Anthraquinones complexes

Similarly, the hydride reduction of the fluorenone and anthraquinone complexes gives the corresponding secondary alcohols with endo-OH groups resulting from stereospecific attack [134], This strategy is also known in the Cr(CO)3(arene)... 

Additional studies using the same complexes in both cisplatin sensitive and resistant forms of U2-OS cells also showed differences in the cellular processing of the drugs both the free ligands and platinum complexes were rapidly found to accumulate in the nucleus, after uptake into the Golgi, which was hypothesized to be involved in transport of the platinum complexes out of the cells (56). In this set of studies, fluorescence imaging helped to illustrate the differences in the intracellular interactions of dinuclear platinum-anthraquinone complexes in different cell lines and in the different resistance profiles of A2780 and U2-OS resistant sub lines. 

In a separate fluorescence microscopy smdy, the distribution of a mononuclear neutral platinum-anthraquinone complex, Pt-1 C3 (1), was examined in human colon adenocarcinoma cells... 

Table 3.4 Redox Potentials of Ferrocene-Anthraquinone Complexes and Their Protonated Species in 0.1 mol dm Bu4NC104-CH2Cl2 ...

Reaction with additional alkyne releases an organic anthraquinone (128). Numerous TT-complexes are known. Examples include complexes of alkenes,... 

Ring closure of o-benzoylbenzoic acid to anthraquinone is an unusual reaction in that normally it is not predicted to occur ortho to a keto group. Several theories have been proposed to explain the mechanism whereby this could possibly occur. One involves a complex ionization of o-benzoylbenzoic acid (41), the other favors the intermediate formation of 3-hydroxy-3-phenyl-l(3JT)isobenzofuranone (9) [64693-03-4] and 3-phenylphthaHdyl sulfate (10) (42) ... 

Mechanism of Anthraquinone Acceleration. The mechanism for the dual function of AQ has been the subject of much research (29). Anthraquinone is an effective pulping accelerator in very small quantities and functions as a catalyst in the process. It is generally accepted that AQ functions in a complex redox sequence. 

The vapor-phase oxidation (VPO) of butadiene with air at 200—500°C produces maleic anhydride [108-31-6]. Catalysts used are based on vanadium and molybdenum oxides (89,90). Alternatively, when using a catalyst containing Al, Mo, and Ti, butadiene undergoes a complex series of condensations and oxidations to form anthraquinone at 250°C (91). 

Anthraquinone dyes have been produced for many decades and have covered a wide range of dye classes. In spite of the complexity of production and relatively high costs, they have played an important role in the areas where excellent properties ate requited, because they have excellent lightfastness and leveling properties with brUhant shades that ate not attainable with other chtomophotes. However, recent increases in environmental costs have become a serious problem, and future prospects for the anthraquinone dye industry ate not optimistic. Some traditional manufacturers have stopped the production of a certain dye class or dye intermediates that were especially burdened by environmental costs, eg, vat dyes and their intermediates derived from anthraquinone-l-sulfonic acid and 1,5-disulfonic acid. However, several manufacturers have succeeded in process improvement and continue production, even expanding their capacity. In the forthcoming century the woddwide framework of production will change drastically. 

Anthraquinone, 1-hydroxy-calcium aluminum chelate compound, 1,2 metal complexes dyes, 6,86 Antiarthritis drugs labelled gold compounds, 6, 969 metal complexes, 6,758 Antibiotic M139163,2, 974 Antibiotics ionophoric, 6, 553 metal complexes selective binding, 6, 552... 

The syntheses of three polycyclic anthraquinones, indanthrone (53), pyranthrone (55a) and flavanthrone (55b), are illustrated in Scheme 4.7. In spite of the structural complexity of the products, the syntheses of these types of compound are often quite straightforward, involving, for... 

Oxidative repair is not a unique feature of our Rh(III) complexes. We also demonstrated efficient long-range repair using a covalently tethered naphthalene diimide intercalator (li /0 1.9 V vs NHE) [151]. An intercalated ethidium derivative was ineffective at dimer repair, consistent with the fact that the reduction potential of Et is significantly below the potential of the dimer. Thymine dimer repair by a series of anthraquinone derivatives was also evaluated [151]. Despite the fact that the excited triplets are of sufficient potential to oxidize the thymine dimer ( 3 -/0 1.9 V vs NHE), the anthraquinone derivatives were unable to effect repair [152]. We attribute the lack of repair by these anthraquinone derivatives to their particularly short-lived singlet states anthraquinone derivatives that do not rapidly interconvert to the excited triplet state are indeed effective at thymine dimer repair [151]. These observations suggest that interaction of the dimer with the singlet state may be essential for repair. 

J. Sanyova and J. Reisse, Development of a mild method for the extraction of anthraquinones from their aluminum complexes in madder lakes prior to HPLC analysis, J. Cult. Herit., 7,... 

Note that the charge-transfer irradiation of the same anthracene/Os04 complex in hexane solution yields only a small amount of the adduct (B) together with considerable amounts of anthraquinone. The latter probably arises from osmylation at the (9,10) positions followed by decomposition of the unstable osmium adduct.218... 

See also Disazo mordant dyes anthraquinone, 9 337 dyeing procedures, 9 399 metal complexes of, 9 394-399 soluble, 7 373t Mordenites... 

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