598-31-2Relevant articles and documents
Temperature Coefficients of the Rates of Acid-Catalyzed Enolization of Acetone and Ketonization of Its Enol in Aqueous and Acetonitrile Solutions. Comparison of Thermodynamic Parameters for the Keto-Enol Equilibrium in Solution with Those in the Gas Phase
Chiang, Y.,Kresge, A. J.,Schepp, N. P.
, p. 3977 - 3980 (1989)
Rates of hydrogen ion catalyzed enolization of acetone and ketonization of acetone enol were measured over a range of temperatures in water and in acetonitrile solution.The data give ΔH(excit.) = 20.0 +/- 0.1 kcal mol-1, ΔS(excit.) = -12.1 +/- 0.3 cal K-1 mol-1, and ΔH(excit.) = 20.1 +/- 0.5 kcal mol-1, ΔS(excit.) = -5.8 +/- 1.7 cal K-1 mol-1, for enolization in water and acetonitrile, respectively, and ΔH(excit.) = 9.7 +/- 0.4 kcal mol-1, ΔS(excit.) = -8.6 +/- 1.4 cal K-1 mol-1, and ΔH(excit.) = 11.4 +/- 0.2 kcal mol-1, Σ(excit.) = 1.6 +/-0.8 cal K-1 mol-1, for ketonization in water and acetonitrile, respectively.These values lead to ΔH0 = 10.3 +/- 0.4 kcal mol-1, ΔS0 = -3.5 +/- 1.5 cal K-1 mol-1, for the keto-enol equilibrium in water, and ΔH0 = 8.7 +/- 0.6 kcal mol-1, ΔS0 = -7.4 +/- 1.9 cal K-1 mol-1, for the equilibrium in acetonitrile.This is the first determination of thermodynamic parameters for a simple ketone-enol equilibrium in solution; the results are remarkably similar to the thermodynamic parameters for this reaction in the gas phase.A mechanism involving acid catalysis of the bromination of acetone enol by N-bromosuccinimide, the process used to monitor enolization in acetonitrile solution, is ruled out.
Effect of initial reagent concentrations on the oscillatory behavior of the BZ reaction in a batch reactor
Ganaie, Nadeem B.,Peerzada
, p. 650 - 657 (2009)
A detailed investigation on resorcinol as the Belousov-Zhabotinsky (BZ) oscillator in manganese(II) ion catalyzed reaction system with inorganic bromate (oxidant) and acetone (cosubstrate) was carried out in aqueous sulfuric acid medium (1.3 M). The aforesaid reagents were mixed with various concentrations to evolve the effective concentrations at which the reaction system exhibited better oscillations. The various oscillatory parameters such as time period (t p ), induction period (t in), frequency (v), amplitude (A), and number of oscillations (n) were derived, and the dependence of concentration of the reacting species on these oscillatory parameters was interpreted on the basis of the Field-Koros-Noyes mechanism. 2009 Wiley Periodicals, Inc.
Regioselective reactions on a 1,3-disubstituted dihydroxymethyl or dicarboxyl hexahydropentalene skeleton
T?nase, Constantin I.,Dr?ghici, Constantin,Shova, Sergiu,Cojocaru, Ana,Maganu, Maria,Munteanu, Cristian V.A.,Cocu, Florea
, p. 6852 - 6859 (2015)
Iodo-, bromo-, chloro-etherification and oxymercuration-demercuration of hexahydropentalene 1,3-dimethanol were regioselectively realized with formation of pentalenofurane compounds in good yields. The corresponding hexahydropentaleno diacid and its monoester react regioselectively with MCPBA to give two γ-lactones. Haloetherification of the diacid also regioselectively gives halogenolactones in good yield. A new method for synthesis of a bislactone was developed in better yield (79%) than that presented in the literature (58%).
Induction period in the BrO3 -, Ce(III), H2SO4, oxalic acid and ketone oscillating reaction
Berenstein, Igal,Agreda, Jesus,Barragan, Daniel
, p. 4601 - 4603 (1999)
Contrary to what has been thought, systems classified as bromine- hydrolysis-controlled (BHC) show an induction period. In studies on the effect of a family of ketones upon this type of oscillators, it was found that an induction period appears in an interval of concentrations of the ketone, or in an interval of the value of the enolization constant. Simulations of the processes involved and a corresponding explanation are shown in this paper.
Fluorescent azasteroids through ultrasound assisted cycloaddition reactions
Mangalagiu, Ionel,Moldoveanu, Costel,Zbancioc, Gheorghita
, (2021/08/30)
We report here the synthesis and optical spectral properties of several new azasteroid derivatives. The formation of these compounds was explained based on the most probable mechanism. The luminescent heterocycles were synthesized by 1,3‐dipolar cycloaddition reactions between benzo[f]quinoline and methylpropiolate or dimethyl acetylenedicarboxylate (DMAD). A selective and efficient way for [3+2]‐dipolar cycloaddition of benzo[f]quinolinium ylides under ultrasound (US) irradiation (20 kHz processing frequency) is presented. We report substantially higher yields under US irradiation, whereas the solvent amounts required are at least three‐fold less compared to classical heating. The azasteroid derivatives are blue emitters with λmax of fluorescence around 430–450 nm. A certain influence of the azasteroid substituents concerning absorption and fluorescent properties was observed. Compounds anchored with a bulky pivaloyl group or without a C=O carbonyl group have shown increased fluorescence intensity.
