Search results for "Derivatives"
showing 10 items of 432 documents
A Short Synthesis of Polysubstituted Pyrrolidines via α-(Alkylideneamino)nitriles
2004
α-(Alkylideneamino)nitriles can be deprotonated under mild conditions. Their conjugated anions react with enones in a 1,4-addition to yield δ-keto-α-(alkylideneamino)nitriles which in turn can be reduced to form pyrrolidines in a one-pot reaction sequence.
New Fluorinated 1,3-Vinylogous Amidines as Versatile Intermediates: Synthesis of Fluorinated Pyrimidin-2(1H)-ones.
2006
The condensation of the azaenolates derived from readily available ketimines with fluorinated nitriles offers an efficient and straightforward entry to new fluorinated 1,3-vinylogous amidines. These versatile compounds, in turn, react with triphosgene to yield new fluorinated pyrimidin-2(1H)-ones in high yields.
An In Vitro Experiment for Postmortem Vascular Permeation. The Passage of Morphine and Morphine Glucuronides Across a Vascular Wall
1997
A venous blood sample taken at autopsy cannot be considered to represent the antemortem blood concentration of a particular substance. Autolytic processes cause disintegration and increasing permeability of the physiological and anatomical barriers such as vascular walls and lead to changes in substance concentrations. In the present study, the experimental design represents an in vitro postmortem simulation of a drug substance crossing a venous wall. The postmortem behavior of morphine, morphine-3- and morphine-6-glucuronide was investigated. A Chien-Valia-diffusion chamber with a patch of inferior vena cava as diffusion barrier was used. For optimal simulation of postmortem events, vein s…
Free energy and states of fractional-order hereditariness
2014
AbstractComplex materials, often encountered in recent engineering and material sciences applications, show no complete separations between solid and fluid phases. This aspect is reflected in the continuous relaxation time spectra recorded in cyclic load tests. As a consequence the material free energy cannot be defined in a unique manner yielding a significative lack of knowledge of the maximum recoverable work that can extracted from the material. The non-uniqueness of the free energy function is removed in the paper for power-laws relaxation/creep function by using a recently proposed mechanical analogue to fractional-order hereditariness.
Highly Enantioselective Friedel−Crafts Alkylations of Indoles with Simple Enones Catalyzed by Zirconium(IV)−BINOL Complexes
2007
Complexes of BINOL-based ligands with Zr(OtBu)4 catalyze the Friedel-Crafts alkylation reaction of indoles and pyrrole with nonchelating beta-substituted alpha,beta-enones at room temperature affording the expected products with good yields and ee above 95% in most of the studied examples.
ChemInform Abstract: Enantioselective Synthesis of Tertiary Alcohols Through a Zirconium-Catalyzed Friedel-Crafts Alkylation of Pyrroles with α-Ketoe…
2011
Chiral complexes of 1,1′-bi-2-naphthol-based ligands with zirconium tert-butoxide catalyze the Friedel–Crafts alkylation of pyrroles with α-ketoesters to afford tertiary alcohols in good yields and ee up to 98%. The reaction is also of application to 4,7-dihydroindole to give C2-alkylated indoles after oxidation with p-benzoquinone.
ChemInform Abstract: Synthesis of Functionalized Indoles with a Trifluoromethyl-Substituted Stereogenic Tertiary Carbon Atom Through an Enantioselect…
2010
Chiral complexes of BINOL-based ligands with zirconium tert-butoxide catalyze the Friedel-Crafts alkylation reaction of indoles with beta-trifluoromethyl-alpha,beta-unsaturated ketones to give functionalized indoles with an asymmetric tertiary carbon center attached to a trifluoromethyl group. The reaction can be applied to a large number of substituted alpha-trifluoromethyl enones and substituted indoles. The expected products were obtained with good yields and ees of up to 99%.
New 1,2,4-oxadiazole nortopsentin derivatives with cytotoxic activity
2019
New analogs of nortopsentin, a natural 2,4-bis(3&prime
Synthesized benzamido derivatives exert antiproliferative effects by DNA damage and ROS generation.
2016
In this study we explored the effect and the biological action of synthesized benzamido derivatives bearing the (1S,2S)-2-phenyl-cyclopropane-1-carboxamido, 1,1'-biphen-2-carboxamido and 1,1'-biphen-4-carboxamido moieties on K562, a human leukemia cell line. Among the synthesized compounds a particular antiproliferative action was observed with the benzamido derivative bearing the 2-1,1'-biphenyl moiety with the substitution at the 5 position of the benzamido moiety with iodine. This compound showed cytotoxic effects in K562 leukemic cells at nanomolar concentrations and was, therefore, chosen as compound to explore its mode of action. Our analyses provided evidence that this benzamido deri…
3-(6-Phenylimidazo [2,1-b][1,3,4]thiadiazol-2-yl)-1H-Indole Derivatives as New Anticancer Agents in the Treatment of Pancreatic Ductal Adenocarcinoma
2020
A new series of imidazo[2,1-b][1,3,4]thiadiazole derivatives was efficiently synthesized and screened for their in vitro antiproliferative activity on a panel of pancreatic ductal adenocarcinoma (PDAC) cells, including SUIT-2, Capan-1 and Panc-1. Compounds 9c and 9l, showed relevant in vitro antiproliferative activity on all three pre-clinical models with half maximal inhibitory concentration (IC50) ranging from 5.11 to 10.8 µ