THE HYDROLYSIS OF PHOSPHATE DIESTERS WITH BARIUM HYDROXIDE

1955 ◽  
Vol 33 (4) ◽  
pp. 705-710 ◽  
Author(s):  
C. W. Helleiner ◽  
G. C. Butler

The rate of alkaline hydrolysis of diphenyl phosphate has been found to be increased by the presence of barium. Similarly, desoxyribonucleate (DNA), which is not hydrolyzed rapidly by hot sodium hydroxide, is hydrolyzed by barium hydroxide. Only a very small proportion of the total phosphorus of either diphenyl phosphate or DNA is converted to inorganic phosphate during this hydrolysis. In addition to hydrolysis of the phosphate ester bonds of DNA, hot alkali also causes the deamination of desoxycytidylic acid residues and probably of the amino-purine nucleotides as well.

Author(s):  
Lavinel G. IONESCU ◽  
Vera Lucia Trindade ◽  
Elizabeth Fatima de Souza

The experimental results obtained/or the hydrolysis of p-nitrophenyl diphenyl phosphate (NPDPP) in the presence of sodium hydroxide (NaOH), micelles of cetyltrimethylammonium bromide (CTAB), and an aqueous solution of glycerol were analyzed taking into consideration the internal pressure and the cohesive forces of the reaction medium. The effect of glycerol on mice/le formation and also its influence on the internal pressure of the reaction medium are large enough to affect the micellar catalyzed alkaline hydrolysis of the phosphate ester.


1987 ◽  
Vol 52 (11) ◽  
pp. 2792-2800 ◽  
Author(s):  
Ivan Rosenberg ◽  
Antonín Holý

Reaction of 9-(S)-(3-hydroxy-2-phosphonylmethoxypropyl)adenine (I) with N,N'-dicyclohexylcarbodiimide afforded the cyclic phosphonate II. The same compound was also obtained by controlled alkaline hydrolysis of 3'-O-chloromethanephosphonyl-9-(S)-(2,3-dihydroxypropyl)adenine (III). Methanolysis of compound II or III by sodium methoxide gave methyl ester VII. Isomeric cyclic ester V and methyl ester VIII were obtained from 3'-O-phosphonylmethyl ether IV or 2'-O-chloromethanephosphonyl ester VI by the same reactions. Compound I was transformed into morpholide IX which afforded the P-diphosphoryl derivative X by treatment with inorganic diphosphate. The P-phosphoryl derivative XII was obtained from compound I by successive protection with dimethoxytrityl chloride, activation with diphenyl chlorophosphate, treatment with inorganic phosphate and acid deprotection.


1962 ◽  
Vol 40 (8) ◽  
pp. 1626-1631 ◽  
Author(s):  
Louis-Marie Babineau ◽  
Louis Berlinguet

New N-ε-substituted lysines have been synthetized as follows: by condensing 5-δ-bromobutylhydantoin with different primary amines, 5-δ-alkylaminobutylhydantoins were obtained, the alkaline hydrolysis of which gave the corresponding N-ε-substituted lysines. N-α-Substituted hexahomoserines have also been prepared by acid hydrolysis of the reaction product between α,ε-dihydroxycaproic nitrile and primary amines. 5-Amino-5-carboxypentane sulphonamide has been prepared in the following way: 5-δ-bromobutylhydantoin was reacted with thiourea, and the resulting isothiouronium salt was oxidized with chlorine. Gaseous ammonia was then bubbled through an ethereal suspension of the 5-δ-chlorosulphonyl butylhydantoin and the resulting sulphonamide was hydrolyzed under pressure with barium hydroxide. 5-Amino-5-carboxypentane sulphonamide was then isolated and crystallized.


2016 ◽  
Vol 18 (27) ◽  
pp. 18255-18267 ◽  
Author(s):  
Eufrásia S. Pereira ◽  
Júlio C. S. Da Silva ◽  
Tiago A. S. Brandão ◽  
Willian R. Rocha

Ab initio molecular dynamics simulations revealed that phosphorane, an important intermediate in the hydrolysis of phosphate diesters, has a lifetime of ∼1 ps in aqueous solution. QTAIM and EDA analyses along the reaction coordinate show that the hydrolysis reaction of phosphate esters is driven mainly by electrostatic interactions.


