119137-07-4Relevant articles and documents
Synthesis and photochemical studies of 2-nitrobenzyl-caged N-hydroxysulfonamides
Zhou, Yang,Bharadwaj, Vinay,Rahman, Mohammad S.,Sampson, Paul,Brasch, Nicola E.,Seed, Alexander J.
, (2019)
Recently, N-hydroxysulfonamides (RSO2NHOH) caged by photolabile protecting groups have attracted significant interest as potential photoactive nitroxyl (HNO) donors. The selectivity of the desired HNO generation pathway from photocaged N-hydroxysulfonamides versus a competing pathway involving O-N bond cleavage is dependent on the specific photodeprotection mechanism of the phototrigger. We present a new class of photocaged N-hydroxysulfonamides incorporating the well-established o-nitrobenzyl photoprotecting group, including a derivative incorporating an additional carbonate linker. Photodecomposition of o-NO2Bn-ON(H)SO2CF3 and the corresponding 2-nitro-4,5-dimethoxybenzyl analog generated the desired HNO and CF3SO2- as a minor pathway, with competing photoinduced O-N bond cleavage to release CF3SO2NH2 as the major photodecomposition pathway. Photolysis of the corresponding -SO2CH3 analogs resulted in O-N bond cleavage only. The presence of the o-nitro substituent was shown to be essential for photoactivity. Photorelease of the parent HNO donor CH3SO2NHOH was observed as the major product upon irradiation of o-NO2Bn-OC(O)ON(H)SO2CH3, with the desired HNO release and O-N bond cleavage occurring as minor pathways. Photoproduct quantum yields for each species have been determined by actinometry. The effect of solvent, pH and air on the mechanism of photodecomposition was studied for o-NO2Bn-ON(H)SO2CH3. The ratio of the solvents in the solvent mixture (CH3CN and phosphate buffer, pH 7.0), the pH of the aqueous component of the buffer, and the presence of oxygen did not affect the amount of each photoproduct and the observed rate constant for O-N bond cleavage. Possible mechanisms for the various pathways are proposed.
One- and two-photon responsive sulfur dioxide (SO2) donors: a combinatorial drug delivery for improved antibiotic therapy
Venkatesh, Yarra,Kiran, Kumari Shanti,Shah, Sk. Sheriff,Chaudhuri, Amrita,Dey, Satyahari,Singh, N. D. Pradeep
, p. 2640 - 2645 (2019)
One- and two-photon activated sulfur dioxide donors based on a 4,5-dimethoxy-2-nitrobenzyl phototrigger have been developed. The designed donors have the ability to release not only SO2 but also a hydroxy-compound in a simultaneous manner. Furthermore, we demonstrated their application in combinatorial therapy by the dual release of SO2 and an active drug, i.e. ferulic acid ethyl ester (FAEE) with self-monitoring ability. Next, we investigated the in vitro cellular uptake and the capability of SO2 generation from the donors using a well-known coumarin-hemicyanine fluorescent probe. Finally, we evaluated the antibacterial activity of the designed donors (5a, 5b and 6) by broth dilution and agar well diffusion methods on E. cloacae cells (MTCC 509). The results show that the donor 5a exhibits enhanced antibacterial efficacy compared to 5b and 6, due to the synergetic effect of dually released SO2 and FAEE.
Engineered Th17 Cell Differentiation Using a Photoactivatable Immune Modulator
Chang, Pamela V.,Parasar, Bibudha
, p. 18103 - 18108 (2020)
T helper 17 (Th17) cells, an important subset of CD4+ T cells, help to eliminate extracellular infectious pathogens that have invaded our tissues. Despite the critical roles of Th17 cells in immunity, how the immune system regulates the production and maintenance of this cell type remains poorly understood. In particular, the plasticity of these cells or their dynamic ability to trans-differentiate into other CD4+ T cell subsets remains mostly uncharacterized. Here, we report a synthetic immunology approach using a photoactivatable immune modulator (PIM) to increase Th17 cell differentiation on demand with spatial and temporal precision to help elucidate this important and dynamic process. In this chemical strategy, we developed a latent agonist that upon photochemical activation releases a small-molecule ligand that targets the aryl hydrocarbon receptor (AhR) and ultimately induces Th17 cell differentiation. We used this chemical tool to control AhR activation with spatiotemporal precision within cells and to modulate Th17 cell differentiation on demand using UV light illumination. We envision that this approach will enable an understanding of the dynamic functions and behaviors of Th17 cells in vivo during immune responses and in mouse models of inflammatory disease.
