The Experts below are selected from a list of 1122 Experts worldwide ranked by ideXlab platform
A V Stepakov - One of the best experts on this subject based on the ideXlab platform.
-
stereo and regioselective 1 3 dipolar cycloaddition of the stable ninhydrin derived Azomethine Ylide to cyclopropenes trapping of unstable cyclopropene dipolarophiles
Journal of Organic Chemistry, 2019Co-Authors: Alexander S Filatov, Anna G Larina, Vitali M Boitsov, A V Stepakov, Siqi Wang, Olesya V. Khoroshilova, Stanislav V. LozovskiyAbstract:A stereo- and regioselective 1,3-dipolar cycloaddition of the stable ninhydrin-derived Azomethine Ylide [2-(3,4-dihydro-2H-pyrrolium-1-yl)-1-oxo-1H-inden-3-olate, DHPO] to differently substituted c...
-
Stereo- and Regioselective 1,3-Dipolar Cycloaddition of the Stable Ninhydrin-Derived Azomethine Ylide to Cyclopropenes: Trapping of Unstable Cyclopropene Dipolarophiles
2019Co-Authors: Alexander S. Filatov, Anna G Larina, Vitali M Boitsov, Siqi Wang, Olesya V. Khoroshilova, Stanislav V. Lozovskiy, A V StepakovAbstract:A stereo- and regioselective 1,3-dipolar cycloaddition of the stable ninhydrin-derived Azomethine Ylide [2-(3,4-dihydro-2H-pyrrolium-1-yl)-1-oxo-1H-inden-3-olate, DHPO] to differently substituted cyclopropenes has been established. As a result, an efficient synthetic protocol was developed for the preparation of biologically relevant spiro[cyclopropa[a]pyrrolizine-2,2′-indene] derivatives. DHPO has proved to be an effective trap for such highly reactive and unstable substrates as parent cyclopropene, 1-methylcyclopropene, 1-phenylcyclopropene, and 1-halo-2-phenylcyclopropenes. It has also been found that 3-nitro-1,2-diphenylcyclopropene undergoes a nucleophilic substitution reaction in alcohols and thiols to afford 3-alkoxy- and 3-arylthio-substituted 1,2-diphenylcyclopropenes, which can be captured as corresponding 1,3-dipolar cycloadducts in the presence of DHPO. These new approaches provide a straightforward strategy for the synthesis of functionally substituted cyclopropa[a]pyrrolizine derivatives. The factors governing regio- and stereoselectivity have been revealed by means of quantum mechanical calculations (M11 density functional theory), including previously unreported NYlide–Hcyclopropene second-orbital interactions. The outcome of this work contributes to the study of 1,3-dipolar cycloaddition, as well as enriches chemistry of cyclopropenes and methods for the construction of polycyclic compounds with cyclopropane fragments
-
synthesis of functionalized 3 spiro cyclopropa a pyrrolizine and 3 spiro 3 azabicyclo 3 1 0 hexane oxindoles from cyclopropenes and Azomethine Ylides via 3 2 cycloaddition
Journal of Organic Chemistry, 2017Co-Authors: Alexander S Filatov, Nickolay A Knyazev, A P Molchanov, Taras L Panikorovsky, R R Kostikov, Anna G Larina, Vitali M Boitsov, A V StepakovAbstract:3-Spiro[cyclopropa[a]pyrrolizine]- and 3-spiro[3-azabicyclo[3.1.0]hexane]oxindoles were prepared in moderate to high yields via one-pot three-component reactions using substituted isatins, α-amino acids, and cyclopropenes. The key step is an intramolecular [3 + 2]-cycloaddition reaction of an in situ generated Azomethine Ylide onto a cyclopropene. Both N-substituted and N-unsubstituted α-amino acids, dipeptide Gly-Gly, and also benzylamine were used as the amine component for the Azomethine Ylide generation. The anticancer activity of some of the obtained compounds against human leukemia K562 cell line was evaluated by flow cytometry in vitro.
