Correction to “Catalytic C(β)–O Bond Cleavage of Lignin in a One-Step Reaction Enabled by a Spin-Center Shift”

We report a mechanism of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) conversion by the mammalian type V adenylyl cyclase revealed in molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) simulations. We characterize a set of computationally derived enzyme-substrate (ES) structures showing an important role of coordination shells of magnesium ions in the solvent accessible active site. Several stable six-fold coordination shells of MgA2+ are observed in MD simulations of ES complexes. In the lowest energy ES conformation, the coordination shell of MgA2+ does not include the Oδ1 atom of the conserved Asp440 residue. Starting from this conformation, a one-step reaction mechanism is characterized which includes proton transfer from the ribose O3'H3' group in ATP to Asp440 via a shuttling water molecule and PA-O3A bond cleavage and O3'-PA bond formation. The energy profile of this route is consistent with the observed reaction kinetics. In a higher energy ES conformation, MgA2+ is bound to the Oδ1(Asp440) atom as suggested in the relevant crystal structure of the protein with a substrate analog. The computed energy profile initiated by this ES is characterized by higher energy expenses to complete the reaction. Consistently with experimental data, we show that the Asp440Ala mutant of the enzyme should exhibit a reduced but retained activity. All considered reaction pathways include proton wires from the O3'H3' group via shuttling water molecules.

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Rapid phosphorus–carbon bond cleavage in bis(diphenylphosphino)methane under very mild conditions: a one-step synthesis of µ-PPh2, µ-Ph2PCH2PPh2binuclear CoIand NiIcarbonyls directly from CoIIand NiIIsalts

Journal of the Chemical Society Chemical Communications ◽

10.1039/c39900000032 ◽

1990 ◽

pp. 32-33 ◽

Cited By ~ 15

Author(s):

David J. Elliot ◽

David G. Holah ◽

Alan N. Hughes ◽

Hameed A. Mirza ◽

Elizabeth Zawada

Keyword(s):

Bond Cleavage ◽

Carbon Bond ◽

Mild Conditions ◽

One Step

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One-step synthesis and P–H bond cleavage reactions of the phosphanyl complex syn-[MoCp{PH(2,4,6-C6H2tBu3)}(CO)2] to give heterometallic phosphinidene-bridged derivatives

Dalton Transactions ◽

10.1039/c9dt02382h ◽

2019 ◽

Vol 48 (39) ◽

pp. 14585-14589

Author(s):

M. Angeles Alvarez ◽

Mónica Burgos ◽

M. Esther García ◽

Daniel García-Vivó ◽

Miguel A. Ruiz ◽

...

Keyword(s):

Bond Cleavage ◽

Title Complex ◽

One Step ◽

Cleavage Reactions ◽

Electron Reduction

Photolysis, deprotonation and one-electron reduction enable the title complex to render new phosphinidene derivatives with heterometallic Mo–P–M cores (M = Re, Fe, Au).

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ChemInform Abstract: Spin-Center Shift Reactions

ChemInform ◽

10.1002/chin.201238269 ◽

2012 ◽

Vol 43 (38) ◽

pp. no-no

Author(s):

Pablo Wessig

Keyword(s):

Center Shift ◽

Spin Center

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Proton-Coupled Electron Transfer in the Reaction of 3,4-Dihydroxyphenylpyruvic Acid with Reactive Species in Various Media

International Journal of Chemical Physics ◽

10.1155/2015/835707 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 4

Author(s):

J. J. Fifen ◽

Z. Dhaouadi ◽

M. Nsangou ◽

O. Holtomo ◽

N. Jaidane

Keyword(s):

