0000000000147265

AUTHOR

Erich Kleinpeter

showing 3 related works from this author

Synthesis and Conformational Analysis of Tetrahydroisoquinoline-Fused 1,3,2-Oxazaphospholidines and 1,2,3-Oxathiazol­idines

2008

The cyclizations of tetrahydroisoquinoline 1,2-amino alcohols with phenylphosphonic dichloride, bis(2-chloroethyl)phosphoramidic dichloride, thionyl chloride and sulfuryl chloride were utilized to synthesize 1,5,6,10b-tetrahydro-1,3,2-oxazaphospholo[4,3-a]isoquinolines (2, 3), 1,5,10,10a-tetrahydro-1,3,2-oxazaphospholo[3,4-b]isoquinolines (8, 9), 1,5,6,10b-tetrahydro-1,2,3-oxathiazolo[4,3-a]isoquinolines (4–6) anda 1,5,10,10a-tetrahydro-1,2,3-oxathiazolo[3,4-b]isoquinoline (11), which are the first representatives of these ring systems. NMR spectroscopic analysis revealed the existence of conformational equilibria that are fast on the NMR timescale. Theoretical DFT calculations pointed to t…

chemistry.chemical_compoundThionyl chloridechemistryComputational chemistryStereochemistryTetrahydroisoquinolineOrganic ChemistrySulfuryl chloridePhysical and Theoretical ChemistryIsoquinolineRing (chemistry)Conformational isomerismEuropean Journal of Organic Chemistry
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Synthesis and stereochemical studies of 1- and 2-phenyl-substituted 1,3-oxazino[4,3-a]isoquinoline derivatives

2003

Abstract Starting from the 1′- or 2′-phenyl-substituted 1-(2′-hydroxyethyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline diastereomers 3 and 6 , 4-unsubstituted and 4-(p-nitrophenyl)- and 4-oxo-substituted 1-phenyl- and 2-phenyl-9,10-dimethoxy-2H,4H-1,6,7,11b-tetrahydro-1,3-oxazino[4,3-a]isoquinolines ( 7–12 ) were prepared. The relative configurations and the predominant conformations of the products were determined by NMR spectroscopy, by quantum chemical calculations and, for (2R∗,4S∗,11bR∗)-9,10-dimethoxy-4-(p-nitrophenyl)-2-phenyl-2H,4H-1,6,7,11b-tetrahydro-1,3-oxazino[4,3-a]isoquinoline ( 11 ), by X-ray diffraction.

DiffractionQuantum chemicalchemistry.chemical_classificationStereochemistryChemistryOrganic ChemistryDiastereomerOxazinesNuclear magnetic resonance spectroscopyBiochemistrychemistry.chemical_compoundComputational chemistryDrug DiscoveryIsoquinolineTetrahedron
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Preparation and Structure of Diexo-Oxanorbornane-fused 1,3-Heterocycles

2004

Via the reaction of diexo-oxanorbornanedicarboxylic anhydride with toluene, the diexo-aroylcarboxylic acid (3a) was prepared, which exists partly as the tautomeric lactol (3b). With bifunctional reagents, 3a yields fused heterocycles containing three-six rings. Thus, alkylenediamines result in imidazole- and 1,3-diazepine-fused oxygen- bridged isoindolones (6a,b), alkanolamines form the oxazole- and 1,3-oxazine-fused oxanorbornene derivatives (7a-c), and o-phenylenediamine undergoes cyclization to furnish the condensed benzimidazole (8). The reaction of 3a with diexo- aminonorbornanecarbohydrazide yields a pyrimidopyridazine containing six condensed rings (9). In a similar reaction with die…

PharmacologyCyclopentadieneLactolArylOrganic ChemistrySubstituentRetro-Diels–Alder reactionMedicinal chemistryTautomerAnalytical Chemistrychemistry.chemical_compoundchemistryInstitut für ChemieOrganic chemistryImidazoleOxazoleHETEROCYCLES
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