57295-14-4Relevant academic research and scientific papers
Synthesis, characterization and photophysical properties of polyfunctional phenylsilsesquioxanes: [o-RPhSiO1.5]8, [2,5-R 2PhSiO1.5]8, and [R3PhSiO 1.5]8. compounds with the highest number of functional units/unit volume
Sulaiman, Santy,Zhang, Jin,Goodson, Theodore,Laine, Richard M.
, p. 11177 - 11187 (2011)
The availability of pure samples of o-Br8OPS, 2,5-Br 16OPS, and Br24OPS provides a rare opportunity to synthesize sets of corresponding stilbene derivatives: o-RStyr8OPS, RStyr16OPS, and RStyr24OPS where R = 4-methyl (Me), Boc-protected 4-amino (NBoc), or 4-acetoxy (Ace). These derivatives show unique UV-Vis absorption and photoluminescent behavior that points to interesting interactions between the organic tethers and the silsesquioxane cage. o-RStyr8OPS shows blue-shifts in the absorption spectra compared to p-MeStyr8OPS, suggesting that the stilbene groups sit over and interact with the face of the electrophilic silsesquioxane cage as is the case with the parent molecule, o-Br8OPS. The emission spectra of o-RStyr8OPS are similar to p-MeStyr8OPS indicating similar excited states involving the core LUMO. RStyr16OPS exhibits absorption and emission spectra as well as ΦPL similar to 1,4-distyrylbenzene, pointing to disruption in conjugation with the silsesquioxane cage because of steric interactions. RStyr24OPS offers absorption maxima that are blue-shifted and emission maxima that are red-shifted relative to RStyr16OPS. We speculate that RStyr 24OPS is so sterically hindered that interactions with the cage face must occur. NBocStyr24OPS and AceStyr24OPS show moderate ΦPL and high two photon cross-section values, leading us to conclude that there are two excited states of nearly equivalent energy in these molecules with similar decay rates: a normal radiative π-π* transition and charge transfer involving the silsesquioxane cage. These same functional groups can be anticipated to offer much greater two photon absorption if different methods can be found for protecting the free amine from oxidation or replacing the acetoxy group (e.g. perhaps using alkyl or aryl groups).
Synthesis and optical properties of copolymers of 4-aminostyrene with the side styrylquinoline chromophore groups
Goikhman,Subbotina,Martynenkov,Smirnov,Smyslov,Popova,Yakimanskii
, p. 295 - 303 (2011)
Successive molecular assembling in polymer chains furnished a series of the comb-shaped copolymers of 4-aminostyrene containing side styrylquinoline chromophore groups. Thermal, thermomechanical, spectroscopic, and luminescent properties of the polymers a
A ratiometric fluorescent probe for the quantitative detection of styrene in air
Chen, Kai,Gao, Zhenzhong,Sun, Jin,Hou, Xianfeng,Chen, Jian
, p. 13037 - 13039 (2020)
A ratiometric fluorescent probe (N-butyl-4-(4-amino-styryl)-1,8-naphthalimide) was developed for the quantitative detection of styrene in air. The sensing mechanism was found to involve a Heck reaction between the pretreated probe (diazotization) and styr
Optimization of solid-phase extraction (SPE)in the preparation of [18F]D3FSP: A new PET imaging agent for mapping Aβ plaques
Yao, Xinyue,Zha, Zhihao,Zhao, Ruiyue,Choi, Seok Rye,Ploessl, Karl,Liu, Futao,Zhu, Lin,Kung, Hank F.
, p. 54 - 64 (2019)
Introduction: Alzheimer's disease is a common neurodegenerative disease that is characterized by the presence of Aβ plaques in the brain. The FDA has approved the use of Amyvid (florbetapir f18, AV-45)as a PET imaging agent for detecting Aβ plaques in the living human brain. In an attempt to reduce N-demethylation in vivo by taking advantage of more stable C-D bonds, an analog of AV-45, [18F]D3FSP ([18F]7), was synthesized to improve image contrast for detecting and monitoring the Aβ plaques. A convenient and improved preparation of [18F]D3FSP ([18F]7)is needed for widespread clinical application. We report herein the optimization of the radiosynthesis and solid-phase extraction (SPE)procedure. Methods: Radiosyntheses of [18F]D3FSP ([18F]7)under different fluorination conditions were evaluated, and the intermediate, containing an N-Boc protecting group, was deprotected using different acids. One of the major objectives was to simplify the final purification step via SPE to avoid the commonly employed HPLC purification and maximize the radiochemical yields of [18F]D3FSP ([18F]7)while simultaneously removing several chemical impurities (pseudocarriers). Washing various solid-phase cartridges with different combinations of ethanol/water and acetonitrile/water was explored to optimize the purification step. To evaluate the potential interference in Aβ plaques imaging from the presence of pseudocarriers, each chemical was identified and quantified by LC/MS and HPLC. An in vitro binding assay was employed to evaluate the binding affinities of [18F]D3FSP ([18F]7)and the pseudocarriers to Aβ plaques using postmortem AD brain tissue. Results: Using the optimized radiosynthesis method and SPE purification, the final dose of [18F]D3FSP ([18F]7)was obtained in 50 min with a very low content of pseudocarriers (21.7 ± 5.5 μg). The radiochemical yield was 44.4 ± 5.7% (decay corrected), and the radiochemical purity was >95%. SPE-purified doses of [18F]D3FSP ([18F]7)displayed excellent binding affinity and specificity for Aβ plaques as measured in an in vitro binding assay using AD brain homogenates, and the OH-pseudocarrier, 8 (Ki = 19.5 ± 0.5 nM), and the Cl-pseudocarrier, 10 (Ki = 18.6 ± 3.9 nM), showed lower binding affinities for Aβ plaques than those of AV-45 (Ki = 8.6 ± 0.5 nM)and D3FSP, 7 (Ki = 9.8 ± 0.5 nM). Conclusions: An optimized radiosynthesis and fast SPE purification method suitable for the preparation of clinical doses of [18F]D3FSP ([18F]7)was accomplished. The results of quality control tests and binding studies suggested that the SPE-purified doses of [18F]D3FSP ([18F]7)are appropriate for imaging Aβ plaques in the human brain.
