77337-82-7Relevant articles and documents
Preparation method for 2,5-dibromophenol
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Paragraph 0011; 0012; 0016; 0017, (2019/02/21)
The invention discloses an industrial preparation method for 2,5-dibromophenol. The industrial preparation method for the 2,5-dibromophenol comprises the following steps: using 2-amino-5-nitrobenzenemethyl ether as an initial raw material, and synthesizing the 2,5-dibromophenol through a four-step reaction of performing diazotization bromination, reduction, secondary diazotization bromination anddemethylation. The obtained 2,5-dibromophenol is a black solid, the purity is 97.5%, a raw material conversion rate in each step reaches 100% respectively, and a total yield of the whole process reaches 34%.
Development of 2-thioxoquinazoline-4-one derivatives as dual and selective inhibitors of dynamin-related protein 1 (Drp1) and puromycin-sensitive aminopeptidase (PSA)
Numadate, Akiyoshi,Mita, Yusuke,Matsumoto, Yotaro,Fujii, Shinya,Hashimoto, Yuichi
, p. 979 - 988 (2015/02/19)
An established inhibitor ot dynamin-related protein 1 (Drp1), 3-(2,4-dichloro-5-methoxyphenyl)- 2- thioxoquinazoline-4-one (mdivi-1), was recently reported also to show potent puromycin-sensitive aminopeptidase (PSA)-inhibitory activity. Herein, we report structural development of mdivi-1 derivatives and structure-activity relationship (SAR) analysis of the synthesized compounds, as well as the structurally related PSA-specific inhibitor 3-(2,6-diethylphenyl)quinazoline-2,4-dione (PAQ-22), with the aim of identifying key structural features for inhibitory activity in order to develop selective inhibitors of Drpl, which is a potential target for treatment of Huntington's disease. Among the synthesized compounds, 3-(4-chloro3methoxyphenyl)-2-thioxoquinazoline-4-one 10g) exhibited more potent Drpl-inhibitory activity than mdivi-1 with high selectivity for Drpl over PSA.
On the mechanism of the initiation reaction in Grubbs-Hoveyda complexes
Thiel, Vasco,Hendann, Marina,Wannowius, Klaus-Juergen,Plenio, Herbert
experimental part, p. 1104 - 1114 (2012/03/12)
Grubbs-Hoveyda-type complexes with variable 4-R (complexes 1: 4-R = NEt2, OiPr, H, F, NO2) and 5-R substituents (complexes 2: 5-R = NEt2, OiPr, Me, F, NO2) at the 2-isopropoxy benzylidene ether ligand and with variable 4-R substituents (complexes 3: 4-R = H, NO2) at the 2-methoxy benzylidene ether ligand were synthesized and the respective Ru(II/III) redox potentials (ranging from ΔE = +0.46 to +1.04 V), and UV-vis spectra recorded. The initiation kinetics of complexes 1-3 with the olefins diethyl diallyl malonate (DEDAM), butyl vinyl ether (BuVE), 1-hexene, styrene, and 3,3-dimethylbut-1-ene were investigated using UV-vis spectroscopy. Electron-withdrawing groups at the benzylidene ether ligands were found to increase the initiation rates, while electron-donating groups lead to slower precatalyst activation; accordingly with DEDAM, the complex 1(NO 2) initiates almost 100 times faster than 1(NEt2). The 4-R substituents (para to the benzylidene carbon) were found to have a stronger influence on physical and kinetic properties of complexes 1 and 2 than that of 5-R groups para to the ether oxygen. The DEDAM-induced initiation reactions of complexes 1 and 2 are classified as two-step reactions with an element of reversibility. The hyperbolic fit of the kobs vs [DEDAM] plots is interpreted according to a dissociative mechanism (D). Kinetic studies employing BuVE showed that the initiation reactions simultaneously follow two different mechanistic pathways, since the kobs vs [olefin] plots are best fitted to kobs = kD·k4/k -D·[olefin]/(1 + k4/k-D·[olefin]) + kI·[olefin]. The kI·[olefin] term dominates the initiation behavior of the sterically less demanding complexes 3 and was shown to correspond to an interchange mechanism with associative mode of activation (Ia), leading to very fast precatalyst activation at high olefin concentrations. Equilibrium and rate constants for the reactions of complexes 1-3 with the bulky PCy3 were determined. In general, sterically demanding olefins (DEDAM, styrene) and Grubbs-Hoveyda type complexes 1 and 2 preferentially initiate according to the dissociative pathway; for the less bulky olefins (BuVE, 1-hexene) and complexes 1 and 2 both D and I a are important. Activation parameters for BuVE reactions and complexes 1(NEt2), 1(H), and 1(NO2) were determined, and ΔS? was found to be negative (ΔS ? = -113 to -167 J·K-1·mol -1) providing additional support for the Ia catalyst activation.
