Search results for "Moiety"
showing 10 items of 621 documents
Synthesis and biological evaluation of 2-(3 ',4 ',5 '-trimethoxybenzoyl)-3-amino 5-aryl thiophenes as a new class of tubulin inhibitors
2006
2-(3',4',5'-Trimethoxybenzoyl)-3-amino-5-aryl/heteroaryl thiophene derivatives were synthesized and evaluated for antiproliferative activity, inhibition of tubulin polymerization, and cell cycle effects. SARs were elucidated with various substitutions on the aryl moiety 5-position of the thienyl ring. Substituents at the para-position of the 5-phenyl group showed antiproliferative activity in the order of F=CH(3) > OCH(3)=Br=NO(2) > CF(3)=I > OEt. Several of these compounds led to arrest of HL-60 cells in the G2/M phase of the cell cycle and induction of apoptosis.
ChemInform Abstract: Solution versus Fluorous versus Solid-Phase Synthesis of 2,5-Disubstituted 1,3-Azoles. Preliminary Antibacterial Activity Studie…
2010
A small library of compounds with an oxa(thia)zole scaffold and structural diversity in both positions 2 and 5 has been synthesized. Double acylation of a protected glycine affords intermediate alpha-amido-beta-ketoesters, which in turn can be dehydrated to afford 1,3-oxazoles or reacted with Lawesson's reagent to furnish 1,3-thiazoles. This procedure was designed with its adaptation to fluorous techniques in mind. Thus, when a protected glycine with a fluorous tag in the ester moiety is used as a starting material, the synthesis can be easily completed without column chromatography purification of intermediate compounds with good to excellent yields, thus affording a suitable entry to the …
Double asymmetric intramolecular aza-Michael reaction: a convenient strategy for the synthesis of quinolizidine alkaloids.
2021
A new methodology to access the quinolizidine skeleton in an asymmetric fashion was devised. It involves two consecutive intramolecular aza-Michael reactions of sulfinyl amines bearing a bis-enone moiety, in turn generated by a monodirectional cross metathesis reaction. The sequence, which takes place with excellent yields and diastereocontrol, was applied to the total synthesis of alkaloids lasubine I and myrtine.
Oxidation of carbidopa by tyrosinase and its effect on murine melanoma
2009
Oxidation of the anti-Parkinsonian agent carbidopa by tyrosinase was investigated. The products of this reaction were identified as 3-(3,4-dihydroxyphenyl)-2-methylpropanoic acid and 6,7-dihydroxy-3-methylcinnoline. These results demonstrate that after oxidation of the catechol moiety to an o-quinone either a redox exchange with the hydrazine group or a cyclization reaction occur. The cyclization product underwent additional oxidation reactions leading to aromatization. The cyclization reaction is undesired in the case of hydrazine-containing anti-melanoma prodrugs and will have to be taken into account in designing such compounds. Carbidopa was tested against B16(F10) melanoma cells in cul…
A New Valence Tautomerism Example in an Electroactive Ferrocene Substituted Triphenylmethyl Radical
2003
A new molecular system combining an open-shell organic radical that acts as an acceptor group, different from an o-quinone moiety, covalently linked to a ferrocene moiety, acting as the donor group, is shown to exhibit valence tautomerism.
Preparation and XAFS studies of organotin(IV) complexes with adenosine and related compounds and calf thymus DNA
2007
Complexes of adenosine and related compounds (adenosine-5’-monophosphate, adenosine-5’-triphosphate and pyridoxal-5-phosphate) with Bu2SnO and/or BuSnCl2 were prepared in the solid state. The compositions of the complexes were determined by standard analytical methods. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1. The FT-IR spectra demonstrated that Bu2SnO reacts with the D-ribose moiety of the ligands, while Bu2SnCl2 is coordinated to the deprotonated phosphate group. The basic part of the ligands does not participate directly in complex formation. Comparison of the experimental Mossbauer Δ (quadrupole splitting) values with those calcul…
Synthesis of new asymmetric xanthene dyes via catalyst-free SNAr with sulfur nucleophiles
2014
Addition of a single functional handle to the tricyclic moiety of fluorescein results in asymmetric xanthene dyes. Our synthesis of a new class of asymmetric xanthenes proceeds via an unusual SNAr with sulfur nucleophiles on electron rich aromatic xanthenes scaffolds in the absence of a metal catalyst. The resulting 3'-thioethers exhibit high photostability and are conveniently converted into reactive dyes for macromolecule labelling.
ChemInform Abstract: Synthesis of New Asymmetric Xanthene Dyes via Catalyst-Free SNAr with Sulfur Nucleophiles.
2014
Addition of a single functional handle to the tricyclic moiety of fluorescein results in asymmetric xanthene dyes. Our synthesis of a new class of asymmetric xanthenes proceeds via an unusual SNAr with sulfur nucleophiles on electron rich aromatic xanthenes scaffolds in the absence of a metal catalyst. The resulting 3′-thioethers exhibit high photostability and are conveniently converted into reactive dyes for macromolecule labelling.
Evaluation of Fused Pyrrolothiazole Systems as Correctors of Mutant CFTR Protein.
2021
Cystic fibrosis (CF) is a genetic disease caused by mutations that impair the function of the CFTR chloride channel. The most frequent mutation, F508del, causes misfolding and premature degradation of CFTR protein. This defect can be overcome with pharmacological agents named “correctors”. So far, at least three different classes of correctors have been identified based on the additive/synergistic effects that are obtained when compounds of different classes are combined together. The development of class 2 correctors has lagged behind that of compounds belonging to the other classes. It was shown that the efficacy of the prototypical class 2 corrector, the bithiazole corr-4a, could be impr…
Synthesis of bis(diphenylphosphinocyclopentadienyl) yttrium chloride complexes and heterodimetallic derivatives. X-ray structure of bis[(μ-chloro)bis…
1996
Abstract Reaction of lithium diphenylphosphinocyclopentadienide with YCl 3 or YCl 3 (THF) 3 and working lead to the formation of three yttrocene phosphines: the lithium metal adduct isolated as (Ph 2 PC 5 H 4 ) 2 Y(μ-Cl) 2 Li(THF) 2 · 0.5 LiCl ( 1 ), the chloride-bridged dimeric species {(Ph 2 PC 5 H 4 ) 2 Y(μ-Cl)} 2 ( 2 ), and the coordinated monometal species [(Ph 2 PC 5 H 4 ) 2 YCl(THF)] ( 3 ). The X-ray structure of 2 is remarkable in that the crystal exhibits two independent chloride-bridged dimers that differ in the arrangement ( syn, anti ) of the diphenylphosphino groups. Chelation of phosphorus atoms to a molydenum carbonyl moiety is also reported.