Ligand disorder

Avila et al., 2004). A quadratic temperature dependence of the resistivity was found below 1.5 K, which is a characteristic feature of strong electron correlation (Yatskar et al., 1996). Figure 49 shows that the resistivity-vs.-temperature curves can be drastically modified by annealing the YbNi2E>2C samples, which has been explained by ligand disorder leading to local distributions of Tk (Avila et al., 2004). 

Table 6.2 Mononuclear transition metal-hydrogen complexes in solid state metal hydrides as of May 2007 ou = average due to ligand disorder...

Dichloro(propene) (/i,/ )-AW -dimethyl-MV -bis(a-methylbenzyl)-l,2-ethanediamme platinum (n) Pt, M5/> )2 2.148(29), trigonal bipyramidal, propene ligand disordered Benzophenonedilithium tetrahydrofuran tetramethylethylenediamine Li, 2.244— 2.578,... 

Melatonin [73-31-4] C 2H N202 (31) has marked effects on circadian rhythm (11). Novel ligands for melatonin receptors such as (32) (12), C2yH2gN202, have affinities in the range of 10 Af, and have potential use as therapeutic agents in the treatment of the sleep disorders associated with jet lag. Such agents may also be usehil in the treatment of seasonal affective disorder (SAD), the depression associated with the winter months. Histamine (see Histamine and histamine antagonists), adenosine (see Nucleic acids), and neuropeptides such as corticotropin-like intermediate lobe peptide (CLIP) and vasoactive intestinal polypeptide (VIP) have also been reported to have sedative—hypnotic activities (7). 

Crystal stmcture data are available for an indole—trinitroben2ene complex (2) and for the lithium and sodium salts in the presence of polyamine Ligands (3). The crystal stmcture of indole itself is evidendy disordered (4). Table 1 gives the and C-nmr assignments in CDCl (5). C-nmr assignments have been tabulated for many other indole derivatives (6). 

In addition to those described above, some of the newest compounds emerging in SERM development are ER 3-selective ligands and pathway-selective modulators that target the interaction of the ERs with the transcription factor NFkB. While such compounds are in the early stages of clinical evaluation, thus far they demonstrate great potential for use in the treatment of inflammatory disorders such as arthritis, inflammatory bowel disease, and like other SERMs, cancer [4]. 

The undisputed efficacy of benzodiazepines in relief of anxiety led to the question of whether this disorder could arise from abnormal concentrations in the brain of an endogenous ligand or a malfunction of the benzodiazepine/GABA receptor system. An important study, aimed at distinguishing between these possibilities, has been carried out in humans (Nutt et al. 1990) and was based on the premise that anxiety could be caused by either ... 

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