Novel method for synthesizing 1-bromo-2,2-dimethoxypropane
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Page/Page column 4-6, (2020/07/15)
The invention belongs to the technical field of biomedical intermediates, and provides a novel method for synthesizing 1-bromo-2,2-dimethoxypropane, wherein the method comprises the following steps: S1, bromination reaction: dissolving acetone in dichloromethane, preheating to 65 DEG C, adding bromine, controlling the temperature at 65-75 DEG C, and carrying out a reaction for 11-13 h to obtain 1-bromoacetone; S2, carrying out an up-protection reaction: dissolving 1-bromoacetone in methanol, adding trimethyl orthoformate and concentrated hydrochloric acid, and carrying out a reaction for 2-3 hto obtain 1-bromo-2,2-dimethoxypropane. By means of the technical scheme, the problems that in the prior art, hazardous materials are used in a method for synthesizing 1-bromo-2,2-dimethoxypropane, the yield is low, and a product is difficult to purify are solved.
Diastereoselective Synthesis of Z-Alkenyl Disulfides from α-Thiophosphorylated Ketones and Thiosulfonates
Musiejuk, Mateusz,Doroszuk, Justyna,J?drzejewski, Bartosz,Ortiz Nieto, Gregory,Marin Navarro, Marisol,Witt, Dariusz
supporting information, p. 618 - 626 (2019/12/24)
We developed a simple and efficient method for the synthesis of functionalized unsymmetrical Z-alkenyl disulfides under mild conditions in moderate to good yields. The designed method is based on the reaction of α-thiophosphorylated carbonyl compounds with thiotosylates in the presence of a base. The developed method allows the preparation of unsymmetrical Z-alkenyl disulfides bearing additional hydroxy, carboxy, or ester functionalities. (Figure presented.).
Development of triazolothiadiazine derivatives as highly potent tubulin polymerization inhibitors: Structure-activity relationship, in vitro and in vivo study
Ma, Weifeng,Chen, Peng,Huo, Xiansen,Ma, Yufeng,Li, Yanhong,Diao, Pengcheng,Yang, Fang,Zheng, Shengquan,Hu, Mengjin,You, Wenwei,Zhao, Peiliang
, (2020/10/08)
Based on our prior work, we reported the design, synthesis, and biological evaluation of fifty-two new triazolothiadiazine-based analogues of CA-4 and their preliminary structure-activity relationship. Among synthesized compounds, Iab was found to be the most potent derivative possessing IC50 values ranging from single-to double-digit nanomolar in vitro, and also exhibited excellent selectivity over the normal human embryonic kidney HEK-293 cells (IC50 > 100 μM). Further mechanistic studies revealed that Iab significantly blocked tubulin polymerization and disrupted the intracellular microtubule network of A549 cells. Moreover, Iab induced G2/M cell cycle arrest by regulation of p-cdc2 and cyclin B1 expressions, and caused cell apoptosis through up-regulating cleaved PARP and cleaved caspase-3 expressions, and down-regulating of Bcl-2. Importantly, in vivo, Iab effectively suppressed tumor growth of A549 lung cancers in a xenograft mouse model without obvious signs of toxicity, confirming its potential as a promising candidate for cancer treatment.
METHOD OF CONTROLLING PLANTS
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Page/Page column 29, (2018/02/28)
The present invention provides a method of controlling plants comprising applying to the plants, or to the locus of the plants a composition comprising (A) a compound of formula (I) selected from the group consisting of: Formula(I), or an N-oxide or salt form thereof, and (B) one or more further herbicides.
Genetic control of predominantly error-free replication through an acrolein-derived minor-groove DNA adduct
Yoon, Jung-Hoon,Hodge, Richard P.,Hackfeld, Linda C.,Park, Jeseong,Choudhury, Jayati Roy,Prakash, Satya,Prakash, Louise
, p. 2949 - 2958 (2018/02/28)
Acrolein, anα,β-unsaturated aldehyde, is generated in vivo as the end product of lipid peroxidation and from metabolic oxidation of polyamines, and it is a ubiquitous environmental pollutant. The reaction of acrolein with the N2 of guanine in DNA leads to the formation of γ-hydroxy-1-N2-propano-2′ deoxyguanosine (γ-HOPdG), which can exist inDNAin a ring-closed or a ring-opened form. Here, we identified the translesion synthesis (TLS) DNA polymerases (Pols) that conduct replication through the permanently ring-opened reduced form of γ-HOPdG ((r) γ-HOPdG) and show that replication through this adduct is mediated via Rev1/Polη-, Poli/Polκ-, and Polθ- dependent pathways, respectively. Based on biochemical and structural studies, we propose a role for Rev1 and Poli in inserting a nucleotide (nt) opposite the adduct and for Polsη and κ in extending synthesis from the inserted nt in the respective TLS pathway. Based on genetic analyses and biochemical studies with Polθ, we infer a role for Polθ at both the nt insertion and extension steps of TLS. Whereas purified Rev1 and Polθ primarily incorporate a C opposite (r)γ-HOPdG, Poli incorporates a C or a T opposite the adduct; nevertheless, TLS mediated by the Poli-dependent pathway as well as by other pathways occurs in a predominantly error-free manner in human cells. We discuss the implications of these observations for the mechanisms that could affect the efficiency and fidelity of TLS Pols.