-
Synthesis of Functionalized 3‑Spiro[cyclopropa[a]pyrrolizine]- and 3‑Spiro[3-azabicyclo[3.1.0]hexane]oxindoles from Cyclopropenes and Azomethine Ylides via [3 + 2]-Cycloaddition
2016Co-Authors: Alexander S. Filatov, Nickolay A Knyazev, A P Molchanov, Taras L Panikorovsky, R R Kostikov, Anna G Larina, Vitali M Boitsov, A V StepakovAbstract:3-Spiro[cyclopropa[a]pyrrolizine]- and 3-spiro[3-azabicyclo[3.1.0]hexane]oxindoles were prepared in moderate to high yields via one-pot three-component reactions using substituted isatins, α-amino acids, and cyclopropenes. The key step is an intramolecular [3 + 2]-cycloaddition reaction of an in situ generated Azomethine Ylide onto a cyclopropene. Both N-substituted and N-unsubstituted α-amino acids, dipeptide Gly-Gly, and also benzylamine were used as the amine component for the Azomethine Ylide generation. The anticancer activity of some of the obtained compounds against human leukemia K562 cell line was evaluated by flow cytometry in vitro
Raghavachary Raghunathan - One of the best experts on this subject based on the ideXlab platform.
-
expeditious synthesis of bicyclic pyrrolidine pyrrolizidine thiazolidine grafted macrocycles through intramolecular 1 3 dipolar cycloaddition of Azomethine Ylides
ChemInform, 2014Co-Authors: S Purushothaman, R Prasanna, Raghavachary RaghunathanAbstract:Alkenyl aldehydes (I) react with secondary aminoacids to generate Azomethine Ylide intermediates, which undergo intramolecular 1,3-dipolar cycloaddition to give macrocyclic products.
-
synthesis of pyrrolo 2 3 a pyrrolizine and pyrrolizine 2 3 a pyrrolizine derived from allyl derivatives of baylis hillman adducts through intramolecular 1 3 dipolar cycloaddition
Tetrahedron Letters, 2009Co-Authors: Subban Kathiravan, Ekambaram Ramesh, Raghavachary RaghunathanAbstract:Abstract The synthesis of a series of pyrrole-based polycyclic heterocycles has been accomplished through an intramolecular 1,3-dipolar cycloaddition reaction of an Azomethine Ylide with the dipolarophile derived from Baylis–Hillman adducts. Improved yields of the products were obtained when the reaction was carried out under microwave conditions.
-
regioselective synthesis and antimicrobial screening of novel ketocarbazolodispiropyrrolidine derivatives
European Journal of Medicinal Chemistry, 2009Co-Authors: Govindasami Periyasami, Raghavachary Raghunathan, Gangadharan Surendiran, Narayanasamy MathivananAbstract:A series of novel dispiropyrrolidine derivatives have been synthesized through 1,3-dipolar cycloaddition reaction of Azomethine Ylide generated from sarcosin and di/tri ketone with the dipolarophile (E)-2-arylidine-1-keto-carbazoles. The cycloadducts ketocarbazalo spiro N-methyl pyrrolidines showed the most interesting antimicrobial activity at lower concentration.
-
synthesis of novel spiropyrrolizidines as potent antimicrobial agents for human and plant pathogens
Bioorganic & Medicinal Chemistry Letters, 2008Co-Authors: Govindasami Periyasami, Raghavachary Raghunathan, Gangadharan Surendiran, Narayanasamy MathivananAbstract:A series of novel dispirooxindolopyrrolizidine derivatives have been synthesized through 1,3-dipolar cycloaddition reaction of Azomethine Ylide generated from proline and isatin with the dipolarophile (E)-2-arylidine-1-keto carbazoles. The synthesized cycloadducts were evaluated for antimicrobial activities. Compounds 7d and 7e showed relatively good antibacterial and antifungal activities.
-
a greener approach for the synthesis of 1 n methyl spiro 2 3 oxindolespiro 3 2 spiro 2 3 indan 1 3 dionespiro 2 2 cyclopentanone 4 aryl pyrrolidines
Tetrahedron Letters, 2007Co-Authors: T Gunasundari, Gowri Sridhar, Raghavachary RaghunathanAbstract:Abstract N , N -Dimethylammonium N ′, N ′-dimethyl carbamate (DIMCARB), a reusable reaction medium, has been used in the synthesis of a number of monoarYlidene cyclopentanones. These compounds are used as dipolarophiles in the 1,3-dipolar cycloaddition reaction of an Azomethine Ylide, generated in situ by the decarboxylation method for the synthesis of spiropyrrolidines by the application of microwave methodology.
Hongchao Guo - One of the best experts on this subject based on the ideXlab platform.
-
tandem 3 2 cycloaddition 1 4 addition reaction of Azomethine Ylides and aza o quinone methides for asymmetric synthesis of imidazolidines
Organic Letters, 2017Co-Authors: Hao Jia, Honglei Liu, Zhenyan Guo, Jiaxing Huang, Hongchao GuoAbstract:An enantioselective synthesis of biologically important imidazolidines has been achieved via a tandem [3 + 2] cycloaddition/1,4-addition reaction of Azomethine Ylide and aza-o-quinone methides. With the use of this tool, various imidazolidine derivatives are obtained in good yields with excellent diastereoselectivities and enantioselectivities.
