Search results for "Amide"

A New Tandem Cross Metathesis-Intramolecular Aza-Michael Reaction for the Synthesis of α,α-Difluorinated Lactams

2012

A new tandem cross metathesis–intramolecular aza-Michael­ reaction in which an α,α-difluorinated amide serves as a source of nucleophilic nitrogen is described. This process gives rise to a new family of fluorinated γ- and δ-lactams. The tandem protocol is catalyzed by the Hoveyda–Grubbs second-generation ruthenium catalyst with titanium(IV) tetraisopropoxide as a co-catalyst and it is highly efficient when conjugated ketones are used as the Michael acceptors. With conjugated esters, however, it is necessary to perform a step-by-step procedure in which the cyclization event is activated by the addition of a base. An asymmetric version of the process is also evaluated.

Stereoselective Synthesis of 3-Substituted and 3,4-Disubstituted Piperidine und Piperidin-2-one Derivatives

2012

The stereoselective synthesis of 3-substituted and 3,4-disubstituted piperidine and piperidin-2-one derivatives was achieved starting from 2-pyridone. After N-galactosylation and subsequent O-silylation, nucleophilic addition of organometallic reagents proceeded with high regio- and stereoselectivity at 4-position. Substituents at position 3 were stereoselectively introduced by reaction of electrophiles with amide enolates of the N-galactosyl-2-piperidones.

COMPOSICIÓN QUIMICA DE LAS HOJAS y SEMILLAS DE SACHA INCHI (Plukenetia volubilis L.); OLEAMIDA

2021

El estudio se realiza con el objeto de identificar el tipo de alcaloide, protoalcaloide opseudoalcaloide, que puedan ser cuantificables en las hojas y en la torta desemillas tostadas y desengrasadas de la especie Plukenetia volubilis L. y demostrar que su presencia no representa un riesgo para la salud. La metodología utilizada está basada en protometría de acuerdo a la Farmacopea Francesa y Europea, así como la utilización de técnicas de UHPLC-MS/MS y GC-MS que han permitido identificar y cuantificar un compuesto endógeno que revela las características de la cis-9-octadecenamida (oleamida), estructura similar a la anandamida; ligando endógeno de receptores cannabinoides en concentraciones …

Thermoresponsive hyperbranched polyethylenimines with isobutyramide functional groups

2007

Calixarenes as Stoppers in Rotaxanes

1998

The synthesis of the amide-based rotaxane 7a bearing calix[4]arene blocking groups is described for the first time. While rotaxane formation fails if a calix[4]arene is functionalized at the upper rim with only an amino or methylamino group lacking any spacer, the prolonged amine 5a works successfully as stopper unit preventing dethreading of the dimeric wheel 1a by its size. Rotaxane formation of 8b was observed only by MALDI-TOF mass spectrometry of the reaction mixture of the amine 5b, the axle 6 and 1a. With the larger trimeric wheel 1b no stable rotaxane could be obtained. It either does not act as a concave template or its opening is too wide, even for the bulky calixarene stoppers.

Oligamide mit definierter verzweigung. Lineare und cyclische oligomere. XIV.

1965

Synthese und chemische Eigenschaften des ersten verzweigten, molekulareinheitlichen Oligoamids mit definierter Struktur werden beschrieben. N,N-[Di-(ϵ-aminocaproyl)]-ϵ-aminocapronsaure (V), ein Oligomeres aus drei Aminocapronsaureresten mit einer Acylamidverzweigung, wurde durch Acylierung der Saureamidgruppe einer amino- und carboxyl-geschutzten Di-ϵ-aminocapronsaure mit einem N-geschutzten ϵ-Aminocaproylchlorid und nachfolgender Abspaltung aller Schutzgruppen als Hydrochlorid bzw. Tetraphenylborat in analysenreiner Form gewonnen. In neutralem und alkalischem Medium erleidet es bereits unter milden Bedingungen Polykondensation. The synthesis and chemical properties of the first branched, m…

