Contrastive relations

In spite of the attention focused on these bulky aryl substituents, especially in main-group chemistry, aryl ligands in which crowding is caused by the presence of ortho-aryl substituents formerly received little attention. In contrast, related terphenyl-substituted phenolate derivatives (e.g., -OC6H3-2,6-Ph2) of the early transition metals have been studied for many years, and zinc terphenolate derivatives have attracted attention (vide infra). A small number of similar aryl thiolate derivatives of transition metals (e.g., Mo, Fe, and Rh) have been characterized and published (vide infra). In addition, the related ligand -C6H2-2,4,6-Ph3 (Triph) had been employed as a ring substituent in bulky porphyrins.24... 

The alcohol-unsaturate couplings developed in our laboratory provide products of carbonyl addition. In contrast, related hydrogen auto-transfer processes provide products of alcohol substitution via pathways involving oxidation-condensation-reduction and the use of preactivated nucleophiles. For recent reviews, see [22-25]. 

Nallamothu BK, Shojania KG, Saint S, et al, Is acetylcysteine effective in preventing contrast-related nephropathy A metaanalysis. Am J Med 2004 I 17 938-947. 

The electronic nature of silylsilver intermediate was interrogated through inter-molecular competition experiments between substituted styrenes and the silylsilver intermediate (77).83 The product ratios from these experiments correlated well with the Hammett equation to provide a p value of —0.62 using op constants (Scheme 7.19). Woerpel and coworkers interpreted this p value to suggest that this silylsilver species is electrophilic. Smaller p values were obtained when the temperature of the intermolecular competition reactions was reduced [p = — 0.71 (8°C) and —0.79 (—8°C)]. From these experiments, the isokinetic temperature was estimated to be 129°C, which meant that the product-determining step of silver-catalyzed silylene transfer was under enthalpic control. In contrast, related intermolecular competition reactions under metal-free thermal conditions indicated the product-determining step of free silylene transfer to be under entropic control. The combination of the observed catalytically active silylsilver intermediate and the Hammett correlation data led Woerpel and colleagues to conclude that the silver functions to both decompose the sacrificial cyclohexene silacyclopropane as well as transfer the di-terf-butylsilylene to the olefin substrate. 

Stolz report that when a culture s system of spatial conception does not include the spatial opposition of right and left, contrastive relations are communicated with an up-down or front-back spatial metaphor instead. Interestingly, though the reference frame used in spatial metaphors may vary depending upon a given culture s system of spatial conception, the use of spatial reference frames for communicating opposition appears to be common across many cultures. 

When we decide to work with an EEE plan and when we have more than three factors, a new problem appears because we then have more possibilities to build the plan. Eor an answer to the question that requires a choice of most favourable possibility, we use the resolution power of each one of the options. So we generate the first possibility for an EEE plan by choosing the production (generation) relation. We can then go on with the contrast relation through which we obtain all the actual relations that are similar to those given in (5.107). 

In 50 patients (mean age 59 years) in an intensive care unit who underwent echocardiography examination with intravenous Optison (dose 0.5-1.5 ml), there were no contrast-related adverse effects (4). Good quality echocardiography was obtained in all cases. 

Bettmann MA.The evaluation of contrast-related renal failure (comment). AJR Am J Roentgenol 1991 157 66-68. 

We understand the molecular level properties of gases (either pure or mixed) at low pressures sufficiently well enough to make confident predictions of bulk properties. The relative simplicity of gases is due to the low cohesive energies between the molecules and between the molecules and container walls. In contrast, relating bulk properties to molecular properties in condensed phases (liquids and solids) becomes more complex, because of the greatly increased cohesive energies between the molecules. Nonetheless, the macroscopic properties of eondensed matter in the form of pure phases are now well understood from first principles. 

Kim J-J, Zhang Z, Park JC, Ng S-K (2006) BioContrasts extracting and exploiting protein-protein contrastive relations fi om biomedical literature. Bioinformatics 22 597-605... 

One of the most well-studied bimetallic catalysts used for the C-C coupling of alkynes are the thiolato-bridged diruthenium complexes 7 (Scheme 5) [22]. In the presence of NH4BF4 these complexes catalyse the head-to-head dimerisation of a number of terminal alkynes to selectively yield Z-enynes [23]. In contrast, related monometallic Ru catalysts typically yield a mixture of E- and Z-isomers, with the E-isomer more commonly favoured [24-26]. Previous work has shown that diruthenium complexes such as 7 are exceptionally robust due to the strong bridging ability of the thiolate ligands, which results in retention of the dinuclear core during reaction [27]. The proposed mechanism for the dimerisation reaction involves a concerted activation process where both Ru centres activate one alkyne each via the catalytic cycle shown in Scheme 5. Initial coordination of the first alkyne yields the vinylidene intermediate 8. The second alkyne then coordinates to... 

Palladium bis(dithiocarbamate) complexes derived from 4-(4 -alkyloxyphe-nylethyl)piperidines (434) display mesomorphic liquid-crystalline properties (1485), while in contrast, related complexes lacking the alkyl chains such as [Pd(S2CNC4HgNPh)2] and [Pd S2C N(CH2) Me 2 2] ( = 6,8) (1486) showed no mesomorphism as the chain length was not sufficiently long to depress the melting point enough (1486). 

Bis(dithiocarbamate) complexes, [M(S2CNC4HgX)2] (M = Pd, Pt X = O, S, CH2), have been tested for cyclostatic activity on KB cells, but show low activity at best (1585), as do a range of cationic amine complexes (1609). In contrast, related diamine complexes [M(diamine)(S2CNR2)][N03] (diamine = 2,2 -bpy, 1,10-phen) show antitumor activity against leucemic cells (1628,1629,1657). Further, administration of various dithiocarbamates at a low dose level with cisplatin has been found to afford almost complete protection against cisplatin induced renal toxicity and body weight loss without... 

The last columns gather the / (K)/ (E) contrasts related to both the EFISHG and HRS responses, a) There is no result for compounds 6 and 9 in the K forms since they are not stable. 

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