Search results for "stereochemistry"

Synthesis of pillar[7]arene

2012

Abstract The first synthesis of pillar[7]arene is reported with two methods. Method A: the FeCl 3 -catalyzed condensation reaction of 1,4-dimethoxybenzene ( 1 ) with paraformaldehyde in CHCl 3 gave dimethoxypillar[7]arene ( 3 ). Method B: the p -toluenesulfonic acid catalyzed condensation reaction of 2,5-bis(benzyloxymethyl)-1,4-dimethoxybenzene ( 2 ) in CH 2 Cl 2 gave compound 3 . Demethylation of 3 with BBr 3 gave pillar[7]arene ( 4 ). The pillar[7]arene might be a perspective macrocyclic host in host–guest chemistry.

Antivirale Wirkstoffe, 17. Mitt. Oligocyclisch N-substituierte Lithocholsäureamide

1981

Von den durch Umsetzung der 3-Formyllithocholsaure mit den entsprechenden Aminen erhaltenen oligocyclisch N-substituierten Lithocholsaureamiden 1 uben insbesondere N-(2-Naphthyl)-3-formyllithocholsaureamid (1b) und N-(endo-2-Methylbicyclo[2.2.1]heptyl)lithocholsaureamid (1c) markante virustatische Wirkungen aus. Antiviral Drugs, XVII: Oligocyclically N-Substituted Lithocholic Amides Oligocyclically N-substituted lithocholic amides 1 are obtained by the reaction of 3-formyllithocholic acid with amines. N-(2-Naphthyl)-3-formyllithocholic amide (1b) and N-(endo-2-methylbicyclo-[2.2.1]heptyl)lithocholic amide (1c) exhibit marked virustatic activity.

Struktur-Wirkungs-Beziehungen bei Analeptica vom Typ des Nicethamids, 3. Mitt. Synthese von Analogen des 6-Methyl-nicethamids

1975

Als potentiell analeptisch wirksame Substanzen mit partiell fixierter funktioneller Gruppe werden strukturanaloge Amide, Imide und Lactame des 2-Methyl-nicethamids synthetisiert. Synthesis of 2-Methyl-Nicethamide Analogues. As potentially analeptically active substances with partially fixed functional groups, structural analogues of 2-methyl-nicethamide, in the form of amides, imides and lactams, are synthesized.

ChemInform Abstract: 1,3-Benzimidazoles. Part 2. 2-Aryl-Substituted Benzo-Anellated 5- Membered Heterocycles as Potential Effectors in the Cardiovasc…

2010

Scandium-catalyzed preparation of cytotoxic 3-functionalized quinolin-2-ones: Regioselective ring enlargement of isatins or imino isatins

2012

Trimethylsilyldiazomethane in the presence of catalytic amounts of Sc(OTf) 3 smoothly promotes the ring expansion of isatins or imino isatins to efficiently afford 3-functionalized quinolin-2-ones through controlled ring enlargement. Whereas the ring-expansion reaction of azetidine-2,3-diones led to the adduct resulting from migration of the carbonyl group, the ring-expansion reaction of oxindole derivatives gave the adduct resulting from migration of the aryl group. To rationalize the experimental observations, theoretical studies have been performed. Moreover, the biological activity of some of the synthesized heterocycles has been evaluated in four cancer cell lines. © 2012 Wiley-VCH Ver…

Red- and Blue-Shifts in Oligo(1,4-phenyleneethynylene)s Having Terminal Donor−Acceptor Substitutions

2004

Four series of oligo(1,4-phenyleneethynylene)s (OPEs), 1−4 (a−d), each having a terminal dialkylamino group as their electron donor, were prepared by applying Sonogashira−Hagihara reactions and a protecting group strategy. To study the influence that the push−pull effect has on the long-wavelength absorption, three of the four series of OPEs contain terminal acceptor groups (CN, CHO, NO2). Extending the conjugation (increasing the number of repeat units, n) lowers the energy E(n) of the electron transition in the purely donor-substituted series 1a−4a (bathochromic shift). This effect is superimposed in the push−pull series 1−4 (b−d) by the effect of the intramolecular charge transfer (ICT),…

ChemInform Abstract: A Sialyl-Lewis A-Asparagine Building Block for Glycopeptide-Synthesis.

2000

ChemInform Abstract: The Pyrrole Moiety as a Template for COX-1/COX-2 Inhibitors.

2000

ChemInform Abstract: Synthesis and Spectroscopic Characterizations of Both 1-Ethyl-4,8- dihydro-10-methoxy-3-methyl-8-R1-6-R2-dipyrazolo(3,4-b:4′,3′-…

2010

The non-selective methylation of compounds 3a-d using ethereal diazomethane, allowed the synthesis of isomers 4 and 5 which were useful intermediates for the preparation, by a simple approach, of the title compounds 7 and 9. A complete assignment of the chemical shifts to the carbon atoms of the compounds 7 and 9 was performed by different nmr experiments, such as DEPT and XHDEPT for onebond CH correlations and COLOC experiments for long-range C-H correlations.

Verbindungen mit potentiell positiv inotroper Wirkung, 1. Mitt. N-Substituierte 3-Amino-2-cyclopentenone aus partiell hydrierten 2-Phenanthrylaminen

1984

Die Darstellung partiell hydrierter 2-Phenanthrylamine und ihre Umsetzung mit 1,3-Cyclopentandion zu N-subst. 3-Amino-2-cyclopentenonen wird beschrieben. Compounds with Potentially Positive Inotropic Activity, I: N-Substituted 3-Amino-2-cyclopentenones from Partially Hydrogenated 2-Phenanthrylamines The synthesis of partially hydrogenated 2-phenanthrylamines and their reactions with 1,3-cyclopentanedione to N-substituted 3-amino-2-cyclopentenones is described.