28227-62-5

Upstream product

• 104-95-0 (4-bromophenyl)thioanisole 
• 934-71-4 1-bromo-4-(methylsulfinyl)benzene 
• 164021-74-3 (1S,2R)-(-)-2-[N-(3’,5’-di-tert-butylsalicylidene)amino]-1,2-diphenylethanol 
• 55962-05-5 [N-(p-tolylsulfonyl)imino]phenyliodinane 

Relevant academic research and scientific papers

Chiral Ligands in Hypervalent Iodine Compounds: Synthesis and Structures of Binaphthyl-Based λ3-Iodanes

Several novel binaphthyl-based chiral hypervalent iodine(III) reagents have been prepared and structurally analysed. Various asymmetric oxidative reactions were applied to evaluate the reactivities and stereoselectivities of those reagents. Moderate to excellent yields were observed; however, very low stereoselectivities were obtained. NMR experiments indicated that these reagents are very easily hydrolysed in either chloroform or DMSO solvents leading to the limited stereoselectivities. It is concluded that the use of chiral ligands is an unsuccessful way to prepare efficient stereoselective iodine(III) reagents.

Two enantiocomplementary Baeyer-Villiger monooxygenases newly identified for asymmetric oxyfunctionalization of thioether

Two enantiocomplementary Baeyer-Villiger monooxygenases RaBVMO and AmBVMO were identified by genome mining for the asymmetric sulfoxidation. Both recombinant BVMOs have optimal pH of 9.0 and temperature of 35 °C. The half-lives of RaBVMO and AmBVMO at 30 °C were 24.4 and 24.6 h. RaBVMO and AmBVMO exhibited broad substrate spectrum and could catalyze the oxidization of various compounds including fatty ketones, cyclic ketones, and thioethers. Kinetic parameters analysis revealed that both RaBVMO and AmBVMO displayed higher catalytic efficiency toward thioanisole than cyclohexanone. As much as 50 mM thioanisole could be completely oxidized by AmBVMO and RaBVMO with 99% (R) and 95% (S), respectively. Molecular docking analysis further provides evidence for the complementary enantioselectivity of RaBVMO and AmBVMO. Our results demonstrate the potential application of the two novel BVMOs in asymmetric synthesis of sulfoxides.

The Stereoselective Oxidation of para-Substituted Benzenes by a Cytochrome P450 Biocatalyst

The serine 244 to aspartate (S244D) variant of the cytochrome P450 enzyme CYP199A4 was used to expand its substrate range beyond benzoic acids. Substrates, in which the carboxylate group of the benzoic acid moiety is replaced were oxidised with high activity by the S244D mutant (product formation rates >60 nmol.(nmol-CYP)?1.min?1) and with total turnover numbers of up to 20,000. Ethyl α-hydroxylation was more rapid than methyl oxidation, styrene epoxidation and S-oxidation. The S244D mutant catalysed the ethyl hydroxylation, epoxidation and sulfoxidation reactions with an excess of one stereoisomer (in some instances up to >98 %). The crystal structure of 4-methoxybenzoic acid-bound CYP199A4 S244D showed that the active site architecture and the substrate orientation were similar to that of the WT enzyme. Overall, this work demonstrates that CYP199A4 can catalyse the stereoselective hydroxylation, epoxidation or sulfoxidation of substituted benzene substrates under mild conditions resulting in more sustainable transformations using this heme monooxygenase enzyme.

Ionic liquid-functionalized amphiphilic Janus nanosheets afford highly accessible interface for asymmetric catalysis in water

High oil/water interfacial area together with accessible interfaces for regents is the key to achieving efficient asymmetric catalysis in water. Herein, by taking advantage of the excellent interfacial activity of Janus nanosheets (JNS), as well as the unique compatibility of imidazolium ionic liquid (IL), we developed a series of IL-functionalized amphiphilic Janus mesosilica nanosheets which afford highly accessible reaction interfaces for highly enantioselective sulfoxidation in water. The JNS-typed chiral salen TiIV catalysts were prepared by selectively decorating hydrophobic chiral salen TiIV complex on one side of Janus mesosilica nanosheets through the imidazolium-based IL linker. Benefiting from the two-dimensional porous Janus structure, as well as the compatible IL linker, the IL-tagged JNS catalysts afforded high oil/water interfacial areas and highly accessible reaction interface for sulfides and H2O2, significantly accelerating asymmetric sulfoxidation in water using H2O2 as an oxidant. In addition, they can be facilely recovered for stable reuse by simple centrifugation.

