5751-48-4Relevant academic research and scientific papers
t-BUTYL LITHIOACETATE ON ORTHO-HYDROXYPHENONES PROVIDING 2-METHYLCHROMONES. AN EASY ACCESS TO KHELLIN
Nagasawa, Kazuo,Kanbara, Hajime,Matsushita, Kazuya,Ito, Keiichi
, p. 1159 - 1162 (1988)
Reaction of t-butyl lithioacetate with several kinds of poly-substituted ortho-hydroxyphenones including khellinone and subsequent acid hydrolysis of the resulting hemiacetals provide the corresponding 2-methylchromone derivatives in excellent overall yields.
A “turn-on” fluorescent probe with high selectivity and large stokes shift for the detection of hydrogen peroxide and its bioimaging applications
Gao, Mengjiao,Hua, Yun,Kang, Yanfei,Li, Jin,Shang, Yajing
supporting information, (2021/09/11)
Hydrogen peroxide (H2O2) plays pivotal roles in various biological functions and pharmacological activities. High selectivity and sensitivity remain challenges for fluorescent probes to detection of H2O2 with a large stokes shift. Herein, a new “turn-on” fluorescent probe (DCM-C) was designed based on the mechanism of intramolecular charge transfer (ICT). In PBS buffer (10 mM, pH 7.4, with 20% DMSO, v/v), DCM-C exhibited high selectivity and sensitivity for H2O2 over other interfering analytes with a large stokes shift (187 nm), and the detection limit was as low as 35.5 nM. In addition, the probe was effective for detecting exogenous and endogenous H2O2 in living cells, and identifying stained in cytoplasm. Moreover, the probe has been used successfully for determining H2O2 in zebrafish by fluorescence imaging.
Access to Chiral Chromenones through Organocatalyzed Mannich/Annulation Sequence
Duan, Jingxiang,Xiong, Zongli,Zhou, Yuqiao,Yao, Weijun,Li, Xiaoyi,Zhang, Min,Wang, Zhen
supporting information, p. 8007 - 8012 (2021/10/20)
Herein we report an efficient and practical method to access chiral chromenones bearing one α-amino stereogenic center in the β position of the carbonyl group. The quinine-derived squaramide could efficiently promote Mannich/cycloketalization/dehydration tandem reactions between 1-(2-hydroxyaryl)-1,3-diketones and functionalized imines generated in situ, providing a wide range of chiral chromenones with propargylamine or α-amino ester moieties with good results (54 examples, up to 98% ee).
A matrix targeted fluorescent probe to monitor mitochondrial dynamics
Ramesh, Madhu,Rajasekhar, Kolla,Gupta, Kavya,Babagond, Vardhaman,Saini, Deepak Kumar,Govindaraju, Thimmaiah
supporting information, p. 801 - 808 (2021/02/09)
Mitochondria are an indispensable organelle for energy production and regulation of cellular metabolism. The structural and functional alterations to mitochondria instigate pathological conditions of cancer, and aging-associated and neurodegenerative disorders. The normal functioning of mitochondria is maintained by quality control mechanisms involving dynamic fission, fusion, biogenesis and mitophagy. Under conditions of mitophagy and neurodegenerative diseases, mitochondria are exposed to different acidic environments and high levels of reactive oxygen species (ROS). Therefore stable molecular tools and methods are required to monitor the pathways linked to mitochondrial dysfunction and disease conditions. Herein, we report a far-red fluorescent probe (Mito-TG) with excellent biocompatibility, biostability, photostability, chemical stability and turn on emission for selective targeting of the mitochondrial matrix in different live cells. The probe was successfully employed for monitoring dynamic processes of mitophagy and amyloid beta (Aβ) induced mitochondrial structural changes.
Design, synthesis, and evaluation of near-infrared fluorescent molecules based on 4h-1-benzopyran core
Li, Chuchu,Lu, Wei,Ma, Mingliang,Tanzeng, Yawen,Wang, Shuting,Zhang, Yuexing,Zhu, Shulei
, (2021/11/30)
A series of novel fluorescent 4H-1-benzopyrans was designed and developed as near-infrared fluorescent molecules with a compact donor–acceptor-donor architecture. Spectral intensity of the fluorescent molecules M-1, M-2, M-3 varied significantly with the increasing polarities of solvents, where M-3 showed high viscosity sensitivity in glycerol-ethanol system with a 3-fold increase in emission intensity. Increasing concentrations of compound M-3 to 5% BSA in PBS elicited a 4-fold increase in fluorescence intensity, exhibiting a superior environmental sensitivity. Furthermore, the in vitro cellular uptake behavior and CLSM assay of cancer cell lines demonstrated that M-3 could easily enter the cell nucleus and bind to proteins with low toxicity. Therefore, the synthesized near-infrared fluorescent molecules could provide a new direction for the development of optical imaging probes and potential further drugs.