Development of polymeric drug delivery system for recognizing vascular endothelial dysfunction
Ikuta, Kenjiro,Mori, Takeshi,Yamamoto, Tatsurhiro,Niidome, Takuro,Shimokawa, Hiroaki,Katayama, Yoshiki
, p. 2811 - 2818 (2008)
The vascular endothelium plays an important role in regulating vascular homeostasis. Damage to the endothelium can lead to cardiovascular diseases such as arteriosclerosis. Therefore, early-stage detection and evaluation of vascular endothelium dysfunction would be very important for effective diagnosis and therapy. We synthesized a polymeric drug carrier bearing an Evans blue analogue as a probing unit for endothelium injury. The polymeric carrier spontaneously formed stable nanoparticles with micelle-like structure in aqueous media and could encapsulate hydrophobic doxorubicin (DOX). The encapsulated DOX showed a sustainable release profile over a period of 10-60 h depending on the loaded DOX concentration. The polymeric carrier specifically adsorbed against the endothelium-injured site in extracted porcine aorta. These properties of the polymeric drug carrier will be suitable for specific drug delivery to endothelium dysfunctional region.
Design of a hybrid biosensor for enhanced phosphopeptide recognition based on a phosphoprotein binding domain coupled with a fluorescent chemosensor
Anai, Takahiro,Nakata, Eiji,Koshi, Yoichiro,Ojida, Akio,Hamachi, Itaru
, p. 6233 - 6239 (2007)
Protein-based fluorescent biosensors with sufficient sensing specificity are useful analytical tools for detection of biologically important substances in complicated biological systems. Here, we present the design of a hybrid biosensor, specific for a bi
Nickel-Catalyzed Reductive Cross-Coupling of Aryl Bromides with Vinyl Acetate in Dimethyl Isosorbide as a Sustainable Solvent
Su, Mincong,Huang, Xia,Lei, Chuanhu,Jin, Jian
supporting information, p. 354 - 358 (2022/01/15)
A nickel-catalyzed reductive cross-coupling has been achieved using (hetero)aryl bromides and vinyl acetate as the coupling partners. This mild, applicable method provides a reliable access to a variety of vinyl arenes, heteroarenes, and benzoheterocycles, which should expand the chemical space of precursors to fine chemicals and polymers. Importantly, a sustainable solvent, dimethyl isosorbide, is used, making this protocol more attractive from the point of view of green chemistry.
The photoredox-catalyzed hydrosulfamoylation of styrenes and its application in the novel synthesis of naratriptan
Chen, Miaomiao,Ding, Xin,Gao, Yongyue,He, Xingxing,Kang, Jin,Lu, Aidang,Wang, Qingmin,Wang, Ziwen,Zhang, Mingjun
supporting information, p. 9140 - 9143 (2021/09/14)
The hydrosulfamoylation of diverse aryl olefins provides facile access to alkylsulfonamides. Here we report a novel protocol utilizing radical-mediated addition and a thiol-assisted strategy to achieve the hydrosulfamoylation of diverse styrenes in modest to excellent yields under mild and economic reaction conditions. The methodology was found to provide an efficient and convenient approach for the synthesis of the anti-migraine drug naratriptan and it also can be used for the late-stage functionalization of natural products or medicines.
Photoinduced Hydrocarboxylation via Thiol-Catalyzed Delivery of Formate across Activated Alkenes
Alektiar, Sara N.,Wickens, Zachary K.
supporting information, p. 13022 - 13028 (2021/09/03)
Herein we disclose a new photochemical process to prepare carboxylic acids from formate salts and alkenes. This redox-neutral hydrocarboxylation proceeds in high yields across diverse functionalized alkene substrates with excellent regioselectivity. This operationally simple procedure can be readily scaled in batch at low photocatalyst loading (0.01% photocatalyst). Furthermore, this new reaction can leverage commercially available formate carbon isotologues to enable the direct synthesis of isotopically labeled carboxylic acids. Mechanistic studies support the working model involving a thiol-catalyzed radical chain process wherein the atoms from formate are delivered across the alkene substrate via CO2?- as a key reactive intermediate.
PRODUCTION METHOD FOR AMIDATE COMPOUND
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Paragraph 0141-0143, (2020/02/13)
A method for producing an amidate compound represented by Formula (3), comprising reacting a urethane compound represented by Formula (1) with a carboxylate compound represented by Formula (2): (in the formulas, A, n, R1, R2, R3, R4, R5, R6, X, and a are as described in the Description).
