Pyrene derivative

The pyrene derivative (17) [3271-22-5] is obtainable by the Friedel-Crafts reaction of pyrene with 2,4-dimethoxy-6-chloro-j -triazine, and is used for brightening polyester fibers (75). 

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. 

In general and as expected, brighteners of relatively small molecular size are most suitable for application by exhaustion. Less volatile compounds of larger molecular size tend to be preferred for pad-thermosol application or for incorporation in the polymer mass. Commercially important for exhaust application are the previously mentioned pyrene derivative 11.22, the naphthalimide 11.23, the bis(benzoxazolyl)ethene 11.35, the bis (benzoxazolyl) thiophene 11.36, the distyrylbenzene 11.37 and the stilbene bis (acrylic ester) derivative 11.38. Products of the 11.35 type show excellent light fastness but only moderate fastness to sublimation. In view of this volatility they can be used in the transfer printing of polyester. 

Table 2 Coal liquefaction by pyrene derivatives (reaction temp.=370°C, solvent/coal=3/l)...

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

DNA and RNA quantification, SNP typing, hybridization, and structural alteration have been widely carried out by modified oligonucleotides possessing pyrene derivatives [104-113]. As is known, pyrene-1-carboxaldehyde fluorescence is considerably dependent on solvent polarity [114], being strong in methanol but insignificant in nonpolar solvents [115]. Owing to this property, Tanaka and collaborators developed a pyrenecarboxamide-tethered modified DNA base, PyU 46, and applied it to SNP discrimination in DNA [116-120],... 

Maehashi et al. (2007) used pyrene adsorption to make carbon nanotubes labeled with DNA aptamers and incorporated them into a field effect transistor constructed to produce a label-free biosensor. The biosensor could measure the concentration of IgE in samples down to 250 pM, as the antibody molecules bound to the aptamers on the nanotubes. Felekis and Tagmatarchis (2005) used a positively charged pyrene compound to prepare water-soluble SWNTs and then electrostatically adsorb porphyrin rings to study electron transfer interactions. Pyrene derivatives also have been used successfully to add a chromophore to carbon nanotubes using covalent coupling to an oxidized SWNT (Alvaro et al., 2004). In this case, the pyrene ring structure was not used to adsorb directly to the nanotube surface, but a side-chain functional group was used to link it covalently to modified SWNTs. 

Caution Many pyrene derivatives are carcinogens. Contact of the skin with these materials should be avoided. 

The primary focus of the study by Guthrie and Pfaender [360] was to assess how biological activity influenced interactions of pyrene and pyrene derivatives with soil organic matter, by determining how microbial activity influenced associations between pyrene and particular SOM fractions over extended periods of time. Experiments were then conducted to determine if pyrene-SOM associations altered the pyrene bioavailability, and designed to... 

Fig. 3.14 Schematic representation of noncovalent interaction (/.e., n-stacking) between the CNT surface and a pyrene derivative for protein functionalization. Adapted with permission from [74], 2009, American Chemical Society.

The most common linker molecules are pyrene derivatives, which have been used, for example, to link Au [64,65] and Pd [66] NPs, as well as QDs [67] to CNTs. Martin et al. chemically attached a n-extended tetrathiafulvalene (exTFF) group to pyrene prior to n-n hybridization on SWCNTs in order to investigate donor-acceptor interactions between the SWCNT and electron rich exTFF [68], More recently, the same group has synthesized a complex molecule consisting of two exTFF anchors connected via a flexible linkage that also consists of a second generation carboxylic terminated den-dron [69]. Here, n interactions between the exTFF anchors and the SWCNTs lead to hybridization while the carboxylic acid groups of the dendron (when de-protonated) lead to increased solubility in aqueous solutions [69]. 

Alternatively, benzyl and pyrene derivatives offer a noncovalent approach to alter nanocarbon surface chemistry and have been studied extensively [62]. For example,... 

Members of another class of powerful direct mutagens, four nitroazabenzo[a]pyrene derivatives, were identified by Sera and co-workers (1994) in the basic fraction of extracts of diesel exhaust and in ambient POM. Structures and direct mutagenic activities on strains TA98 and YG1024 (-S9 mix) of the 1- and 3-nitro-6-azabenzo[a]pyrenes and the 1- and 3-nitro-6-azabenzo[a]pyrene-7V-oxides are shown in Table 10.21 (Sera et al., 1992 Fukuhara et al., 1992). They have been measured in ambient air in Fukuoka, Japan, at concentrations of 1.1, 1.2, 0.8, and 0.3 ng/g, respec-... 

Sera, N., K. Fukuhara, N. Miata, and FI. Tokiwa, Detection of Nitro-azabenzo[ ]pyrene Derivatives in the Semi-volatile Phase Originating from Airborne Particulate Matter, Diesel and Gasoline Vehicles, Mutagenesis, 9, 47-52 (1994). 

Benzylic-type cations derived from PAHs have been studied under superacid conditions, where, not surprisingly, they are relatively stable.Lifetimes in water of diastereomeric forms of the benzo[a]pyrene derivative (100) have been deter-... 

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... 

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