Results 101 to 110 of about 54,719 (255)

Hydroxylated Pyrrolidines. Enantiospecific Synthesis of all-cis 2,3,4,5-Substituted Pyrrolidine Derivatives from Serine

The Journal of Organic Chemistry, 2002
We report the enantiospecific synthesis of the sterically congested all-cis 2,3,4,5-substituted pyrrolidines 4, 5, and 6, from either D- or L-serine. Hemiaminal intermediate 13 is converted to the fully substituted pyrrolidine 15 by way of a tandem Wittig-Michael reaction.
Verma, S.K., Atanes, M.N., Busto, J.H., Thai, D.L., Rapoport, H.   +4 more
openaire   +4 more sources

Metal-mediated intramolecular hydroamination and hydro(acy)alkoxylation reactions [PDF]

, 2012
This PhD thesis describes work undertaken to effect asymmetric catalysis in hydroamination and hydro(acy)alkoxylation reactions of allenes. The introductory Chapter provides an overview of recent advances in asymmetric heterofunctionalisation reactions ...
Arbour, Jannine Louise, Arbour, Jannine Louise   +1 more
core   +1 more source

Strain Release of 1‐Azabicyclo[1.1.0]butanes as a Gateway to Highly Functionalized Azetidines: New Strategies and Structural Motifs

Chemistry – A European Journal, EarlyView.
Over the past decade, the interest in azetidines has continuously risen, by virtue of their highly appealing pharmaceutical properties. Monocyclic, spirocyclic, and bridged azetidines can be accessed by leveraging 1‐azabicyclo[1.1.0]butanes as precursors.
Yuri Gelato, Philipp Natho, Marco Colella, Renzo Luisi   +3 more
wiley   +1 more source

A New and Efficient Method for the Synthesis of 3,4-Disubstituted Pyrrolidine-2,5-diones

Molecules, 2012
A newly found reaction for the synthesis of 3,4-disubstituted 1-hydroxy-pyrrolidine-2,5-diones from 3-substituted coumarins and nitromethane has been elaborated. The reaction involved a simple and convenient experimental procedure.
Rositca D. Nikolova, Nevena I. Petkova, Eleonora D. Ilieva   +2 more
doaj   +1 more source

(E)-3-Heteroarylidenechroman-4-ones as potent and selective monoamine oxidase-B inhibitors [PDF]

, 2016
A series of (E)-3-heteroarylidenechroman-4-ones (1a-r) was designed, synthesized and investigated in vitro for their ability to inhibit the enzymatic activity of both human monoamine oxidase (hMAO) isoforms, hMAO-A and hMAO-B.
Alcaro, Stefano, BIAVA, Mariangela, DESIDERI, Nicoletta, FIORAVANTI, Rossella, Ortuso, Francesco, PROIETTI MONACO, LUCA, Yáñez, Matilde   +6 more
core   +1 more source

Identification and Characterization of the Designer Opioid N‐Pyrrolidino Fluetonitazene in Nasal Spray

Drug Testing and Analysis, EarlyView.
N‐Pyrrolidino fluetonitazene, a synthetic opioid, was identified and characterized in a nasal spray using GC‐MS, LC‐QTOF‐MS, NMR and FT‐IR. ABSTRACT Detection of drugs in non‐biological samples serves as a fundamental basis for identifying emerging trends in the field of new psychoactive substances and provides valuable information for optimizing ...
Fabian Picht, Valentin Cepus, Rona Hohlfeld, Julian Klingbeil, Marco Weber   +4 more
wiley   +1 more source

Crystal structure of ethyl (2S,2′R)-1′-benzyl-3-oxo-3H-dispiro[1-benzothiophene-2,3′-pyrrolidine-2′,11′′-indeno[1,2-b]quinoxaline]-4′-carboxylate

Acta Crystallographica Section E: Crystallographic Communications, 2015
In the title compound, C35H27N3O3S, the spiro-linked five-membered rings both adopt twisted conformations. The pyrrolidine ring makes dihedral angles of 80.5 (1) and 77.4 (9)° with the benzothiophene ring system and the quinoxaline ring system ...
J. Govindaraj, R. Raja, M. Suresh, R. Raghunathan, A. SubbiahPandi   +4 more
doaj   +1 more source

Asymmetric synthesis of 2-substituted oxetan-3-ones via metalated SAMP/RAMP hydrazones [PDF]

, 2013
2-Substituted oxetan-3-ones can be prepared in good yields and enantioselectivities (up to 84% ee) by the metalation of the SAMP/RAMP hydrazones of oxetan-3-one, followed by reaction with a range of electrophiles that include alkyl, allyl, and benzyl ...
Beasley, Benjamin, Clarkson, Guy J., Geden, Joanna V., Shipman, Michael   +3 more
core   +1 more source

On the Planarity of Heterocyclic Bay‐Substituted Perylenediimides: Insight into the Fluorescent Photoinduced Electron Transfer Sensing Framework

European Journal of Organic Chemistry, EarlyView.
Near‐infrared fluorescent pH indicators based on perylenediimide were constructed in a modular receptor–spacer–fluorophore–spacer–receptor format with heterocyclic amino moieties at the bay positions. Counterintuitively, the dibrominated intermediate with two heavy atoms is more emissive than the heterocyclic compounds.
Luke Camenzuli, Davide Benedetto Tiz, Nicola’ Agius, Konrad Szaciłowski, David C. Magri   +4 more
wiley   +1 more source

The crystal structures of 6′-(4-chlorophenyl)- and 6′-(4-methoxyphenyl)-6a′-nitro-6a′,6b′,7′,9′,10′,12a′-hexahydro-2H,6′H,8′H-spiro[acenaphthylene-1,12′-chromeno[3,4-a]indolizin]-2-one

Acta Crystallographica Section E: Crystallographic Communications, 2019
In the title compounds, C32H25ClN2O4 (I) and C33H28N2O5 (II), the six-membered pyran and piperidine rings adopt envelope and chair conformations, respectively. The five-membered pyrrolidine rings adopt twist conformations. Compound (II) crystallizes with
S. Syed Abuthahir, M. NizamMohideen, V. Viswanathan, D. Velmurugan, J. Nagasivarao   +4 more
doaj   +1 more source