Electron Transfer ◽

Proton Transfer ◽

Activation Barrier ◽

Bond Cleavage ◽

Hydrogen Atom Transfer ◽

Free Energies ◽

Solvent Interactions ◽

Proton Coupled Electron Transfer ◽

Nonpolar Solvents ◽

One Step

The distinction of concerted proton-coupled electron transfer (CPCET) from sequential one as well as proton transfer-electron transfer (PT-ET) from electron transfer-proton transfer (ET-PT) in the O–H bond cleavage reactions in various media has always been a difficult task. In this work, the activation barrier of the CPCET mechanism, its rate constants, and reaction free energies related to ET-PT and PT-ET involving coreactive species were presented as good parameters to attempt the problem. DFT calculations were carried out studying the described pathways subsequent to the scavenging of OH• and OBr- by the 3,4-DHPPA in various media. The solvation was described in a hybrid manner using IEF-PCM model conjointly with a model that takes into account some solute-solvent interactions. As a result, we found that the scavenging of hydroxyl radical by 3,4-DHPPA is thermodynamically governed by a one-step hydrogen atom transfer (CPCET) from the acid to the radical in all media. In kinetic viewpoint, CPCET still dominates in the vacuum and in nonpolar solvents, but in polar solvents it could compete strongly with the ET-PT mechanism so that the latter could slightly dominate.

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Spin-Center Shift-Enabled Direct Enantioselective α-Benzylation of Aldehydes with Alcohols

Journal of the American Chemical Society ◽

10.1021/jacs.7b12768 ◽

2018 ◽

Vol 140 (9) ◽

pp. 3322-3330 ◽

Cited By ~ 44

Author(s):

Eric D. Nacsa ◽

David W. C. MacMillan

Keyword(s):

Center Shift ◽

Spin Center

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Mechanisms of ATP to cAMP Conversion Catalyzed by the Mammalian Adenylyl Cyclase: A Role of Magnesium Coordination Shells and Proton Wires

10.26434/chemrxiv.9209180.v1 ◽

2019 ◽

Author(s):

Bella Grigorenko ◽

Igor Polyakov ◽

Alexander Nemukhin

Keyword(s):

Adenylyl Cyclase ◽

Bond Cleavage ◽

Cyclic Adenosine Monophosphate ◽

Adenosine Monophosphate ◽

Md Simulations ◽

Coordination Shell ◽

Energy Profile ◽

One Step ◽

Type V

We report a mechanism of adenosine triphosphate (ATP) to cyclic adenosine monophosphate (cAMP) conversion by the mammalian type V adenylyl cyclase revealed in molecular dynamics (MD) and quantum mechanics/molecular mechanics (QM/MM) simulations. We characterize a set of computationally derived enzyme-substrate (ES) structures showing an important role of coordination shells of magnesium ions in the solvent accessible active site. Several stable six-fold coordination shells of MgA2+ are observed in MD simulations of ES complexes. In the lowest energy ES conformation, the coordination shell of MgA2+ does not include the Oδ1 atom of the conserved Asp440 residue. Starting from this conformation, a one-step reaction mechanism is characterized which includes proton transfer from the ribose O3'H3' group in ATP to Asp440 via a shuttling water molecule and PA-O3A bond cleavage and O3'-PA bond formation. The energy profile of this route is consistent with the observed reaction kinetics. In a higher energy ES conformation, MgA2+ is bound to the Oδ1(Asp440) atom as suggested in the relevant crystal structure of the protein with a substrate analog. The computed energy profile initiated by this ES is characterized by higher energy expenses to complete the reaction. Consistently with experimental data, we show that the Asp440Ala mutant of the enzyme should exhibit a reduced but retained activity. All considered reaction pathways include proton wires from the O3'H3' group via shuttling water molecules.

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Sulfuryl Fluoride Promoted Thiocyanation of Alcohols: A Practical Method for Preparing Thiocyanates

Synlett ◽

10.1055/s-0040-1707151 ◽

2020 ◽

Vol 31 (14) ◽

pp. 1413-1417

Author(s):

Chengrong Ding ◽

Guofu Zhang ◽

Lidi Xuan ◽

Yiyong Zhao

Keyword(s):

Ethyl Acetate ◽

Functional Group ◽

High Efficiency ◽

Bond Cleavage ◽

Ammonium Thiocyanate ◽

Practical Method ◽

Sulfuryl Fluoride ◽

Mild Conditions ◽

One Step ◽

The One

A novel SO2F2-promoted thiocyanation method for the one-step synthesis of thiocyanates through C–O bond cleavage of readily available alcohols with ammonium thiocyanate as the thiocyanating agent was developed. The method avoids the use of additional catalyst, and a variety of (hetero)arene, alkene and aliphatic alcohols reacted with high efficiency in ethyl acetate under mild conditions to afford the corresponding thiocyanates in excellent to quantitative yields with broad functional-group compatibility.

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