Fluorescence photoactivation by ligand exchange around the boron center of a BODIPY chromophore
Shaban Ragab, Sherif,Swaminathan, Subramani,Deniz, Erhan,Captain, Burjor,Raymo, Francisco M.
, p. 3154 - 3157 (2013)
Chelation of the boron center of the borondipyrromethene (BODIPY) platform by a catecholate ligand results in effective fluorescence suppression. Electron transfer from the chelating unit to the adjacent chromophore upon excitation is responsible for fluorescence quenching. Under the influence of a photoacid generator, the catecholate chelator can be exchanged with a pair of methoxide ligands. This photoinduced transformation prevents electron transfer and efficiently activates the fluorescence of the BODIPY chromophore.
Caged Naloxone: Synthesis, Characterization, and Stability of 3- O -(4,5-Dimethoxy-2-nitrophenyl)carboxymethyl Naloxone (CNV-NLX)
Lewin, Anita H.,Fix, Scott E.,Zhong, Desong,Mayer, Louise D.,Burgess, Jason P.,Mascarella, S. Wayne,Reddy, P. Anantha,Seltzman, Herbert H.,Carroll, F. Ivy
, p. 563 - 567 (2018)
The photolabile analogue of the broad-spectrum opioid antagonist naloxone, 3-O-(4,5-dimethoxy-2-nitrophenyl)carboxymethyl naloxone (also referred to as "caged naloxone", 3-O-(α-carboxy-6-nitroveratryl)naloxone, CNV-NLX), has been found to be a valuable biochemical probe. While the synthesis of CNV-NLX is simple, its characterization is complicated by the fact that it is produced as a mixture of αR,5R,9R,13S,14S and αS,5R,9R,13S,14S diastereomers. Using long-range and heteronuclear NMR correlations, the 1H NMR and 13C NMR resonances of both diastereomers have been fully assigned, confirming the structures. Monitoring of solutions of CNV-NLX in saline buffer, in methanol, and in DMSO has shown CNV-NLX to be stable for over a week under fluorescent laboratory lights at room temperature. Exposure of such solutions to λ 365 nm from a hand-held UV lamp led to the formation of naloxone and CNV-related breakdown products.
One- And Two-Photon-Activated Cysteine Persulfide Donors for Biological Targeting
Chaudhuri, Amrita,Venkatesh, Yarra,Das, Joyjyoti,Gangopadhyay, Moumita,Maiti, Tapas K.,Singh, N. D. Pradeep
, p. 11441 - 11449 (2019)
Persulfides have been considered as potential signaling compounds similar to the H2S in "S-persulfidation", a sulfur-mediated redox cycle. The research of this sulfur-mediated species is hindered because of the lack of efficient persulfide donors. In this current study, we have developed one- and two-photon-activated persulfide donors based on an o-nitrobenzyl (ONB) phototrigger, which releases the biologically active persulfide (N-acetyl l-cysteine persulfide, NAC-SSH) in a spatiotemporal manner. Next, we have demonstrated the detection of persulfide release both qualitatively and quantitatively using the well-known "turn on" fluorescence probe, that is, monobromobimane, and the trapping agent, that is, 2,4-dinitrofluorobenzene, respectively. Furthermore, we examined the cytotoxicity of synthesized persulfide donors on HeLa cells and the cytoprotective ability in the highly oxidizing cellular environment.
