29809-25-4Relevant articles and documents
Light-Activated COS/H2S Donation from Photocaged Thiocarbamates
Zhao, Yu,Bolton, Sarah G.,Pluth, Michael D.
, p. 2278 - 2281 (2017)
Hydrogen sulfide (H2S) is an important biomolecule, and responsive chemical tools for its delivery are needed. Here, we utilize the photocleavable o-nitrobenzyl group to unmask caged thiocarbamates and to access photoactivated H2S releasing molecules. These donors function by the initial release of carbonyl sulfide (COS), which is quickly hydrolyzed to H2S by carbonic anhydrase (CA). Our investigations demonstrate that o-nitrobenzyl-caged thiocarbamates can serve as a donor platform for the bio-orthogonal stimulated release of COS/H2S.
Photoresponsive micelles enabling codelivery of nitric oxide and formaldehyde for combinatorial antibacterial applications
Duan, Yutian,He, Kewu,Zhang, Guoying,Hu, Jinming
, p. 2160 - 2170 (2021)
It is of particular interest to develop new antibacterial agents with low risk of drug resistance development and low toxicity toward mammalian cells to combat pathogen infections. Although gaseous signaling molecules (GSMs) such as nitric oxide (NO) and formaldehyde (FA) have broad-spectrum antibacterial performance and the low propensity of drug resistance development, many previous studies heavily focused on nanocarriers capable of delivering only one GSM. Herein, we developed a micellar nanoparticle platform that can simultaneously deliver NO and FA under visible light irradiation. An amphiphilic diblock copolymer of poly(ethylene oxide)-b-poly(4-((2-nitro-5-(((2-nitrobenzyl)oxy)methoxy)benzyl)-(nitroso)amino)benzyl methacrylate) (PEO-b-PNNBM) was successfully synthesized through atom transfer radical polymerization (ATRP). The resulting diblock copolymer self-assembled into micellar nanoparticles without premature NO and FA leakage, whereas they underwent phototriggered disassembly with the corelease of NO and FA. We showed that the NO- and FA-releasing micellar nanoparticles exhibited a combinatorial antibacterial performance, efficiently killing both Gram-negative (e.g., Escherichia coli) and Gram-positive (e.g., Staphylococcus aureus) bacteria with low toxicity to mammalian cells and low hemolytic property. This work provides new insights into the development of GSM-based antibacterial agents.
The early processes in the photochemistry of ortho-nitrobenzyl acetate
Schmierer,Bley,Schaper,Gilch
, p. 363 - 368 (2011)
The early processes in the de-caging of acetic acid from o-nitrobenzyl acetate (oNBAc) were studied by femtosecond techniques. Solutions of oNBAc in acetonitrile were excited by 260 nm laser pulses and the resulting spectroscopic changes probed by transient absorption and stimulated Raman spectroscopy. Absorption and Raman data give evidence of the formation of an aci-nitro species resulting from an intramolecular hydrogen transfer. The species is formed on the 1 ps and 1 ns time scale in equal amounts. The two processes are attributed to hydrogen transfers via a singlet and a triplet channel. The overall quantum yield of the aci-nitro formation is 0.1 matching the de-caging yield.
Phototriggered Release of a Transmembrane Chloride Carrier from an o-Nitrobenzyl-Linked Procarrier
Salunke, Swati Bansi,Malla, Javid Ahmad,Talukdar, Pinaki
supporting information, p. 5354 - 5358 (2019/03/21)
While there have been many studies on synthetic chloride carriers and a recent application for apoptotic cell death, so far, the proposed huge potential of these systems in targeting cancer has not been realized due to their cytotoxicity to healthy cells. Herein, we describe the development of an indole-2-carboxamide receptor as an efficient membrane chloride carrier while the corresponding o-nitrobenzyl-linked derivative is a procarrier of the ion. Photoirradiation of the procarrier in liposomes results in release of the active carrier with up to 90 % transport efficiency. Such photorelease of the carrier also works within cancer cells, resulting in efficient cell killing. Such photocleavable procarriers have great potential as a photodynamic therapy to combat various types of cancers.
Supramolecular photochemistry of encapsulated caged: Ortho -nitrobenzyl triggers
Kamatham, Nareshbabu,Raj, A. Mohan,Givens, Richard S.,Da Silva, José P.,Ramamurthy
, p. 2411 - 2420 (2019/10/21)
ortho-Nitrobenzyl (oNB) triggers have been extensively used to release various molecules of interest. However, the toxicity and reactivity of the spent chromophore, o-nitrosobenzaldehyde, remains an unaddressed difficulty. In this study we have applied the well-established supramolecular photochemical concepts to retain the spent trigger o-nitrosobenzaldehyde within the organic capsule after release of water-soluble acids and alcohols. The sequestering power of organic capsules for spent chromophores during photorelease from ortho-nitrobenzyl esters, ethers and alcohols is demonstrated with several examples.
