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Exhaustive exploration of the conformational landscape of mono- and disubstituted five-membered rings by DFT and MP2 calculations
(Royal Society of Chemistry, 2019-07)
The conformational landscape of 22 different non, mono-, and disubstituted compounds with a fivemembered ring was thoroughly explored by ab initio (MP2) and DFT (B3LYP and M06-2X) methods with the 6-311+G** basis set. Our ...
Configurational assignments of diastereomeric γ-lactones using vicinal H-H NMR coupling constants and molecular modelling
(American Chemical Society, 2000-08)
The conformational features of four diastereomers of the γ-lactone 2-ethyl-4-methyl-5-oxotetrahydrofuran-3-carboxylic acid were investigated by calculations which included molecular mechanics (MM3), semiempirical (AM1) and ...
Conformation and stereodynamics of 1,2-diaryltetrahydropyrimidine and of its five- and seven-membered ring analogs
(Elsevier, 2011-11)
The 1-(2-nitrophenyl)-2-(2-methylphenyl)-1,4,5,6-tetrahydropyrimidine and its five- and seven-membered ring analogs were synthesized and their conformational properties investigated by low temperature NMR spectroscopy and ...
Recent advances in the solid-phase synthesis of N-heteroaromatic five membered rings
(Research Signpost, 2007)
Combinatorial chemistry and related high-speed syntheses are powerful tools for the discovery of new drugs. In particular, solid-phase organic synthesis (SPOS) is being widely used for the preparation of a large number of ...
A study about regioisomeric hydroquinones with multiple intramolecular hydrogen bonding
(MDPI AG, 2017)
A theoretical exploration about hydrogen bonding in a series of synthetic regioisomeric antitumor tricyclic hydroquinones is presented. The stabilization energy for the intramolecular hydrogen bond (IHB) formation in four ...
Five-Membered aromatic heterocycles in diels-alder cycloaddition reactions: Theoretical Studies as a Complement of the Experimental Researches
(Bentham Science Publishers, 2011-02)
The dienophilic behavior of electron-deficient substituted five-membered aromatic heterocyclices in polar cycloaddition reactions is studied from a theoretical point of view employing the global electrophilicity index to ...
Conformational and Stereodynamic Behavior of Five to Seven-membered 1-Aryl-2-iminoazacycloalkanes
(American Chemical Society Inc, 2019-03)
The stereodynamic behavior of 1-arylpyrrolidin-2-imines, having a C aryl -N stereogenic axis, has been studied by means of dynamic nuclear magnetic resonance and density functional theory calculations, evaluating the steric ...
A Diastereoselective Total Synthesis of trans-Trikentrin A: A Ring Contraction Approach
(AMER CHEMICAL SOC, 2008)
A new route to obtain the polyalkylated indole (+/-)-trans-trikentrin A was developed. The synthesis of this natural alkaloid features a thallium(III)mediated ring contraction reaction to obtain the trans-1,3-disubstituted ...