1612-65-3Relevant articles and documents
Structure and activity of NADPH-dependent reductase Q1EQE0 from streptomyces kanamyceticus, which catalyses the R-selective reduction of an imine substrate
Rodriguez-Mata, Maria,Frank, Annika,Wells, Elizabeth,Leipold, Friedemann,Turner, Nicholas J.,Hart, Sam,Turkenburg, Johan P.,Grogan, Gideon
, p. 1372 - 1379 (2013)
NADPH-dependent oxidoreductase Q1EQE0 from Streptomyces kanamyceticus catalyzes the asymmetric reduction of the prochiral monocyclic imine 2-methyl-1-pyrroline to the chiral amine (R)-2-methylpyrrolidine with >99% ee, and is thus of interest as a potential biocatalyst for the production of optically active amines. The structures of Q1EQE0 in native form, and in complex with the nicotinamide cofactor NADPH have been solved and refined to a resolution of 2.7 A. Q1EQE0 functions as a dimer in which the monomer consists of an N-terminal Rossman-fold motif attached to a helical C-terminal domain through a helix of 28 amino acids. The dimer is formed through reciprocal domain sharing in which the C-terminal domains are swapped, with a substrate-binding cleft formed between the N-terminal subunit of monomer A and the C-terminal subunit of monomer B. The structure is related to those of known β-hydroxyacid dehydrogenases, except that the essential lysine, which serves as an acid/base in the (de)protonation of the nascent alcohol in those enzymes, is replaced by an aspartate residue, Asp187 in Q1EQE0. Mutation of Asp187 to either asparagine or alanine resulted in an inactive enzyme.
Partial purification and substrate specificity of flavin-containing monooxygenase from rat brain microsomes
Kawaji,Miki,Takabatake
, p. 1657 - 1659 (1995)
Flavin-containing monooxygenase (FMO) was partially purified from rat brain microsomes through two successive chromatographies on columns of DEAE Sepharose and 2',5'-ADP Sepharose. The specific activity, benzydamine N- oxidation of partially purified brai
Coumarin[4]arene: A Fluorescent Macrocycle
Kumar, Pawan,Venkatakrishnan, Parthasarathy
, p. 1295 - 1299 (2018)
The pyranone functionalization of the upper rim of resorcinarene to provide the coumarin macrocycle called "coumarin[4]arene", possessing visible fluorescence and conformationally flexible behavior suitable for molecular recognition, has been successfully synthesized and characterized.
A novel linker strategy for solid-phase synthesis
Morphy, J. Richard,Rankovic, Zoran,Rees, David C.
, p. 3209 - 3212 (1996)
The REM resin for solid phase synthesis is described. Its use is illustrated by preparing a small array of tertiary amines using a Hoffman elimination reaction. No functional group is required for linking these compounds onto the resin other than the amin
Soluble polymer bound cleavage reagents: A multipolymer strategy for the cleavage of tertiary amines from REM resin
Toy, Patrick H.,Reger, Thomas S.,Janda, Kim D.
, p. 2205 - 2207 (2000)
(equation presented) Soluble polymer bound reagent 1 has been prepared to cleave tertiary amines from REM resin. Normally, amines cleaved from REM resin require extraction or chromatography to remove excess cleavage reagent and its byproducts. The solubility profile of non-crosslinked polystyrene (NCPS) based reagent 1 eliminates the need for such purification and allows for the direct isolation of a library of pure tertiary amines through simple filtration and concentration operations.
