132980-99-5Relevant articles and documents
GOLD COMPLEXES
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Paragraph 0112, (2013/03/26)
Gold (I) hydroxide complexes of the form Z-Au-OH and digold complexes of the form Z—Au-(μOH)—Au—Z where groups Z are two electron donors are provided. The groups Z may be carbenes, for example nitrogen containing heterocyclic carbenes (NHCs), phosphines or phosphites. The complexes can be used as catalysts, for example in reactions such as hydration of nitriles, skeletal arrangement of enynes, alkoxycyclisation of enynes, alkyne hydration, the Meyer-Shuster reaction, 3,3′ rearrangement of allylic acetates, cyclisation of propargylic acetates, Beckman rearrangements and hydroamination. The complexes can be used in medicine, for example in the treatment of cancer.
Straightforward zinc-catalyzed transformation of aldehydes and hydroxylamine hydrochloride to nitriles
Enthaler, Stephan,Weidauer, Maik,Schr?der, Fanny
experimental part, p. 882 - 885 (2012/03/26)
In the present study, the zinc-catalyzed dehydration of a range of in situ generated aldoximes, available by the reaction of aldehydes and hydroxylamine hydrochloride, has been explored. After investigating various reaction parameters, with Zn(OTf)2 an excellent and easily accessible pre-catalyst was obtained. The system was highly active and dehydrated a broad range of aldoximes selectively to the corresponding nitriles under mild reaction conditions.
[{Au(IPr)}2(μ-OH)]X complexes: Synthetic, structural and catalytic studies
Ramon, Ruben S.,Gaillard, Sylvain,Poater, Albert,Cavallo, Luigi,Slawin, Alexandra M. Z.,Nolan, Steven P.
experimental part, p. 1238 - 1246 (2011/03/20)
The synthesis of a series of dinuclear gold hydroxide complexes has been achieved. These complexes of type [{Au(IPr)}2(Iμ-OH)]X (X=BF 4, NTf2, OTf, FABA, SbF6; IPr=2,6- bis(disopropylphenyl)imidazol-2-ylidene; NTf2= bis(trifluoromethanesulfonyl)imidate; OTf=trifluoromethanesulfonate; FABA=tetrakis(pentafluorophenyl)borate) are easily formed in the presence of water and prove highly efficient in the catalytic hydration of nitriles. Their facile formation in aqueous media suggests they are of relevance in gold-catalyzed reactions involving water. Additionally, a series of [Au(IPr)(NCR)][BF4] (R=alkyl, aryl) complexes was synthesized as they possibly occur as intermediates in the catalytic reaction mechanism. 1H and 13C NMR data as well as key bond lengths obtained by X-ray diffraction studies are compared and reveal an interesting structure-activity relationship. The collected data indicate a negligible effect of the nature of the nitrile on the reactivity of [Au(L)(NCR)][X] complexes in catalysis.
Gold Activation of Nitriles: Catalytic Hydration to Amides
Ramon, Ruben S.,Marion, Nicolas,Nolan, Steven P.
supporting information; experimental part, p. 8695 - 8697 (2010/03/24)
A gold-based catalytic system that efficiently mediates the hydration of a broad spectrum of nitriles, including aromatic, heteroaromatic and aliphatic examples and efficiently catalyze the hydration of a range of organonitriles has been reported. Nitriles are considered inert in the context gold catalysis and have only been used as reaction solvent or as throw-away ligands in well-defined cationic gold catalysis. The obtained product was purified by flash chromatography using a gradient of pentane/ethyl acetate and compound 1 was isolated as a colorless solid. Aromatic substrates bearing two nitrile groups as in rn-benzenedinitrile and p-benzenedinitrile underwent double nitrile hydration and afforded excellent yields in the corresponding diamides. There is high relevance for the use of cationic gold complexes bearing such ligands and should have important implications in catalysis.
Prodrugs of neuron-selective monoamine oxidase inhibitors: Amino acid derivatives of 1-(4-aminophenyl)-2-aminopropanes
Florvall, Lennart,Fagervall, Ingrid,Larsson, Lars-Gunnar,Ross, Svante B.
, p. 137 - 151 (2007/10/03)
Six amino acid derivatives of 1-(4-aminophenyl)-2-aminopropanes and their parent amines were synthezised and tested for their potency and selectivity in inhibiting monoamine oxidase (MAO) in vitro and in vivo. The amino acid derivatives were 300-1000 times less potent than the parent amines in inhibiting the MAO-A activity in a rat brain mitochondrial preparation in vitro. All compounds, except the (R)-valinamide derivative (22), were potent inhibitors of MAO in the rat brain in vivo and were, like the parent amines markedly more potent within the monoaminergic neurons than in other neurons. The glycinamide derivative 7 showed the largest difference between intra- and extra-neuronal inhibition in serotonergic neurons. The time course of the inhibitory effect of 7 in vivo showed that it is a reversible inhibitor with a long duration.
Synthesis and anthelmintic activity of 3'-benzoylurea derivatives of 6-phenyl-2,3,5,6-tetrahydroimidazo[2,1-b]thiazole
Weikert,Bingham Jr.,Emanuel,Fraser-Smith,Loughhead,Nelson,Poulton
, p. 1630 - 1633 (2007/10/02)
Reaction of 3-amino derivatives of the nematocides tetramisole and levamisole with variously substituted benzoylisocyanates gave a series of benzoylureas I which were tested for activity against helminths and ectoparasites. Compounds bearing 2,6-difluoro and 4-trifluoromethyl substituents had potent nematocidal activity in both mice and sheep. No antiectoparasitic activity was observed.
Histamine analogues. 33rd communication: 2-phenylhistamines with high histamine H1-agonistic activity
Zingel, V.,Elz, S.,Schunack, W.
, p. 673 - 680 (2007/10/02)
2-Phenylhistamines with various substituents at the phenyl ring were synthesized and the influence of substitution in ortho, meta or para position on histamine H1-agonistic activity was investigated.Compounds with high activity occured in the meta phenyl series.Increased activity in the guinea-pig ileum assay was achieved by monosubstitution with halogen on the phenyl ring. 2-ethanamine (12) is the most potent highly selective H1-agonist known so far, showing 87percent relative potency compared with histamine and full efficacy at theH1-receptor.Relative activities of the 3-chloro analogue (11) and the 3-methyl analogue (13) are 81percent and 29percent, respectively.Histamine H2-activity could not be detected. 2-Phenylhistamines are available via reaction of the corresponding benzimidates with 2-oxo-4-phthalimido-1-butyl acetate (6) in liquid ammonia.