Accessing Enantiopure Epoxides and Sulfoxides: Related Flavin-Dependent Monooxygenases Provide Reversed Enantioselectivity

Enantiopure organic compounds are of major importance for the chemical and pharmaceutical industry. Flavin-dependent group E monooxygenases, composed of monooxygenase and reductase, are known to perform epoxidation of substituted alkenes as well as sulfoxidation in a regio- and enantioselective fashion. Group E is divided into styrene monooxygenases (SMO) and indole monooxygenases (IMO). Hitherto mainly SMOs have been characterized. In this study, we assayed 31 monooxygenases from both types, while 23 of which showed activity. They almost exclusively produced (S)-styrene oxide at high enantiomeric excess with maximum activities of 0.73 μmol min?1 mg?1 (kcat=0.54 s?1). In case of sulfoxidation, we found that the enantioselectivity is contrary between both types. IMOs preferably produce the (S)-enantiomer while SMOs have a tendency to produce the (R)-enantiomer. Sequence analysis and molecular docking of substrates allowed identifying fingerprint motives: SMO N46-V48-H50-Y73-H76-S96 and IMO S46-Q48-M50-V/I73-I76-A96. These form an essential part of the active site while the loop (AS44-51) interacts with the co-substrate and other amino acids direct the substrate. The motives clearly distinguish group E monooxygenases and define the enantioselectivity and thus direct biotechnological applications. Two-hour biotransformations with several sulfides in conjunction with upscale experiments (10 and 100 mg scale) resulted in the identification of promising candidates for the realization of biocatalytic processes.

Light-controlled cooperative catalysis of asymmetric sulfoxidation based on azobenzene-bridged chiral salen TiIVcatalysts

Incorporation of azobenzene into the linker of bimetallic chiral salen TiIVcatalysts allowed the photoswitchable arrangement of the two Ti(salen) units throughcis/transphotoisomerization of azobenzene. The differently arranged Ti(salen) units changed their cooperative function to reflect the positional relationships, as a result, their efficiency as cooperative catalysts in asymmetric sulfoxidation could be readily controlled by light stimuli.

Asymmetric oxidation of sulfides catalyzed by (R)-6,6'-dibromo-BINOL derived titanium complex

An efficient asymmetric oxidation of sulfides was achieved using (R)-6,6'-dibromo-BINOL as chiral ligand in combination with Ti(OiPr)4 using 70% aqueous tertiary butyl hydroperoxide as oxidant. The resulting sulfoxides had high enantiopurities and good yields. A range of aryl alkyl and aryl benzyl sulfides were oxidized to the corresponding sulfoxides with 78–95% ee in 72–80% yields.

5-PHENYLAZAINDOLE DERIVATIVE HAVING AMPK ACTIVATING EFFECT

Provided is a compound which is useful as an AMPK activator. A compound represented by formula: wherein X is substituted or unsubstituted monocyclic heterocyclyl or the like; ring A is substituted aryl, substituted heteroaryl, substituted cycloalkyl, substituted cycloalkenyl, or substituted heterocyclyl, wherein the ring A may further have a substituent(s) other than Y; Y is halogen, hydroxy, cyano, nitro, carboxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl or the like; R4, R5, R6 and R7 are each independently hydrogen, halogen, hydroxy, cyano, nitro, carboxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted alkyloxy, substituted or unsubstituted alkylthio, substituted or unsubstituted alkylsulfonyl, substituted or unsubstituted acyl, substituted or unsubstituted carbamoyl, substituted or unsubstituted sulfamoyl, or substituted or unsubstituted amino; R8 is hydrogen, halogen, hydroxy, cyano, nitro, carboxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl or the like; and R9 is hydrogen, halogen, hydroxy, cyano, nitro, carboxy, substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl or the like, or its pharmaceutically acceptable salt.

An ionic liquid-functionalized amphiphilic Janus material as a Pickering interfacial catalyst for asymmetric sulfoxidation in water

Ionic liquid-functionalized amphiphilic Janus chiral salen TiIV catalysts were prepared by partial hydrophobic modification of silica with a chiral salen TiIV complex through an imidazolium ionic liquid (IL) linker. By optimizing their hydrophobic/hydrophilic balance, the IL-functionalized JNP materials exhibited excellent interfacial activity, significantly accelerating asymmetric sulfoxidation in water through the formation of stable Pickering emulsions. Moreover, catalyst recovery was readily achieved using centrifugation.

Enzymatic kinetic resolution of chiral sulfoxides-an enantiocomplementary approach

A new enzymatic assay for the preparation of chiral sulfoxides that is enantiocomplementary to the known (S)-enantiomer-reducing activity of methionine sulfoxide reductase A (MsrA) is described. To this end, we have utilized the enzyme DMSO reductase (DmsABC), recently discovered by us being highly upregulated in stationary phase E. coli bacteria.