Towards the Development of Frustrated Lewis Pair (FLP) Catalyzed Hydrogenations of Tertiary and Secondary Carboxylic Amides
K?ring, Laura,Paradies, Jan,Sitte, Nikolai A.
supporting information, p. 1287 - 1300 (2022/01/20)
The development of the frustrated Lewis pair catalyzed hydrogenation of tertiary and secondary amides is reviewed. Detailed insight into our strategies in order to overcome challenges during the reaction development process is provided. Furthermore, the d
Metal-free reduction of unsaturated carbonyls, quinones, and pyridinium salts with tetrahydroxydiboron/water
Li, Tiejun,Peng, Henian,Tang, Wenjun,Tian, Duanshuai,Xu, Guangqing,Yang, He
, p. 4327 - 4337 (2021/05/31)
A series of unsaturated carbonyls, quinones, and pyridinium salts have been effectively reduced to the corresponding saturated carbonyls, dihydroxybenzenes, and hydropyridines in moderate to high yields with tetrahydroxydiboron/water as a mild, convenient, and metal-free reduction system. Deuterium-labeling experiments have revealed this protocol to be an exclusive transfer hydrogenation process from water. This journal is
Covalent Organic Frameworks toward Diverse Photocatalytic Aerobic Oxidations
Liu, Shuyang,Tian, Miao,Bu, Xiubin,Tian, Hua,Yang, Xiaobo
, p. 7738 - 7744 (2021/05/07)
Photoactive two-dimensional covalent organic frameworks (2D-COFs) have become promising heterogenous photocatalysts in visible-light-driven organic transformations. Herein, a visible-light-driven selective aerobic oxidation of various small organic molecules by using 2D-COFs as the photocatalyst was developed. In this protocol, due to the remarkable photocatalytic capability of hydrazone-based 2D-COF-1 on molecular oxygen activation, a wide range of amides, quinolones, heterocyclic compounds, and sulfoxides were obtained with high efficiency and excellent functional group tolerance under very mild reaction conditions. Furthermore, benefiting from the inherent advantage of heterogenous photocatalysis, prominent sustainability and easy photocatalyst recyclability, a drug molecule (modafinil) and an oxidized mustard gas simulant (2-chloroethyl ethyl sulfoxide) were selectively and easily obtained in scale-up reactions. Mechanistic investigations were conducted using radical quenching experiments and in situ ESR spectroscopy, all corroborating the proposed role of 2D-COF-1 in photocatalytic cycle.
Recyclable covalent triazine framework-supported iridium catalyst for the N-methylation of amines with methanol in the presence of carbonate
Liu, Peng,Yang, Jiazhi,Ai, Yao,Hao, Shushu,Chen, Xiaozhong,Li, Feng
, p. 281 - 290 (2021/03/26)
An iridium complex Cp*Ir@CTF, which is synthesized by the coordinative immobilization of [Cp*IrCl2]2 on a functionalized covalent triazine framework (CTF), was found to be a general and highly efficient catalyst for the N-methylation of amines with methanol in the presence of carbonate. Under environmentally benign conditions, a variety of desirable products were obtained in high yields with complete selectivities and functional group friendliness. Furthermore, the synthesized catalyst could be recycled by simple filtration without obvious loss of catalytic activity after sixth cycle. Notably, this research exhibited the potential of covalent triazine framework-supported transition metal catalysts for hydrogen autotransfer process.
N-Methylation of Amines with Methanol in the Presence of Carbonate Salt Catalyzed by a Metal-Ligand Bifunctional Ruthenium Catalyst [(p-cymene)Ru(2,2′-bpyO)(H2O)]
Liu, Peng,Tung, Nguyen Thanh,Xu, Xiangchao,Yang, Jiazhi,Li, Feng
, p. 2621 - 2631 (2021/02/27)
A ruthenium complex [(p-cymene)Ru(2,2′-bpyO)(H2O)] was found to be a general and efficient catalyst for the N-methylation of amines with methanol in the presence of carbonate salt. Moreover, a series of sensitive substituents, such as nitro, ester, cyano, and vinyl groups, were tolerated under present conditions. It was confirmed that OH units in the ligand are crucial for the catalytic activity. Notably, this research exhibited the potential of metal-ligand bifunctional ruthenium catalysts for the hydrogen autotransfer process.