33402-67-4Relevant articles and documents
Kinetics, Thermodynamics, and Mechanism of the Formation of Benzaldehyde-S(IV) Adducts
Olson, Terese M.,Boyce, Scott D.,Hoffmann, Michael R.
, p. 2482 - 2488 (1986)
The kinetics and mechanism of the formation of α-hydroxyphenylmethanesulfonate (HPMS) by the addition of bisulfite to benzaldehyde were studied at low pH.A three-term rate law was observed as d/dt = (k1α2 + (k2 + k3KH- (H+))α1)t where α1 = ->/, α2 = 2->/, and KH is the proton association constant of benzaldehyde.The rate-limiting steps of each term appeared to be the nucleophilic attack of SO32- on the carbonyl carbon of benzaldehhyde, the attack of HSO3- on the carbonyl carbon, and the attack by HSO3- on the protonated carbon of the carbocation, C6H5C+H(OH), respectively.Over the pH range of most natural systems, only the k1 and k2 steps contribute to adduct formation while the k3 term becomes important for pH 1 = (2.15 +/- 0.09) * 104 M-1 s-1, k2 = (0.71 +/- 0.03) M-1 s-1, k3 ca./= 2.5 * 107 M-1 s-1.Para-substitution on the benzaldehyde ring resulted in a slight increase in reactivity for p-NO2- and p-Cl-, and a decrease for p-OH-, p-OCH3-, and p-CH3-C6H5CHO.The equilibrium association constant, K = ->/-> , at 25 deg C was determined to be 4.8 (+/-0.8) * 103 at μ = 0.1 M and 0.98 (+/-0.11) * 103 M-1 at μ = 1.0 M. ΔH deg and ΔS deg were determined to be -64.6 kJ mol-1 and -146 J mol-1 deg-1, respectively.
1 H -Benzimidazole-5-carboxamidine derivatives: Design, synthesis, molecular docking, DFT and antimicrobial studies
Erol, Meryem,Celik, Ismail,Temiz-Arpaci, Ozlem,Goker, Hakan,Kaynak-Onurdag, Fatma,Okten, Suzan
, p. 21309 - 21317 (2020/12/31)
In this study, 15 new N-(cyclohexyl)-2-substituted-1H-benzimidazole-5-carboxamidine derivatives that could be new antimicrobial agents were synthesized and their antimicrobial activities were determined using the microdilution method. Some of the derivatives showed significant efficacy against MRSA and VREF with an MIC value of 8 μg mL-1 compared to reference drugs. Molecular docking studies of the compounds against PBP4 and active and allosteric regions of PBP2a were performed and estimated ADME profiles were calculated. The nitrogens of the amidine group of M7, one of the most effective antimicrobial compounds compared to reference drugs, formed two separate hydrogen bonds with ASP275 (1.77 ?) and ASP295 (1.83 ?) in the allosteric region of PBP2a. Geometric optimization parameters, MEP analysis, and HUMO and LUMO quantum parameters of M7 were calculated using DFT/B3LYP theory and the 6-311G(d,p) basis set and the results are displayed.
Facile utilisation of aldehyde bisulfite adducts: Synthesis of (E)-1,2- diphenylethenes
Vinay Kumar,Jaganmohan,Sandeep Reddy,Mohanty, Sandeep,Kumar, Jaydeep,Rao, Venkateswara
, p. 109 - 114 (2017/04/03)
Background: A one-pot coupling reaction of aldehyde bisulfite adducts was developed for McMurry reaction using Zn-TiCl4 in 1,4-dioxane solvent medium. The treatment of sodium hydroxy(phenyl)methane sulfonate (2a) with TiCl4 in 1,4-dioxane favoured the deprotection of the bisulfite adduct 2a, and the in situ regeneration of benzaldehyde (1a) underwent reductive coupling to afford stilbene 3a in a relatively good yield, thus leading to an improved synthesis of a series of (E)-1,2- diphenylethenes 3. The present approach provides a new solution to the inherent instability of aldehydes and also provides a direct access to C'C bond formation for the synthesis of 1,2-diphenylethenes from aryl aldehyde bisulfite adducts. Methods: All reactions were performed at 70-80o and the synthesized compounds were characterized by IR, 1H NMR, 13C NMR, and mass spectrometric techniques. Results: The present approach provides a new solution to the instability of aldehydes and also provides a direct access to C'C bond formation for the synthesis of 1,2-diphenylethenes from aryl aldehyde bisulfite adducts. Conclusion: In the present work, we have reported an efficient method for the synthesis of 1,2- diphenylethene derivatives. Aldehydes are commonly used as the starting materials in the McMurry reaction, which affords the stilbene derivatives, the core skeleton of various valuable compounds. To increase the stability of the aldehydes, bisulfite adducts are usually employed, but the deprotection process causes loss of process efficiency. To address this issue, we developed a method based on the single-pot reaction of aromatic bisulfite adduct using TiCl4/Zn in 1,4-dioxane.
