Aromatic pyrene derivatives

Coman et al. [82] used a new modeling of the chromatographic separation process of some polar (hydroxy benzo[a]pyrene derivatives) and nonpolar (benzo[a]pyrene, dibenz[a,/ ]anthracene, and chrysene) polycyclic aromatic compounds in the form of third-degree functions. For the selection of the optimum composition of the benzene-acetone-water mobile phase used in the separation of eight polycyclic aromatic compounds on RP-TLC layers, some computer programs in the GW-BASIC language were written. 

Polycyclic aromatic compounds, namely naphthalene, anthracene and pyrene derivatives are widely used as fluorescent probes in relevant biomolecules. 

Excimer formation can serve as a sensitive probe of group proximities Excimers make evident the interaction of an excited molecule M, (typically an aromatic hydrocarbon), with a molecule in the ground state M producing an excited dimer Mf (or D ). The dimer must be formed within the lifetime of the excited species (e.g., for pyrene derivatives, about 100 nsec). For molecules such as pyrene, excimer formation and fluorescence are contingent on attainment of a well-defined steric arrangement in the dimer.41... 

Reaction of naphthalene, anthracene and pyrene derivatives with trifluoromethyl hypofluorite at — 78 C results mainly in fluoro-substituted products 36 and difluoro ketones 37. The ratio between the two types of products depends on the substituents and the structure of the aromatic molecule.58-61... 

Abstract Pressure-sensitive paint (PSP) is applied to the areodynamics measurement. PSP is optical sensor based on the luminescence of dye probe molecules quenching by oxygen gas. Many PSPs are composed of probe dye molecules, such as polycyclic aromatic hydrocarbons (pyrene, pyrene derivative etc.), transition metal complexes (ruthenium(II), osumium(II), iridium(III) etc.), and metalloporphyrins (platinum (II), palladium(II), etc.) immobilized in oxygen permeable polymer (silicone, polystyrene, fluorinated polymer, cellulose derivative, etc.) film. Dye probe molecules adsorbed layer based PSPs such as pyrene derivative and porphyrins directly adsorbed onto anodic oxidised aluminium plat substrate also developed. In this section the properties of various oxygen permeable polymer for matrix and various dye probes for PSP are described. 

Polycyclic aromatic hydrocarbons (PAH s) with external cyclopentafused five-membered rings, such as the cyclopentafused pyrene derivatives (Fig. 10), belong to the class of non-alternant polycyclic aromatic hydrocarbons. 

The usual configuration of LNA is p-o-ribose, but other configurations of LNA have been examined. cx-d-LNA and p-L-LNA nucleosides have very high affinity with complementary RNA in a parallel-stranded duplex. Aryl C-nucleosides in the a-L-configuration cf 52, base=aromatic residue) demonstrate preferential binding to DNA, with a pyrene derivative showing highest affinity and, as with the p-o-derivative it behaves as a universal base. ... 

Other examples of generating free radicals utilized in our laboratory are the consecutive two-photon ionization of the aromatic pyrene residue in the benzo[a] pyrene derivative 7,8,9,10-tetrahydroxytetrahydrobenzo[a]pyrene (B[a]PT) or the covalent adducts derived from the reactions of racemic anti-r7,t8-dihydroxy-t9,10-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (B[a]PDE) with the N2-exocyclic amino groups of guanine or adenine bases in DNA [43-47]. The selective excitation of the pyrenyl residue of B[a]PT by intense 355-nm nanosecond laser pulses yields free radical products by a two-photon mechanism ... 

The selectivity in the non-covalent functionalization of metallic v. semiconducting SWNTs is apparently dependent on the specific planar aromatic molecule, positive for one pyrene derivative (1-docosyloxymethyl-pyrene or... 

Pyrene (Fig. 14.17) is also aromatic. Pyrene itself has been known for a long time a pyrene derivative, however, has been the object of research that shows another interesting... 

The strategy of using functional pyrene derivatives is commonly employed when interfacing graphene with biological systems. However, besides pyrene [133,134], pentacene [135], dopamine [136], and some other aromatic derivatives were also used [137-139]. By functionalizing graphene with different chemical compounds, it can be endowed with the desired properties. 

A number of aromatic hydrocarbon derivatives have been used as fluorophores, but probably the most widely used analogue is pyrene. Pyrene exhibits a strong fluorescent emission band, but when paired with another fluorophore, such as pyrene itself, it exhibits excimer fluorescence. Various applications have indeed used this monomer to dimer fluorescence... 

Besides aromatic hydrocarbons such as pyrene (above), benzanthracene (Becker et al., 1977a), benzoin derivatives (Baumann et al., 1982), aromatic and heteroaromatic ketones (Fomin et al., 1980 Baumann et al., 1985), azo dyes (Timpe et al., 1982), methylene blue (Becker et al., 1986 a Becker and Kohrs, 1990), acridine yellow... 

Methods for the synthesis of the biologically active dihydrodiol and diol epoxide metabolites of both carcinogenic and noncarcinogenic polycyclic aromatic hydrocarbons are reviewed. Four general synthetic routes to the trans-dihydrodiol precursors of the bay region anti and syn diol epoxide derivatives have been developed. Syntheses of the oxidized metabolites of the following hydrocarbons via these methods are described benzo(a)pyrene, benz(a)anthracene, benzo-(e)pyrene, dibenz(a,h)anthracene, triphenylene, phen-anthrene, anthracene, chrysene, benzo(c)phenanthrene, dibenzo(a,i)pyrene, dibenzo(a,h)pyrene, 7-methyl-benz(a)anthracene, 7,12-dimethylbenz(a)anthracene, 3-methylcholanthrene, 5-methylchrysene, fluoranthene, benzo(b)fluoranthene, benzo(j)fluoranthene, benzo(k)-fluoranthene, and dibenzo(a,e)fluoranthene. 

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