21190-34-1Relevant articles and documents
Synthesis and X-ray crystal structure of 1,4-dihydro-2,6-dimethyl-4-(2'-isopropylphenyl)-3,5-pyridine-dicarboxy lic acid dimethyl ester: A nifedipine analogue
Palmer, Robert B.,Andersen, Niels H.
, p. 2173 - 2176 (1996)
We report the synthesis and X-ray crystal structure of 1,4-dihydro-2,6-dimethyl-4-(2'-isopropylphenyl)-3,5-pyridine-dicarboxy lic acid dimethyl ester (4), an analogue of the 1,4-dihydropyridine calcium channel antagonist, nifedipine. Solution state NOE data indicate the presence of both rotameric forms. The solid state shows exclusively one rotamer of 4 (that in which the 2'-isopropyl substituents is syn with C4H, which is also the major solution state rotamer). The 3,5-methyl esters adopt an ap/sp orientation with respect to the dihydropyridine double bonds in the solid state.
Transfer hydrogenation of aromatic and linear aldehydes catalyzed using Cp*Ir(pyridinesulfonamide)Cl complexes under base-free conditions
Townsend, Tanya M.,Kirby, Christopher,Ruff, Andrew,O'Connor, Abby R.
, p. 7 - 13 (2017/05/19)
Cp*Ir(pyridinesulfonamide)Cl (Cp*?=?pentamethylcyclopentadienyl) precatalysts 1–7 are active for the transfer hydrogenation of aryl, alkyl, and heterocyclic aldehydes. Catalysis is conducted under base-free conditions in air without dried or degassed substrates and solvents. These reductions occur rapidly in moderate to high conversion (39–100%). Benzaldehyde derivatives are reduced to alcohols within 30?min?at 85?°C using 1?mol% iridium precatalyst; reduction also occurs at lower temperatures and loadings (60?°C, 0.50?mol% precatalyst). Benzaldehyde derivatives that possess electron-rich and electron-poor substituents in the para position, including base-sensitive 4-hydroxybenzaldehyde, are readily reduced. Aryl aldehydes containing electron-poor groups are reduced faster than substrates possessing electron-rich moieties. Reduction of the positional isomers of methoxybenzaldehyde and isopropylbenzaldehyde shows highest reduction for the ortho isomer, followed by the meta isomer. Heterocyclic substrates, including biomass derived 5-hydroxymethylfurfural and 2-furfural, were reduced selectively to the alcohol. Decyl aldehyde was reduced to the linear alcohol; importantly self-condensation was not observed. Competition studies demonstrated selective reduction of aldehydes over ketones and a mercury poisoning experiment supports a homogeneous catalyzed pathway.
Nucleotides and nucleosides and methods for their use in DNA sequencing
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Page/Page column 134; 135, (2015/12/18)
The present invention relates generally to labeled and unlabled cleavable terminating groups and methods for DNA sequencing and other types of DNA analysis. More particularly, the invention relates in part to nucleotides and nucleosides with chemically cleavable, photocleavable, enzymatically cleavable, or non-photocleavable groups and methods for their use in DNA sequencing and its application in biomedical research.