-
Tandem [3 + 2] Cycloaddition/1,4-Addition Reaction of Azomethine Ylides and Aza‑o‑quinone Methides for Asymmetric Synthesis of Imidazolidines
2017Co-Authors: Hao Jia, Honglei Liu, Zhenyan Guo, Jiaxing Huang, Hongchao GuoAbstract:An enantioselective synthesis of biologically important imidazolidines has been achieved via a tandem [3 + 2] cycloaddition/1,4-addition reaction of Azomethine Ylide and aza-o-quinone methides. With the use of this tool, various imidazolidine derivatives are obtained in good yields with excellent diastereoselectivities and enantioselectivities
Vladimir S Moshkin - One of the best experts on this subject based on the ideXlab platform.
-
3 cyanochromones in 3 2 cycloadditions with an Azomethine Ylide derived from sarcosine and formaldehyde a short synthesis of 1 benzopyrano 2 3 c 3 4 c dipyrrolidines
ChemInform, 2014Co-Authors: Vyacheslav Ya. Sosnovskikh, Mikhail Yu Kornev, Vladimir S MoshkinAbstract:3-Substituted chromones undergo [3 + 2] cycloaddition with an Azomethine Ylide to produce benzopyranopyrrolidine derivatives (IV, isolated as hydrochlorides) in a diastereoselective manner.
-
highly diastereoselective 1 3 dipolar cycloaddition of nonstabilized Azomethine Ylides to 3 nitro 2 trihalomethyl 2h chromenes synthesis of 1 benzopyrano 3 4 c pyrrolidines
ChemInform, 2014Co-Authors: Vladislav Yu. Korotaev, Vladimir S Moshkin, Alexey Yu. Barkov, Mikhail I Kodess, Evgeniya G Matochkina, Vyacheslav Ya. SosnovskikhAbstract:Reactions of 3-nitro-2-trifluoro(trichloro)methyl-2H-chromenes, including 2-unsubstituted derivatives, with N-alkyl-a-amino acids (sarcosine, proline) and paraformaldehyde proceed diastereoselectively to give 1-benzopyrano[3,4-c]pyrrolidines in good yields as a result of a 1,3-dipolar cycloaddition of the intermediate nonstabilized Azomethine Ylide at the D 3 -bond of the chromene system.
-
3 cyanochromones in 3 2 cycloadditions with an Azomethine Ylide derived from sarcosine and formaldehyde a short synthesis of 1 benzopyrano 2 3 c 3 4 c dipyrrolidines
Tetrahedron Letters, 2014Co-Authors: Vyacheslav Ya. Sosnovskikh, Mikhail Yu Kornev, Vladimir S MoshkinAbstract:Abstract Reactions of 3-cyanochromones with sarcosine and paraformaldehyde proceed diastereoselectively to give 1-benzopyrano[2,3- c ]pyrrolidines and tetrahydro-1 H -spiro[chromeno[2,3- c ]pyrrol-9,5′-oxazolidine]-9a-carbonitriles, depending on the reactant ratio, as a result of a 1,3-dipolar cycloaddition of the intermediate nonstabilized Azomethine Ylide at the double bond and carbonyl group of the chromone system. The latter undergoes demethylenation and recyclization into a novel hexahydrochromeno[2,3- c :3,4- c ′]dipyrrole tetracyclic system on heating with hydrochloric acid.
-
nucleophilic properties of a nonstabilized Azomethine Ylide derived from sarcosine and cyclohexanone a novel domino reaction leading to substituted 4 aryl 2 pyrrolidones
Tetrahedron Letters, 2012Co-Authors: Vladimir S Moshkin, Vyacheslav Ya. Sosnovskikh, Gerd Volker RoschenthalerAbstract:Abstract A nonstabilized asymmetric Azomethine Ylide derived from sarcosine and cyclohexanone reacts with 3-substituted coumarins and ethyl benzYlidene malonate to give 4-aryl-2-pyrrolidones in moderate yields, and the adducts of classical 1,3-dipolar cycloadditions as the minor products. The main reaction proceeds via a domino process, starting with 1,4-nucleophilic addition to the conjugated double bond, and represents the first example of the nucleophilic properties of a nonstabilized Azomethine Ylide.