2020 ◽  
Author(s):  
Klaudia Szeler ◽  
Nicholas Williams ◽  
Alvan C. Hengge ◽  
Shina Caroline Lynn Kamerlin

<div> <div> <div> <p>Phosphate and sulfate esters have important roles as biological building blocks and in regulating cellular processes. However, while there has been substantial experimental and computational investigation of the mechanisms and the transition states involved in phosphate ester hydrolysis, there is far less (in particular computational) work on sulfate ester hydrolysis. Here, we report a detailed computational study of the alkaline hydrolysis of diaryl sulfate diesters, using different DFT functionals and both pure implicit solvation as well as mixed implicit/explicit solvation with varying numbers of explicit water molecules. We consider both the impact of how the system is modeled on computed linear free energy relationships (LFER) and the nature of the transition states. Although our calculations consistently underestimate the absolute activation free energies, we obtain good agreement with experimental LFER data when using pure implicit solvent, and excellent agreement with experimental kinetic isotope effects for all models used. Our calculations suggest that the hydrolysis of sulfate diesters proceeds through loose transition states, with minimal bond formation to the nucleophile and with bond cleavage to the leaving group already initiated. Comparison to prior work indicates that these transition states are similar in nature to those of analogous reactions such as the alkaline hydrolysis of neutral arylsulfonate monoesters or charged phosphate diesters and fluorophosphates. Obtaining more detailed insight into the transition states involved assists in understanding the selectivity of enzymes that hydrolyze these reactions; however, this work also highlights the methodological challenges involved in reliably modeling sulfate ester hydrolysis. </p> </div> </div> </div>


1942 ◽  
Vol 20b (9) ◽  
pp. 185-188 ◽  
Author(s):  
B. S. Rabinovitch ◽  
C. A. Winkler

Some contradictory points recorded for the alkaline hydrolysis of nitriles have been clarified by a study of propionitrile hydrolysis in aqueous sodium hydroxide solutions of concentration 0.3 to 4 N. It has been shown that the rate of alkaline hydrolysis of propionitrile is given by the rate of formation of total ammonia and intermediate amide and not by that of ammonia alone. The relative rates of propionitrile and propionamide hydrolysis were found to be approximately 1:10 over the whole alkali concentration range. The bimolecular velocity constant is essentially independent of alkali concentration. An activation energy of 20,300 cal. was determined for the reaction in 0.65 N alkali.


1997 ◽  
Vol 75 (4) ◽  
pp. 441-448
Author(s):  
Khamis A. Abbas ◽  
Phillip Hurst ◽  
John T. Edward

The rates of hydrolysis in aqueous sodium hydroxide of the alkaloid strychnine and seven of its derivatives have been determined at 50 and 75 °C. The kinetic data indicate that all the compounds, except strychninesulfoni acid-I, hydrolyze by competing second- and third-order mechanisms, involving one and two hydroxide ions, respectively; strychninesulfonic acid-I hydrolyzes by the second-order mechanism only. The quantitative effect of positively charged groups in enhancing, and negatively charged groups in depressing, the rates of hydrolysis is in rough agreement with calculations using Kirkwood–Westheimer theory. Keywords: Kirkwood–Westheimer theory; strychnine derivatives, hydrolysis of; lactams, hydrolysis of; electrostatic effects on rates of alkaline hydrolysis; alkaloids, reactions of.


Author(s):  
Klaudia Szeler ◽  
Nicholas Williams ◽  
Alvan C. Hengge ◽  
Shina Caroline Lynn Kamerlin

<div> <div> <div> <p>Phosphate and sulfate esters have important roles as biological building blocks and in regulating cellular processes. However, while there has been substantial experimental and computational investigation of the mechanisms and the transition states involved in phosphate ester hydrolysis, there is far less (in particular computational) work on sulfate ester hydrolysis. Here, we report a detailed computational study of the alkaline hydrolysis of diaryl sulfate diesters, using different DFT functionals and both pure implicit solvation as well as mixed implicit/explicit solvation with varying numbers of explicit water molecules. We consider both the impact of how the system is modeled on computed linear free energy relationships (LFER) and the nature of the transition states. Although our calculations consistently underestimate the absolute activation free energies, we obtain good agreement with experimental LFER data when using pure implicit solvent, and excellent agreement with experimental kinetic isotope effects for all models used. Our calculations suggest that the hydrolysis of sulfate diesters proceeds through loose transition states, with minimal bond formation to the nucleophile and with bond cleavage to the leaving group already initiated. Comparison to prior work indicates that these transition states are similar in nature to those of analogous reactions such as the alkaline hydrolysis of neutral arylsulfonate monoesters or charged phosphate diesters and fluorophosphates. Obtaining more detailed insight into the transition states involved assists in understanding the selectivity of enzymes that hydrolyze these reactions; however, this work also highlights the methodological challenges involved in reliably modeling sulfate ester hydrolysis. </p> </div> </div> </div>


1974 ◽  
Vol 52 (5) ◽  
pp. 697-701 ◽  
Author(s):  
Wayne I. Congdon ◽  
John T. Edward

N-Benzoylthiourea (pKHA 10.9) and other N-acylthioureas ionize in alkaline solution, and then are rapidly hydrolyzed to thiourea and a carboxylic acid. The rates become independent of hydroxide ion concentration when this exceeds about 0.1 M and point to a mechanism in which hydrolysis takes place by attack of an hydroxide ion on the un-ionized molecule of N-acylthiourea. This mechanism accords with the Arrhenius parameters for the hydrolysis of N-benzoylthiourea in 0.2 N sodium hydroxide, and with the Hammett ρ value of 0.10 for the hydrolysis of m- and p-substituted N-benzoylthioureas in 1.0 N potassium hydroxide.


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