31005-03-5Relevant articles and documents
Photo-switchable nanoporous silica supports for controlled drug delivery
Zeleňák, Vladimír,Beňová, Eva,Almá?i, Miroslav,Halamová, Dá?a,Hornebecq, Virginie,Hronsky, Viktor
, p. 13263 - 13271 (2018)
A photo-responsive ligand 7-[(3-triethoxysilyl)propoxy]coumarin (C) was grafted on the surface of a mesoporous silica SBA-12 material. The obtained functionalized support SBA-12_C was used as an effective light-controlled storage/release system of the anti-inflammatory drug naproxen. Irradiation with UV light at 365 nm induces the photo-dimerization of the coumarin on the surface, giving a dimer connected by a cyclobutane ring, leading to pore closure. However, irradiation with UV light of a shorter wavelength, 254 nm, leads to the cleavage of the dimers, opening of the pores, and the guest drug molecules can be released from the pores. The release of the drug was studied in two types of media, a simulated body fluid at pH = 7 and a simulated gastric fluid at pH = 2. The prepared materials were characterized by high resolution transmission electron microscopy (HR-TEM), nitrogen adsorption/desorption, infrared spectroscopy (FT-IR), thermoanalytical methods (TG/DTA) and liquid and solid-state NMR spectroscopy. The amount of released drug was monitored by HPLC chromatography at defined time intervals. The samples with pores closed by coumarin dimers were tight enough to show premature release of the drug from the sample. After light-driven pore opening, the amounts of released naproxen from coumarin modified mesoporous silica were different, depending on the pH conditions of the release media.
A novel class of inhibitors for steroid 5α-Reductase: Synthesis and evaluation of umbelliferone derivatives
Fan, Gao-jun,Mar, Woongchon,Park, Man Ki,Wook Choi, Eun,Kim, Kinam,Kim, Sanghee
, p. 2361 - 2363 (2001)
A series of umbelliferone derivatives was prepared and their 5α-reductase type 1 inhibitory activities were evaluated in cell culture systems. Our studies have identified a new series of potent 5α-reductase type 1 inhibitors and provided the basis for further development for the treatment of human endocrine disorders associated with overproduction of DHT by 5α-reductase type 1. The preliminary structure-activity relationship was described to elucidate the essential structural requirements.
SESEBRINIC ACID, A CINNAMIC ACID DERIVATIVE FROM SESELI SIBIRICUM
Banerjee, Sunil K.,Mukhopadhyay, Sibabrata,Gupta, Bishan D.,Singh, Kuber,Raj, Som
, p. 1817 - 1820 (1987)
A new cinnamic acid, sesebrinic acid, was isolated from the aerial parts of Seseli sibiricum; its structure was elucidated by chemical and spectral data and hemisynthesis.A number of its analogues were also synthesized. - Key Word Index: Seseli sibiricum; Umbelliferae; coumarins; sesebrinic acid; synthesis.
A minor structure modification serendipitously leads to a highly carbapenemase-specific fluorogenic probe
Wang, Jie,Xie, Hexin,Xu, Weipan,Xue, Shuyuan,Yu, Tao
, p. 4029 - 4033 (2020)
Reported herein is a fluorogenic probe for the detection of carbapenemase activity. This reagent features carbapenem as an enzyme recognition motif and a carbon-carbon double bond between carbapenem and the fluorophore, exhibiting high specificity to all carbapenemases, including metallo carbapenemases and serine carbapenemases, over other β-lactamases.
Realizing both selective adsorption and efficient regeneration using adsorbents with photo-regulated molecular gates
Zhu, Jing,Ding, Jia-Jia,Liu, Xiao-Qin,Tan, Peng,Sun, Lin-Bing
, p. 4006 - 4009 (2016)
A new generation of smart adsorbents was designed by grafting photo-responsive molecules onto the pore entrances of mesoporous silica. These molecules act as the gates of the mesopores, which are reversibly closed/opened upon light irradiation. Our smart adsorbents thus realize both selective adsorption and efficient desorption, which is highly expected for adsorption but impossible for traditional adsorbents with fixed pore entrances.