Near-infrared compound with aggregation-induced emission property as well as preparation method and application thereof
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Paragraph 0021, (2021/02/10)
The invention discloses a near-infrared compound with an aggregation-induced emission property as well as a preparation method and application of the near-infrared compound. The near-infrared compoundhas high-brightness far-infrared and near-infrared fluorescence emission characteristics, has aggregation-induced emission and crystallization-induced emission characteristics in a near-infrared region, and has the characteristic of aggregation-induced nonlinear optical effect. The nanocrystal can be used for biological imaging and can be prepared into nanocrystals for living body deep high-resolution multi-photon fluorescence and third harmonic imaging. The material synthesized by the method shows the properties of aggregation-induced emission and crystallization-induced emission, while thetraditional fluorescent dye has the phenomenon of aggregation-induced fluorescence quenching under the condition of high concentration, so that the defects of the traditional fluorescent dye are effectively overcome.
Near-infrared hydrazine fluorescence sensor as well as preparation method and application thereof
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Paragraph 0042; 0049; 0052; 0053, (2021/04/21)
The invention discloses a near-infrared hydrazine fluorescence sensor as well as a preparation method and application thereof. According to the method, a target product (E) 4-(2-(4-(dicyanomethylene) chroman-2-yl) vinyl) phenyl 4-bromobutyric acid is synthesized. An ultraviolet-visible spectrophotometer and a fluorescence spectrophotometer are adopted to determine the intensity change of a characteristic peak of a probe in a water phase, so as to determine the existence of hydrazine. The invention provides application of the hydrazine fluorescence sensor in hydrazine detection, and the hydrazine fluorescence sensor can be used for high-selectivity and high-sensitivity detection of hydrazine in a water phase. It is found that thehydrazine fluorescence sensor has a good hydrazine detection effect. Compared with the prior art, the hydrazine fluorescence sensor has the advantages of easily available raw materials, simple synthesis steps, convenient post-treatment, easy realization of large-scale production, and great application prospect in hydrazine detection.
Rational Design of a Highly Selective Near-Infrared Two-Photon Fluorogenic Probe for Imaging Orthotopic Hepatocellular Carcinoma Chemotherapy
Han, Jingjing,Kim, Heejeong,Kwon, Nahyun,Li, Haidong,Qi, Sujie,Wang, Rui,Wu, Xiaofeng,Yoon, Juyoung,Yu, Fabiao
supporting information, p. 15418 - 15425 (2021/06/18)
Selective fluorescence imaging of biomarkers in vivo and in situ for evaluating orthotopic hepatocellular carcinoma (HCC) chemotherapy remains a great challenge due to current imaging agents suffering from the potential interferences of other hydrolases. Herein, we observed that carbamate unit showed a high selectivity toward the HCC-related biomarker carboxylesterase (CE) for evaluation of treatment. A near-infrared two-photon fluorescent probe was developed to not only specially image CE activity in vivo and in situ but also target orthotopic liver tumor after systemic administration. The in vivo signals of the probe correlate well with tumor apoptosis, making it possible to evaluate the status of treatment. The probe enables the imaging of CE activity in situ with a high-resolution three-dimensional view for the first time. This study may promote advances in optical imaging approaches for precise imaging-guided diagnosis of HCC in situ and its evaluation of treatment.
Unusual titanium-induced McMurry coupling of 4-oxo-4H-chromene-2-carbaldehydes enroute to bis-chromones
Yerrabelly, Jayaprakash Rao,Bathini, Pavan Kumar,Yerrabelly, Hemasri,Vadapalli, Kishore
, p. 4705 - 4709 (2021/03/22)
Ti/Zn-mediated McMurry coupling of a series of 4-oxo-4H-chromene-2-carbaldehydes afforded unusual chemoselective CH2-CH2tethered bis-chromones. Studying the reaction parameters and reagents further confirmed that the formation of unexpected coupled products is selective to 4-oxo-4H-chromene-2-carbaldehydes. This methodology demonstrated a simple and efficient route for the synthesis of bis-chromones.
Divergent synthesis of flavones and flavanones from 2′-hydroxydihydrochalconesviapalladium(ii)-catalyzed oxidative cyclization
Son, Seung Hwan,Cho, Yang Yil,Yoo, Hyung-Seok,Lee, Soo Jin,Kim, Young Min,Jang, Hyu Jeong,Kim, Dong Hwan,Shin, Jeong-Won,Kim, Nam-Jung
, p. 14000 - 14006 (2021/04/22)
Divergent and versatile synthetic routes to flavones and flavanonesviaefficient Pd(ii) catalysis are disclosed. These Pd(ii) catalyses expediently provide a variety of flavones and flavanones from 2′-hydroxydihydrochalcones as common intermediates, depending on oxidants and additives,viadiscriminate oxidative cyclization sequences involving dehydrogenation, respectively, in a highly atom-economic manner.
