPs), yielding optical nanoprobes. The resulting NPs exhibit NIR emission, good water solubility, and biocompatibility. At a concentration of 100 μ g ⋅ mL − 1 , these NPs demonstrate low biological toxicity, highlighting their potential for biological applications. Following tail vein injection, Aza–BDP-I NPs accumulate in tumors and effectively illuminate them via the enhanced permeability and retention (EPR) effect. Furthermore, these organic NPs were metabolized by the liver. Therefore, Aza-BODIPY-based NIR fluorescent NPs offer a promising platform for the development of in vivo optical nanoprobes.
研究领域:
生物医学成像
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纳米技术
·
有机化学
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分子探针
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癌症诊断
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Ning Liu,Ming Zhu,Niu Niu,Jia Ren,Na Yang,Cong Yu
As an important noninvasive tumor treatment method, phototherapy has drawn extensive research interest. However, the requirements of separate excitation wavelengths, high degree of electron–hole recombination, and low reactive oxygen species (ROS) production capability are still the major barriers. This work reports the construction of a novel nanoplatform: design and synthesis of an aza-BODIPY (AB) probe-decorated mesoporous black titanium dioxide (TiO2) (MT) nanoparticles (NPs) for enhanced photodynamic therapy and photothermal therapy under single-wavelength near-infrared (NIR) laser irradiation for the first time. AB probe-decorated MT NPs (abbreviated as MTAB) were synthesized through the Al reduction of mesoporous anatase TiO2 NPs and subsequent adsorption of the AB probe. The mesoporous structure of MT ensured AB loading capacity and avoided the complicated modification and synthesis processes. Heterogeneous MTAB, which possessed staggered energy levels, were assessed for their capability for effective separation of photogenerated electrons and holes for the first time. Upon NIR laser light irradiation, MTAB exhibited sufficient ROS generation, resulting in distinct tumor cell killing and tumor tissue elimination. This unique heterogeneous nanoplatform with staggered energy levels provides a new strategy to enhance ROS generation and improve the therapeutic efficacy.
研究领域:
肿瘤治疗
·
纳米医学
·
光化学
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2020
·Vol. 10
·期 2
·281
·
IF 4.324
Hao-Hua Deng,Xiao-Qiong Shi,Paramasivam Balasubramanian,Kai-Yuan Huang,Ying-Ying Xu,Zhong-Nan Huang,Hua-Ping Peng,Wei Chen
This study puts forward an efficient method for protein detection in virtue of the tremendous fluorescence enhancement property of 6-aza-2-thio-thymine protected gold nanoclusters (ATT-AuNCs). In-depth studies of the protein-induced photoluminescence enhancement mechanism illustrate the mechanism of the interaction between ATT-AuNCs and protein. This new-established probe enables feasible and sensitive quantification of the concentrations of total protein in real samples, such as human serum, human plasma, milk, and cell extracts. The results of this proposed method are in good agreement with those determined by the classical bicinchoninic acid method (BCA method).Keywords:gold nanocluster;6-aza-2-thio-thymine;protein;fluorescence
研究领域:
纳米技术
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分析化学
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生物技术
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）