ChemInform Abstract: Highly Enantioselective Copper(I)-Catalyzed Conjugate Addition of Terminal Alkynes to 1,1-Difluoro-1-(phenylsulfonyl)-3-en-2-one…

2014

A highly enantioselective copper-catalyzed conjugate alkynylation of monoactivated enones, namely 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones, is described. The reaction products are obtained with good yields and excellent enantioselectivities (from 92 to 99% ee). The β-alkynylated difluoro(phenylsulfonyl) ketones can be converted into the corresponding β-alkynylated difluoro- and trifluoromethyl ketones, esters and amides. This is the first example on the use of 1,1-difluoro-1-(phenylsulfonyl)-3-en-2-ones as substrates in an enantioselective reaction, which have been shown to be new ester/amide surrogates.

Ultrarotspektroskopische Untersuchungen an Copolymeren des Acroleins. Polymere Acroleine. 12. Mitteilung

1959

Die UR-Spektren folgender Copolymerisate werden mitgeteilt: Acrolein/Acrylnitril, Acrolein/Acrylsauremethylester, Acrolein/Vinylaceatat und Acrolein/Acrylamid. Am Beispiel der Copolymeren von Acrolein und Acrylnitril wird gezeigt, das man durch Intensitatsmessungen der UR-Absorptionsbanden zu quantitativen Aussagen uber Anordnung und Lange der einzelnen Segmente im Copolymeren gelangen kann. Die so erhaltenen Ergebnisse stimmen mit statistischen Berechnungen uberein. The infrared spectra of the following copolymers are given: acrolein/acrylonitrile, acrolein/methylacrylate, acrolein/vinylaetate and acrolein/acrylamide. There is shown by the example of copolymers of acrolein and acrylonitile…

Über die copolymerisation des acroleins und des methacroleins in homogener lösung. Polymere acroleine. 25. Mitt.

1962

Die Copolymerisation des Acroleins und des Methacroleins in Dimethylformamid sowie in Dioxan wird beschrieben. Die Parameter folgender Systeme wurden bestimmt: Acrolein/Acrylnitril (r1 = 1,60; r2 = 0,52); Acrolein/Acrylamid (r1 = 1,69; r2 = 0,21); Acrolein/Methacrylnitril (r1 = 0,72; r2 = 1,20); Acrolein/2-Vinylpyridin (r1 = 4; r2 = 0) und Methacrolein/Methacrylnitril (r1 = 1,78; r2 = 0,40). Die Berechnung der Q-und e-Werte bzw. der q- und ϵ-Werte ergab fur Acrolein: Q = 0,64; e = 0,61; q = -2,8 kcal/Mol; ϵ = 0,19 = 10−10 elektrostatische Einheiten und fur Methacrolein: Q = 1,59; e = 0,36; q = −3,4 kcal/Mol; ϵ = 0,11 = 10−10 elektrostatische Einheiten. The copolymerisation of acrolein and m…

Tumorhemmende Wirkstoffe, 12. Mitt. 2-Ureido-4(3H)-pyrimidinone

1981

Aus der Kondensation von Guanidincarbonsaureamid (1) mit den β-Ketocarbonsaureestern 2a–h resultieren die 2-Ureido-4(3H)-pyrimidinone 3a–h. Die Ubertragbarkeit dieser Reaktionsweise auf cyclische Ketocarbonsaureester geht aus der zu 2-Ureido-5,6,7,8-tetrahydro-4(3 H)-chinazolon (3i) fuhrenden Kondensation von 1 mit 2-Oxocyclohexancarbonsaureethylester (2i) hervor. Besonders 3h vermag turmorhemmende Effekte auszulosen. Tumor Inhibitory Agents, XII: 2-Ureido-4(3H)-pyrimidinones The condensation of guanidinecarboxylic amide (1) with the β-ketocarboxylates 2a-h leads to the 2-ureido-4(3H)-pyrimidinones 3a–h. The applicability of this reactin to cyclic ketocarboxylates is demonstrated by the con…