851885-30-8Relevant articles and documents
Novel non-metal catalyst for catalyzing asymmetric hydrogenation of ketone and alpha, beta-unsaturated ketone
-
Paragraph 0138-0143, (2021/04/26)
The invention discloses a novel non-metal catalyst for catalyzing asymmetric hydrogenation of ketone and alpha, beta-unsaturated ketone. The preparation method of a chiral alcohol compound shown as formula IV comprises the following step of: reacting a ketone compound shown as formula V with hydrogen under the catalysis of tri(4-hydrotetrafluorophenyl)boron and a chiral oxazoline compound to obtain the chiral alcohol compound shown as the formula IV; the preparation method of a chiral tetralone compound shown as formula VI comprises the following step of: under the catalysis of tri(4-hydrotetrafluorophenyl)boron and a chiral oxazoline compound, reacting an alpha, beta-unsaturated ketone compound shown as formula VII with hydrogen to obtain the chiral tetralone compound shown as the formula VI. The method has the advantages of easy synthesis of raw materials, mild reaction conditions, simple operation, high stereoselectivity and the like, the ee value of the product is up to 92%, and the yield is up to 99%.
Asymmetric Hydrogenation of Ketones and Enones with Chiral Lewis Base Derived Frustrated Lewis Pairs
Du, Haifeng,Feng, Xiangqing,Gao, Bochao,Meng, Wei
supporting information, p. 4498 - 4504 (2020/02/05)
The concept of frustrated Lewis pairs (FLPs) has been widely applied in various research areas, and metal-free hydrogenation undoubtedly belongs to the most significant and successful ones. In the past decade, great efforts have been devoted to the synthesis of chiral boron Lewis acids. In a sharp contrast, chiral Lewis base derived FLPs have rarely been disclosed for the asymmetric hydrogenation. In this work, a novel type of chiral FLP was developed by simple combination of chiral oxazoline Lewis bases with achiral boron Lewis acids, thus providing a promising new direction for the development of chiral FLPs in the future. These chiral FLPs proved to be highly effective for the asymmetric hydrogenation of ketones, enones, and chromones, giving the corresponding products in high yields with up to 95 % ee. Mechanistic studies suggest that the hydrogen transfer to simple ketones likely proceeds in a concerted manner.
Expanding the Substrate Specificity of Thermoanaerobacter pseudoethanolicus Secondary Alcohol Dehydrogenase by a Dual Site Mutation
Musa, Musa M.,Bsharat, Odey,Karume, Ibrahim,Vieille, Claire,Takahashi, Masateru,Hamdan, Samir M.
, p. 798 - 805 (2018/02/21)
Here, we report the asymmetric reduction of selected phenyl-ring-containing ketones by various single- and dual-site mutants of Thermoanaerobacter pseudoethanolicus secondary alcohol dehydrogenase (TeSADH). The further expansion of the size of the substrate binding pocket in the mutant W110A/I86A not only allowed the accommodation of substrates of the single mutants W110A and I86A within the expanded active site but also expanded the substrate range of the enzyme to ketones bearing two sterically demanding groups (bulky–bulky ketones), which are not substrates for the TeSADH single mutants. We also report the regio- and enantioselective reduction of diketones with W110A/I86A TeSADH and single TeSADH mutants. The double mutant exhibited dual stereopreference to generate the Prelog products most of the time and the anti-Prelog products in a few cases.
Straightforward synthesis of enantiopure 2,3-dihydrobenzofurans by a sequential stereoselective biotransformation and chemical intramolecular cyclization
Mangas-Sanchez, Juan,Busto, Eduardo,Gotor-Fernandez, Vicente,Gotor, Vicente
supporting information; experimental part, p. 3498 - 3501 (2010/10/20)
(Equation Presented). A new family of optically active 2,3- dihydrobenzofurans has been prepared by a simple chemoenzymatic asymmetric strategy. This synthetic approach is based on the combination of a lipase-mediated kinetic resolution of 1-aryl-2-propanols or bioreduction of the corresponding ketones followed by an intramolecular cyclization reaction. These novel compounds have been prepared in enantiopure form and in good overall yield through a straightforward route.
NOVEL TYROSINE KINASE INHIBITORS
-
Page/Page column 68, (2009/10/22)
Provided are compounds of the formula (I): or a stereoisomer, tautomer, salt, hydrate or prodrug thereof that modulate tyrosine kinase activity, compositions comprising the compounds and methods of their use.
PYRIDINE CARBOXYLIC ACID DERIVATIVES AS GLUCOKINASE MODULATORS
-
Page/Page column 34, (2010/02/11)
A compound of Formula (I): wherein: A is phenyl or a 5- or 6-membered heteroaryl ring, optionally substituted; R1 and R2 are selected from hydrogen and methyl; with the proviso that at least one of R1 and R2 is