نتایج جستجو برای: unsaturated compounds

تعداد نتایج: 241045  

Journal: :Angewandte Chemie 2011
Jian-Hua Xie Xiao-Yan Liu Jian-Bo Xie Li-Xin Wang Qi-Lin Zhou

The production of enantiopure chiral compounds is important for pharmaceutical and agrochemical industries because enantiomers can exhibit distinct biological activities. Therefore, processes that directly produce the desired enantiomer are desirable. First reported by Knowles, Horner et al. in 1968, catalytic asymmetric hydrogenation of unsaturated compounds such as olefins, ketones, and imine...

2013
Ashok P. Acharya Rahul D. Kamble Snehalkumar D. Patil Shrikant V. Hese Bhaskar S. Dawane

In present communication a novel series of benzodiazepine derivatives were synthesized from α, β-unsaturated ketones and evaluated for their antimicrobial activities. The α, β-unsaturated ketones were prepared by ClaisenSchimidt Condensation of Indan-1-one with different aldehydes in presence bleaching earth clay and PEG400 as Greener reaction solvent. A novel benzodiazepine derivatives were sy...

Journal: :Journal of lipid research 1970
B S Goodrich

The presence of a strong contact component in the sex and ovipositing behavior of the sheep blowfly Lucilia cuprina Wied. prompted an investigation into the chemical composition of the cuticular wax of the adult male and female flies as well as that of the blowfly puparia. Thin-layer chromatography indicated that the lipids in all the waxes examined comprise hydrocarbons, nonglyceryl esters, tr...

2018
Aitor Urosa Ignacio E Tobal Ángela P de la Granja M Carmen Capitán R F Moro Isidro S Marcos Narciso M Garrido Francisca Sanz Emilio Calle David Díez

A novel approach to the production of chiral 1,3-cyclohexadienals has been developed. The organocatalysed asymmetric reaction of different β-disubstituted-α,β-unsaturated aldehydes with a chiral α,β-unsaturated aldehyde in the presence of a Jørgensen-Hayashi organocatalyst provides easy and stereocontrolled access to the cyclohexadienal backbone. This method allows for the synthesis of potentia...

Journal: :Organic & biomolecular chemistry 2014
Rameshwar Prasad Pandit Yong Rok Lee

Sequential Wolff rearrangement of α-diazo-β-ketoesters followed by trapping of the ketene intermediates with enol ethers generated a variety of γ,δ-unsaturated β-ketoesters. This method involves a novel thermal cascade reaction and allows the synthesis of γ,δ-unsaturated β-ketoesters with trans-stereochemistry under catalyst-free conditions. The synthesized compounds were further transformed in...

2007
Jesús Marcos Segura

This contribution summarizes methods to compare bonded stationary phases for the compound-class HPLC separations of unsaturated polycyclic hydrocarbons and polar compounds. These strategies are based on the physical chemistry behavior of the functional group of the bonded stationary phase, behavior of the unsaturated polycyclic hydrocarbons under isocratic and gradient elution, regression analy...

Michael addition of pyrimidine and purine nucleobases to substituted as well as unsubstituted α,β-unsaturated esters efficiently proceeds in the presence of catalytic amount of zinc oxide in ionic liquid 1-butyl-3-methylimidazolium bromide (ZnO/[bmim]Br) under microwave irradiation to afford carboacyclic nucleosides, as biologically important compounds, in good to excellent yields and in short ...

2012
Urmila Berar

Chalcones are a class of α,β-unsaturated carbonyl compounds that form the central core for a variety of naturally occurring biologically active compounds. They exhibit tremendous potential to act as a pharmacological agent. Besides their various pharmacological activities, chalcones have been explored for different optical applications including second harmonic generation materials in non-linea...

Journal: :Organic & biomolecular chemistry 2016
Shuai-Shuai Li Wei-Huan Li Guo-Tai Zhang Ying-Qi Xia Chen-Fei Liu Fu Su Xiao-Mei Zhang Lin Dong

A novel one-pot synthesis of π-conjugated polycyclic compounds, which could undergo further facile transformation to form complex polycyclic heteroarene compounds, has been realized between 7-azaindoles and α,β-unsaturated ketones. This distinctive cascade process proceeds via a rhodium(iii)-catalyzed alkylation/copper-catalyzed radical annulation-aromatization pathway.

Journal: :Journal of the American Chemical Society 2011
Tianning Diao Shannon S Stahl

α,β-Unsaturated carbonyl compounds are versatile intermediates in the synthesis of pharmaceuticals and biologically active compounds. Here, we report the discovery and application of Pd(DMSO)(2)(TFA)(2) as a catalyst for direct dehydrogenation of cyclohexanones and other cyclic ketones to the corresponding enones, using O(2) as the oxidant. The substrate scope includes heterocyclic ketones and ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید