Search results for "deriva"

Synthese und biochemische Eigenschaften substituierter Phenoxy- und Anilino-1,3,5-triazine

1983

Die nucleophile Substitution eines Chloratoms in 2,4-Dichlor-6-diethylamino-1,3,5-triazin (1) durch die Hydroxyacetophenone 2a–c fuhrt zu den 2-Acetylphenoxy-4-chlor-6-diethylamino-1,3,5-triazinen 3a–c. Analog geht aus der Umsetzung von 1 mit 4-Fluoranilin (4a) das Monoanilinoderivat 5a hervor; dagegen bildet sich unter den gleichen Reaktionsbedingungen aus 1 und 2-Fluoranilin (4b) das Dianilinoderivat 5b. Strukturtyp 3 zeichnet sich durch antimykotische und Antiprotozoenwirksamkeit aus, wahrend 5 herbizide Wirkungen auszulosen vermag. Synthesis and Biochemical Properties of Substituted Phenoxy- and Anilino-1,3,5-triazines The nucleophilic substitution of one chlorine atom in 2,4-dichloro-6…

ChemInform Abstract: Modular One-Pot Synthesis of Tetrasubstituted Pyrroles from α-(Alkylideneamino)nitriles.

2008

2,3,4,5-Tetrasubstituted pyrroles have been prepared with high regioselectivity by a formal cycloaddition of α-(alkylideneamino)nitriles and nitroolefins followed by elimination of HCN and HNO2. The reaction allows the convergent construction of the pyrrole ring in four steps from a nitroalkane and three aldehydes.

Coordinative Stabilization ofCyclo-Tetratellurium as[Te4{Cr(CO)5}4]: The First Organometallic Derivative of a Tellurium Allotrope

1997

ChemInform Abstract: Synthesis of the New Ring System Pyrrolizino[2,3-b]indol-4(5H)-one.

2011

A variety of pyrrolizinoindolones (VIII) is synthesized as demonstrated for derivative (VIIIa).

Design of guanidinium porphyrins as potential G-quadruplex ligands

2012

We report herein an easy and smooth synthesis of two novel tetra-meso-substituted porphyrins bearing terminal guanidinium functionalities. These two guanidine derivatives are the porphyrin-based analogs of ZnPC , a closely related phthalocyanine-based molecule with four guanidinium arms already reported as an efficient G-quadruplex ligand.

The reaction of amino-imidazoles, -pyrazoles and -triazoles with α,β-unsaturated nitriles

2005

The reactions of α,β-unsaturated nitriles (1, 9, 12) as bielectrophiles with aminoazoles (2, 4, 6) as binu-cleophiles were investigated. Acrylonitrile (1) reacts almost exclusively in a chemoselective Michael-type addition yielding the substituted azoles 3, 5 and 7, respectively. Cinnamonitriles 9a,b behave in a similar way, but the free CN group adds a second molecule 4 yielding 10a,b and its cyclocondensation product 11a,b as minor component. The attempted formation of azolopyrimidines is best achieved by the reaction of the benzylidenemalononitriles 12a - f with 2 or 4. The process is chemo- and regioselective. The structure determinations were based on NMR measurements including DEFT, C…

ChemInform Abstract: 1,2,4-Oxadiazole Rearrangements Involving an NNC Side-Chain Sequence.

2010

The thermal rearrangement of N-1,2,4-oxadiazol-3-yl-hydrazones into 1,2,4-triazole derivatives is reported. This represents the first example of a three-atom side-chain rearrangement involving an NNC sequence linked at the C(3) of the oxadiazole. The reactions carried out under solvent-free conditions produced good to high yields of the final products.

ChemInform Abstract: Facile Synthesis of Pyrazoles and Pyrroles via Thermolysis of Tetrazolo[1,5-b]pyridazines, Tetrazolo[1,5-a]pyrimidines and Tetra…

2010

Abstract A simple and high yielding preparation of pyrazoles and pyrroles is described. Thermolysis of tetrazolo[1,5- b ]pyridazines, tetrazolo[1,5- a ]pyrimidines and tetrazolo[1,5- a ]pyridines allowed easy ring contraction thus providing a facile preparation of cyanopyrazole and cyanopyrrole heterocycles. Since the cyano group is a versatile precursor of other functionalities, the reaction appears of particular interest for the construction of a variety of pyrazoles and pyrroles. The simple preparation of the starting tetrazole derivatives, the relatively mild conditions employed, and the very short reaction times make this versatile procedure of great synthetic utility and applicable bo…

ChemInform Abstract: Polycondensed Nitrogen Heterocycles. Part 24. Pyrrolo(3,4-c) isoquinolinone by Thermal Rearrangement of a Pyrrolylbenzotriazinon…

2010

Rearrangement under acidic conditions of the pyrrolylbenzotriazinone 7 afforded the pyrrolylbenzamides 10 and 11. By thermal rearrangement instead, the first fully aromatic derivative of the pyrrolo[3,4-c]isoquinoline ring system 9 was obtained.

Nickel as a Lewis Base in a T‐Shaped Nickel(0) Germylene Complex Incorporating a Flexible Bis(NHC) Ligand

2018

Flexible, chelating bis(NHC) ligand 2, able to accommodate both cis- and trans-coordination modes, was used to synthesize (2)Ni(η 2 -cod), 3. In reaction with GeCl2, this produced (2)NiGeCl2, 4, featuring a T-shaped Ni(0) and a pyramidal Ge center. Complex 4 could also be prepared from [(2)GeCl]Cl, 5, and Ni(cod)2, in a reaction that formally involved Ni-Ge transmetalation, followed by coordination of the extruded GeCl2 moiety to Ni. A computational analysis showed that 4 possesses considerable multiconfigurational character and the Ni→Ge bond is formed through σ-donation from the Ni 4s, 4p, and 3d orbitals to Ge. (NHC)2Ni(cod) complexes 9 and 10, as well as (NHC)2GeCl2 derivative 11, incor…