the nitrite ® nitro isomerization in nitritopentaamine cobalt (iii) halides has been known. in this paper, the effect of the size of the counter ions (noncoordinated groups) on the rate of isomerization in nitritopentaamine cobalt (iii) halides, is reported. the rate of isomerization is decreased by increasing the size of the counter ions. this decrease is explained on the basis of steric inter...

Ruthenium complexes with tetradentate PNNP donor ligands demonstrate a marked change in selectivity compared to analogous bis bidentate PN Guerbet catalysis, producing mixtures of n-butanol (17 %), sec-butanol (14 %) and ethyl acetate (66 rather than the usual 90 %+ n-butanol. Tridentate PNP ruthenium such as [Ru(H)(Cl)(CO)(Ph2PCH2CH2NHCH2CH2PPh2)] also produce and, optimized conditions (120 °C...

An unsaturated fatty acid auxotroph of Escherichia coli was grown with a series of cis-octadecenoate isomers in which the location of the double bond varied from positions 3 to 17. Each of these fatty acid isomers was incorporated into the cellular lipids, but cyclopropane derivatives were formed to at least a 3-fold greater extent from the cis-9 and cis-11 isomers than from any other positiona...

Abstract Conventional hydrofunctionalization of ?-olefins with mineral acids proceeds Markovnikov selectivity to afford branched isomers. The direct formation linear constitutional isomers is challenging, yet anti-Markovnikov addition would be valuable for the synthesis commodity chemicals, such as primary alcohols, which are currently only accessible via stoichiometric redox reactions, a full ...

in this paper, absorption spectra of both solution and films of cyano azobenzene polymer are investigated. the analysis of overlapped absorption spectra of polymer, related to trans and cis isomers, shows that the population of cis isomers is higher than trans isomers. it means that, cyano azobenzene molecules have a folded structure in polymer, in thermal equilibrium. presence of cyano molecul...

New racemic and chiral methyl 2-{[4-(4-chlorophenyl)-4-hydroxypiperidin-1-yl]methyl}-1-phenylcyclopropanecarboxylate derivatives were synthesized in order to obtain sigma ligands with increased affinity and selectivity compared to (+)-MPCB and haloperidol. The cis-(±)-7 racemic mixture showed a better binding affinity and selectivity than the (±)-8 trans isomers. Between the two cis enantiomers...

A small library of 1,5-triazole derivatives linking a diaminocyclopentadiol and aromatic ketones has been prepared and screened using NMR and fluorescent techniques against tRNA(Lys)(3), the HIV reverse transcription primer. The comparison of their binding properties to those of their 1,4-triazole isomers, previously discovered in a fragment-based approach, outlines the influence of the linker ...

3-Iodo-4-(2'-methylcyclohexyloxy)-6-phenethylpyridin-2(1H)-ones, as effective non-nucleoside reverse transcriptase inhibitors, were synthesized and resolved with different configurations. Biological results revealed that the trans-racemate 2b exhibited more potent activity than the cis-isomers. Noticeably, the trans-(S,S)-enantiomer 2e turned out to be significantly more potent than its counter...

A small library of Fmoc-protected 3-arylated tyrosines was created by radical arylation. The new building blocks were successfully applied in the synthesis of two novel neurotensin receptor ligands. Both isomers showed high affinity for the human NTS2 receptor with K(i) values in the nanomolar range. Interestingly, subtype selectivity strongly depends on the configuration of the peptide in posi...