5962-96-9Relevant articles and documents
Asymmetric hydrogenation of maleic acid diesters and anhydrides
Bernasconi, Maurizio,Mueller, Marc-Andre,Pfaltz, Andreas
supporting information, p. 5385 - 5388 (2014/06/09)
Asymmetric hydrogenation of maleic and fumaric acid derivatives with iridium catalysts based on N,P ligands provides an efficient route to chiral enantioenriched succinates. A new catalyst derived from a 2,6-difluorophenyl- substituted pyridine-phosphinite ligand was developed and enables the conversion of a wide range of 2-alkyl and 2-arylmaleic acid diesters into the corresponding succinates in high enantiomeric purity. Mixtures of cis/trans substrates can be hydrogenated in an enantioconvergent fashion with high enantioselectivity, and further enhances the scope of this transformation. The products are valuable chiral building blocks with a structural motif found in many bioactive compounds, such as metalloproteinase inhibitors. An attractive enantioselective route to 2-alkyl- and 2-aryl-substituted succinic acid derivatives is opened up by the asymmetric hydrogenation of maleic and fumaric acid derivatives, using the new catalyst [Ir(cod)L]BArF, derived from a 2,6-difluorophenyl-substituted pyridine-phosphinite ligand. The products are valuable chiral building blocks having a structural motif found in many bioactive compounds. cod=1,5-cyclooctadiene.
Succinic anhydrides from epoxides
-
Page/Page column 24; 25; 26, (2013/07/25)
Catalysts and methods for the double carbonylation of epoxides are disclosed. Each epoxide molecule reacts with two molecules of carbon monoxide to produce a succinic anhydride. The reaction is facilitated by catalysts combining a Lewis acidic species with a transition metal carbonyl complex. The double carbonylation is achieved in single process by using reaction conditions under which both carbonylation reactions occur without the necessity of isolating or purifying the product of the first carbonylation.
Synthesis, nicotinic acetylcholine receptor binding, antinociceptive and seizure properties of methyllycaconitine analogs
Ivy Carroll,Ma, Wei,Navarro, Hernan A.,Abraham, Philip,Wolckenhauer, Scott A.,Damaj,Martin, Billy R.
, p. 678 - 685 (2007/10/03)
A series of methyllycaconitine (1a, MLA) analogs was synthesized where the (S)-2-methylsuccinimidobenzoyl group in MLA was replaced with a (R)-2-methyl, 2,2-dimethyl-, 2,3-dimethyl, 2-phenyl-, and 2-cyclohexylsuccinimidobenzoyl (1b-f) group. The analogs 1b-f were evaluated for their inhibition of [125I]iodo-MLA binding at rat brain α7 nicotinic acetylcholine receptors (nAChR). In order to determine selectivity, MLA and the analogs 1b-f were evaluated for inhibition of binding to rat brain α,β nAChR using [3H]epibatidine. At the α7 nAChR, MLA showed a Ki value of 0.87 nM, analogs 1b-e possessed Ki values of 1.67-2.16 nM, and 1f showed a Ki value of 26.8 nM. Surprisingly, the analog 1e containing the large phenyl substituent (Ki = 1.67 nM) possessed the highest affinity. None of the compounds possessed appreciable affinity for α,β nAChRs. MLA antagonized nicotine-induced seizures with an AD50 = 2 mg/kg. None of the MLA analogs were as potent as MLA in this assay. MLA and all of the MLA analogs, with the exception of 1b, antagonized nicotine's antinociceptive effects in the tail-flick assay. Compound 1c (Ki = 1.78 nM at α7 nAChR) with an AD50 value of 1.8 mg/kg was 6.7 times more potent than MLA (AD50 = 12 mg/kg) in antagonizing nicotine's antinociceptive effects but was 5-fold less potent than MLA in blocking nicotine-induced seizures. Since MLA has been reported to show neuroprotection against β-amyloid1-42, these new analogs which have high α7 nAChR affinity and good selectivity relative to α,β nAChRs will be useful biological tools for studying the effects of α7 nAChR antagonist and neuroprotection.
