15656-03-8Relevant academic research and scientific papers
Crystal-facet-dependent denitrosylation: Modulation of NO release from S-nitrosothiols by Cu2O polymorphs
Ghosh, Sourav,Roy, Punarbasu,Prasad, Sanjay,Mugesh, Govindasamy
, p. 5308 - 5318 (2019/05/29)
Nitric oxide (NO), a gaseous small molecule generated by the nitric oxide synthase (NOS) enzymes, plays key roles in signal transduction. The thiol groups present in many proteins and small molecules undergo nitrosylation to form the corresponding S-nitrosothiols. The release of NO from S-nitrosothiols is a key strategy to maintain the NO levels in biological systems. However, the controlled release of NO from the nitrosylated compounds at physiological pH remains a challenge. In this paper, we describe the synthesis and NO releasing ability of Cu2O nanomaterials and provide the first experimental evidence that the nanocrystals having different crystal facets within the same crystal system exhibit different activities toward S-nitrosothiols. We used various imaging techniques and time-dependent spectroscopic measurements to understand the nature of catalytically active species involved in the surface reactions. The denitrosylation reactions by Cu2O can be carried out multiple times without affecting the catalytic activity.
Copper(II) activation of nitrite: Nitrosation of nucleophiles and generation of NO by thiols
Kundu, Subrata,Kim, William Y.,Bertke, Jeffery A.,Warren, Timothy H.
supporting information, p. 1045 - 1048 (2017/05/15)
Nitrite (NO2-) and nitroso compounds (E-NO, E = RS, RO, and R2N) in mammalian plasma and cells serve important roles in nitric oxide (NO) dependent as well as NO independent signaling. Employing an electron deficient β-diketiminato copper(II) nitrito complex [C12NNf6]Cu(κ2-O2N)-THF, thiols mediate reduction of nitrite to NO. In contrast to NO generation upon reaction of thiols at iron nitrite species, at copper this conversion proceeds through nucleophilic attack of thiol RSH on the bound nitrite in [CuII](κ2-O2N) that leads to S-nitrosation to give the S-nitrosothiol RSNO and copper(Il) hydroxide [CuII]-OH. This nitrosation pathway is general and results in the nitrosation of the amine Ph2NH and alcohol tBuOH to give Ph2NNO and tBuONO, respectively. NO formation from thiols occurs from the reaction of RSNO and a copper(II) thiolate [CuII]-SR intermediate formed upon reaction of an additional equiv thiol with [CuII]-OH.
Effective optical faraday rotations of semiconductor EuS nanocrystals with paramagnetic transition-metal ions
Hasegawa, Yasuchika,Maeda, Masashi,Nakanishi, Takayuki,Doi, Yoshihiro,Hinatsu, Yukio,Fujita, Koji,Tanaka, Katsuhisa,Koizumi, Hitoshi,Fushimi, Koji
, p. 2659 - 2666 (2013/03/28)
Novel EuS nanocrystals containing paramagnetic Mn(II), Co(II), or Fe(II) ions have been reported as advanced semiconductor materials with effective optical rotation under a magnetic field, Faraday rotation. EuS nanocrystals with transition-metal ions, EuS:M nanocrystals, were prepared by the reduction of the Eu(III) dithiocarbamate complex tetraphenylphosphonium tetrakis(diethyldithiocarbamate)europium(III) with transition-metal complexes at 300 C. The EuS:M nanocrystals thus prepared were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), inductively coupled plasma atomic emission spectroanalysis (ICP-AES), and a superconducting quantum interference device (SQUID) magnetometer. Enhanced Faraday rotations of the EuS:M nanocrystals were observed around 550 nm, and their enhanced spin polarization was estimated using electron paramagnetic resonance (EPR) measurements. In this report, the magneto-optical relationship between the Faraday rotation efficiency and spin polarization is discussed.
