A simple DNase model system comprising a dinuclear Zn(II) complex in methanol accelerates the cleavage of a series of methyl aryl phosphate diesters by 10(11)-10(13).

  title={A simple DNase model system comprising a dinuclear Zn(II) complex in methanol accelerates the cleavage of a series of methyl aryl phosphate diesters by 10(11)-10(13).},
  author={A. A. Neverov and C. Liu and Shannon E Bunn and D. Edwards and Christopher J. White and Stephanie A. Melnychuk and R. Brown},
  journal={Journal of the American Chemical Society},
  volume={130 20},
The di-Zn(II) complex of 1,3-bis[ N1, N1'-(1,5,9-triazacyclododecyl)]propane with an associated methoxide ( 3:Zn(II) 2: (-)OCH 3) was prepared and its catalysis of the methanolysis of a series of fourteen methyl aryl phosphate diesters ( 6) was studied at s (s)pH 9.8 in methanol at 25.0 +/- 0.1 degrees C. Plots of k obs vs [ 3:Zn(II) 2: (-)OCH 3] free for all members of 6 show saturation behavior from which K(M) and kcat (max) were determined. The second order rate constants for the catalyzed… Expand
Solvent induced cooperativity of Zn(II) complexes cleaving a phosphate diester RNA analog in methanol.
The observations support an effect of the reduced polarity solvent that encourages the cooperative association of phosphate and two independent mononuclear complexes to give a reactive entity. Expand
On the question of stepwise vs. concerted cleavage of RNA models promoted by a synthetic dinuclear Zn(II) complex in methanol: implementation of a noncleavable phosphonate probe.
The rates of methanolysis of a series of O-aryl phenylphosphonates in the presence of increasing Zn(II) complex were analyzed to provide binding constants, Kb, and the catalytic rate constant, kcat(max), for the unimolecular decomposition of the 8:4 Michaelis complex, providing additional evidence consistent with a concerted cyclization of RNA models 1a-k. Expand
DFT computational study of the methanolytic cleavage of DNA and RNA phosphodiester models promoted by the dinuclear Zn(II) complex of 1,3-bis(1,5,9-triazacyclododec-1-yl)propane.
A density functional theory study of the cleavage of a DNA model and two RNA models promoted by the dinuclear Zn((II)) complex of 1,3-bis(1,5,9-triazacyclodododec-1-yl)propane formulated with a bridging methoxide was undertaken to determine possible mechanisms for the transesterification processes that are consistent with experimental data. Expand
Cleavage of models for RNA mediated by a diZn(II) complex of bis[1,4-N1,N1′(1,5,9-triazacyclododecanyl)]butane in methanol and ethanol
The cleavage of seven RNA model 2-hydroxypropyl aryl phosphates (1) catalyzed by a dinuclear Zn(II) complex of bis[1,4-N1,N1′(1,5,9-triazacyclododecanyl)]butane (4) was studied in methanol andExpand
Steric effects on the catalytic activities of zinc(II) complexes containing [12]aneN3 ligating units in the cleavage of the RNA and DNA model phosphates.
The work has further confirmed that the combination of the cooperativity between two metal ions and a medium effect could result in excellent catalytic activities for the cleavage of phosphate diesters. Expand
Combining medium effects and cofactor catalysis: metal-coordinated synzymes accelerate phosphate transfer by 10(8).
Catalysis by Zn(II)-CD6 is specifically inhibited by inorganic phosphate, allowing turnover regulation by product inhibition, which render synzyme Zn (II-CD6) an efficient enzyme model that reflects enzyme-like properties in a wide range of features. Expand
Comparison of Cu(II)-promoted leaving group stabilization of the cleavage of a homologous set of phosphate mono-, di-, and triesters in water, methanol, and ethanol.
The cleavage of a set of phosphate mono-, di-, and triesters having a Cu(II)-complexed 2-phenanthrolyl group at the ortho-position of a departing phenoxide was studied in water and ethanol.Expand
Cu(II)-promoted methanolysis of N,N-bis(2-picolyl)carbamates: rate-limiting metal ion delivery of coordinated alcoholate nucleophile followed by fast partitioning of a tetrahedral intermediate.
The common mechanism involves rate-limiting delivery of a Cu(II)-coordinated methoxide to the C═O unit to form a tetrahedral intermediate followed by fast partitioning to products by two pathways with relative barriers dependent on the (s)(s)pK(a)(HOAr/HOR). Expand
Leaving group assistance in the La3+-catalyzed cleavage of dimethyl (o-methoxycarbonyl)aryl phosphate triesters in methanol.
Two main observations are that the o-CO2Me group preferentially accelerates the cleavage of the phosphate triesters with poor leaving groupsrelative to those with good leaving groups and it provides an increase in cleavage rate relative to those of comparable substrates that do not have that functional group. Expand
Palladacycle-promoted solvolytic cleavage of O,O-dimethyl O-aryl phosphorothioates. Converting a phosphorane-like transition state to an observable intermediate.
Kinetic experiments indicate that the reaction of 5 with 6e, having a 4-chlorophenoxy leaving group, rapidly produces a transient intermediate, postulated to be the palladacycle-bound 5-coordinate thiophosphorane (7e) that exists long enough to obtain its UV/vis spectrum by stopped-flow spectrophotometry. Expand


Metal-catalyzed alcoholysis reactions of carboxylate and organophosphorus esters
Publisher Summary This chapter elaborates the metal ion-catalyzed hydrolytic reactions of esters, amides, and organophosphorus esters. Apart from being fundamentally interesting and industriallyExpand