Vyacheslav Ya. Sosnovskikh - One of the best experts on this subject based on the ideXlab platform.
-
3 cyanochromones in 3 2 cycloadditions with an Azomethine Ylide derived from sarcosine and formaldehyde a short synthesis of 1 benzopyrano 2 3 c 3 4 c dipyrrolidines
ChemInform, 2014Co-Authors: Vyacheslav Ya. Sosnovskikh, Mikhail Yu Kornev, Vladimir S MoshkinAbstract:3-Substituted chromones undergo [3 + 2] cycloaddition with an Azomethine Ylide to produce benzopyranopyrrolidine derivatives (IV, isolated as hydrochlorides) in a diastereoselective manner.
-
highly diastereoselective 1 3 dipolar cycloaddition of nonstabilized Azomethine Ylides to 3 nitro 2 trihalomethyl 2h chromenes synthesis of 1 benzopyrano 3 4 c pyrrolidines
ChemInform, 2014Co-Authors: Vladislav Yu. Korotaev, Vladimir S Moshkin, Alexey Yu. Barkov, Mikhail I Kodess, Evgeniya G Matochkina, Vyacheslav Ya. SosnovskikhAbstract:Reactions of 3-nitro-2-trifluoro(trichloro)methyl-2H-chromenes, including 2-unsubstituted derivatives, with N-alkyl-a-amino acids (sarcosine, proline) and paraformaldehyde proceed diastereoselectively to give 1-benzopyrano[3,4-c]pyrrolidines in good yields as a result of a 1,3-dipolar cycloaddition of the intermediate nonstabilized Azomethine Ylide at the D 3 -bond of the chromene system.
-
3 cyanochromones in 3 2 cycloadditions with an Azomethine Ylide derived from sarcosine and formaldehyde a short synthesis of 1 benzopyrano 2 3 c 3 4 c dipyrrolidines
Tetrahedron Letters, 2014Co-Authors: Vyacheslav Ya. Sosnovskikh, Mikhail Yu Kornev, Vladimir S MoshkinAbstract:Abstract Reactions of 3-cyanochromones with sarcosine and paraformaldehyde proceed diastereoselectively to give 1-benzopyrano[2,3- c ]pyrrolidines and tetrahydro-1 H -spiro[chromeno[2,3- c ]pyrrol-9,5′-oxazolidine]-9a-carbonitriles, depending on the reactant ratio, as a result of a 1,3-dipolar cycloaddition of the intermediate nonstabilized Azomethine Ylide at the double bond and carbonyl group of the chromone system. The latter undergoes demethylenation and recyclization into a novel hexahydrochromeno[2,3- c :3,4- c ′]dipyrrole tetracyclic system on heating with hydrochloric acid.
-
nucleophilic properties of a nonstabilized Azomethine Ylide derived from sarcosine and cyclohexanone a novel domino reaction leading to substituted 4 aryl 2 pyrrolidones
Tetrahedron Letters, 2012Co-Authors: Vladimir S Moshkin, Vyacheslav Ya. Sosnovskikh, Gerd Volker RoschenthalerAbstract:Abstract A nonstabilized asymmetric Azomethine Ylide derived from sarcosine and cyclohexanone reacts with 3-substituted coumarins and ethyl benzYlidene malonate to give 4-aryl-2-pyrrolidones in moderate yields, and the adducts of classical 1,3-dipolar cycloadditions as the minor products. The main reaction proceeds via a domino process, starting with 1,4-nucleophilic addition to the conjugated double bond, and represents the first example of the nucleophilic properties of a nonstabilized Azomethine Ylide.
-
Nucleophilic properties of a nonstabilized Azomethine Ylide derived from sarcosine and cyclohexanone. A novel domino reaction leading to substituted 4-aryl-2-pyrrolidones
'Elsevier BV', 2012Co-Authors: Moshkin, Vladimir S., Vyacheslav Ya. Sosnovskikh, Röschenthaler, Gerd VolkerAbstract:A nonstabilized asymmetric Azomethine Ylide derived from sarcosine and cyclohexanone reacts with 3-substituted coumarins and ethyl benzYlidene malonate to give 4-aryl-2-pyrrolidones in moderate yields, and the adducts of classical 1,3-dipolar cycloadditions as the minor products. The main reaction proceeds via a domino process, starting with 1,4-nucleophilic addition to the conjugated double bond, and represents the first example of the nucleophilic properties of a nonstabilized Azomethine Ylide. © 2012 Published by Elsevier Ltd