5 publications

5 publications

Asymmetric Catalytic Sulfoxidation by a Novel VIV8 Cluster Catalyst in the Presence of Serum Albumin: A Simple and Green Oxidation System

Bian, H.-D.; Huang, F.-P.

RSC Adv. 2016, 6, 44154-44162, 10.1039/C6RA08153C

Enantioselective oxidation of a series of alkyl aryl sulfides catalyzed by a novel VIV8 cluster is tested in an aqueous medium in the presence of serum albumin. The procedure is simple, environmentally friendly, selective, and highly reactive.


Metal: V
Anchoring strategy: Undefined
Optimization: Chemical
Reaction: Sulfoxidation
Max TON: 140
ee: 77
PDB: ---
Notes: Screening with different serum albumins.

Enantioselective Sulfoxidation Mediated by Vanadium-Incorporated Phytase: A Hydrolase Acting as a Peroxidase

Sheldon, R.A.

Chem. Commun. 1998, 1891-1892, 10.1039/a804702b

Phytase (E.C. 3.1.3.8), which in vivo mediates the hydrolysis of phosphate esters, catalyses the enantioselective oxidation of thioanisole with H2O2, both in the presence and absence of vanadate ion, affording the S-sulfoxide in up to 66% ee at 100% conversion.


Metal: V
Ligand type: Undefined
Host protein: Phytase
Anchoring strategy: Undefined
Optimization: ---
Reaction: Sulfoxidation
Max TON: ~194
ee: 66
PDB: ---
Notes: ---

Metal: V
Ligand type: Oxide
Host protein: Phytase
Anchoring strategy: Undefined
Optimization: ---
Reaction: Sulfoxidation
Max TON: 550
ee: 66
PDB: ---
Notes: ---

Incorporation of Biotinylated Manganese-Salen Complexes into Streptavidin: New Artificial Metalloenzymes for Enantioselective Sulfoxidation

Ward, T.R.

J. Organomet. Chem. 2009, 694, 930-936, 10.1016/j.jorganchem.2008.11.023

Incorporation of achiral biotinylated manganese-salen complexes into streptavidin yields artificial metalloenzymes for aqueous sulfoxidation using hydrogen peroxide. Four biotinylated salen ligands were synthesized and their manganese complexes were tested in combination with several streptavidin mutants, yielding moderate conversions (up to 56%) and low enantioselectivities (maximum of 13% ee) for the sulfoxidation of thioanisole.


Metal: Mn
Ligand type: Oxide; Salen
Host protein: Streptavidin (Sav)
Anchoring strategy: Supramolecular
Optimization: Chemical & genetic
Reaction: Sulfoxidation
Max TON: 28
ee: 13
PDB: ---
Notes: ---

The Rational Design of Semisynthetic Peroxidases

Sheldon, R.A.

Biotechnol. Bioeng. 2000, 67, 87-96, 10.1002/(SICI)1097-0290(20000105)67:1<87::AID-BIT10>3.0.CO;2-8

A semisynthetic peroxidase was designed by exploiting the structural similarity of the active sites of vanadium dependent haloperoxidases and acid phosphatases. Incorporation of vanadate ion into the active site of phytase (E.C. 3.1.3.8), which mediates in vivo the hydrolysis of phosphate esters, leads to the formation of a semisynthetic peroxidase, which catalyzes the enantioselective oxidation of prochiral sulfides with H2O2 affording the S‐sulfoxide, e.g. in 66% ee at 100% conversion for thioanisole. Under reaction conditions the semi‐synthetic vanadium peroxidase is stable for over 3 days with only a slight decrease in turnover frequency. Polar water‐miscible cosolvents, such as methanol, dioxane, and dimethoxyethane, can be used in concentrations of 30% (v/v) at a small penalty in activity and enantioselectivity. Among the transition metal oxoanions that are known to be potent inhibitors, only vanadate resulted in a semisynthetic peroxidase when incorporated into phytase. A number of other acid phosphatases and hydrolases were tested for peroxidase activity, when incorporated with vanadate ion. Phytases from Aspergillus ficuum, A. fumigatus, and A. nidulans, sulfatase from Helix pomatia, and phospholipase D from cabbage catalyzed enantioselective oxygen transfer reactions when incorporated with vanadium. However, phytase from A. ficuum was unique in also catalyzing the enantioselective sulfoxidation, albeit at a lower rate, in the absence of vanadate ion.


Metal: V
Ligand type: Oxide
Host protein: Phytase
Anchoring strategy: Undefined
Optimization: Chemical
Reaction: Sulfoxidation
Max TON: ---
ee: 66
PDB: ---
Notes: Reaction performed in 30% organic co-solvent.

Vanadium-Catalysed Enantioselective Sulfoxidations: Rational Design of Biocatalytic and Biomimetic Systems

Sheldon, R.A.

Top. Catal. 2000, 13, 259-265, 10.1023/A:1009094619249

Approaches to the rational design of vanadium-based biocatalytic and biomimetic model systems as catalysts for enantioselective oxidations are reviewed. Incorporation of vanadate ion into the active site of phytase (E.C. 3.1.3.8), which in vivo mediates the hydrolysis of phosphate esters, afforded a relatively stable and inexpensive semi-synthetic peroxidase. It catalysed the enantioselective oxidation of prochiral sulfides with H2O2 affording the S-sulfoxide, e.g., in 68% ee at 100% conversion for thioanisole. Amongst the transition metal oxoanions that are known to be potent inhibitors of phosphatases, only vanadate resulted in a semi-synthetic peroxidase, when incorporated into phytase. In a biomimetic approach, vanadium complexes of chiral Schiff's base complexes were encapsulated in the super cages of a hydrophobic zeolite Y. Unfortunately, these ship-in-a-bottle complexes afforded only racemic sulfoxide in the catalytic oxidation of thioanisole with H2O2.


Metal: V
Ligand type: Oxide
Host protein: Phytase
Anchoring strategy: Undefined
Optimization: Chemical
Reaction: Sulfoxidation
Max TON: ---
ee: 68
PDB: ---
Notes: ---