Multi-cycle reversible control of gas permeability in thin film composite membranesviaefficient UV-induced reactions
Alrayyes, Abdalrahman U.,Low, Ze-Xian,Wang, Huanting,Saito, Kei
, p. 3391 - 3394 (2021)
This communication presents a new, UV-induced mechanism to reversibly control the permeability of ultra-thin polymer coatings. Photoreversible [2+2] cycloaddition reactions were utilised to adjust the crosslinking degree and glass transition temperature of a coating. Consequently, a 300%, reversible change in the coating's oxygen permeability was achieved without loss of performance. Ultimately, the findings demonstrate the capability of using low UV doses to reversibly and efficiently regulate mass transport through ultra-thin coatings fabricated in a facile manner.
A fluorogenic assay for transketolase from Saccharomyces cerevisiae
Sevestre, Aurélie,Hélaine, Virgil,Guyot, Ghislain,Martin, Christine,Hecquet, Laurence
, p. 827 - 830 (2003)
In order to generate transketolase (TK) with new or improved properties by in vitro evolution, an efficient screening system is an absolute prerequisite for identifying the evolved enzyme variants. We report here an assay allowing us to detect wild type TK activity in vitro by fluorescence. We examined the use of the fluorogenic compound 1 as donor substrate of TK, which is itself non fluorescent but releases a fluorescent product: umbelliferone.
A new synthesis of angelicin from 7-hydroxycoumarin via c-propenation-o-vinylation and ring-closing metathesis
Tsai, Tzu-Wei,Wang, Eng-Chi
, p. 1019 - 1023 (2004)
A new and concise method for the synthesis of angelicin was described. 7-Hydroxycoumarin was converted into angelicin in good overall yields via the process of c-propenation-o-vinylation and ring-closing metathesis (RCM).
Photoresponsive cellulose paper as a molecular printboard for covalent printing
Rull-Barrull,D'Halluin,Le Grognec,Felpin
, p. 5154 - 5162 (2017)
This contribution unveils and defines the concept of covalent printing onto cellulose paper through the support of a simple and efficient strategy. A photoresponsive cellulose paper bearing disulfide functional groups was created as a molecular printboard for spatio-temporal writing through thiol-X ligation of functional inks upon light irradiation. This strategy using molecular inks in a modular way culminated with the creation of patterns with a high resolution. Hidden covalent writing to the naked eyes was developed through the use of coumarin-based inks while the use of colored inks containing a rhodamine backbone established an uncovered pH-responsive covalent printing, both strategies can potentially find applications in the formation of anti-counterfeiting devices.
On the possibility of tuning molecular edges to direct supramolecular self-assembly in coumarin derivatives through cooperative weak forces: Crystallographic and hirshfeld surface analyses
Seth, Saikat Kumar,Sarkar, Debayan,Jana, Atish Dipankar,Kar, Tanusree
, p. 4837 - 4849 (2011)
Four organic compounds based on substituted coumarin derivatives (1 - 4) have been synthesized and characterized by X-ray structural studies with a detailed analysis of Hirshfeld surface and fingerprint plots facilitating a comparison of intermolecular interactions in building different supramole-cular architectures. The X-ray study reveals that in the molecular packing C - H · · ·O, π · · · π, and carbonyl (lone pair) · · · π interactions cooperatively take part. The recurring feature of the self-assembly in all the compounds is the appearance of the molecular ribbon through weak hydrogen bonding. These hydrogen bonded ribbons further stacked into molecular layers by π · · · π forces. The mode of cooperativity of the weak C - H · · · O and π · · · π forces is such that they operate in mutuallyperpen-dicular directions - hydrogen bonding in the plane of the molecule at their edges and π-stacking perpendicular to the molecular plane. Investigation of intermolecular interactions and crystal packing via Hirshfeld surface analyses reveals that more than two-thirds of the close contacts are associated with weak interactions. Hirshfeld surface and breakdown of the corresponding fingerprint plots of four coumarin structures clearly quantify the interactions within the crystal structures, revealing significant similarities in the interactions experienced by each compound. The binding energies associated with the weak interactions have been estimated using density functional theory calculations.
