Benzo perylene, synthesis

PAHs appear to affect other blood elements, as well. The influence of several PAHs on calcium ionophore-induced activation of isolated rabbit platelets was studied (Yamazaki et al. 1990). The activation of the platelets was assessed by measuring thromboxane 62 synthesis in response to stimulation by the calcium ionophore, A-23187. The authors reported that thromboxane 62 synthesis was inhibited by incubation of the stimulated platelets with benz[a]anthracene, chrysene, benzo[a]pyrene, and benzo[g,h,i]perylene, and stimulated by incubation with anthracene and pyrene. However, no statistical analysis was performed on these data, and the changes reported are generally within 10% of control values. In addition, the effects of the PAHs on thromboxane B2 synthesis are bidirectional, and in many instances, the same compound induced both inhibition and stimulation at different concentrations. 

Retention behavior was compared with a series of planar PAHs pyrene, benzo[ghi]perylene, coronene, benzo[pqr]naphtho[8,l,2-hcd]perylene, naph-tho[8,l,2-ahc]coronene, and ovalene (obtained from Aldrich or by synthesis). 

Reversed-phase EC on chemically bonded Cig (octadecylsilane) stationary phases is by far the most popular liquid chromatographic mode for separation of PAH compounds. Resolution is greatly influenced by the type of synthesis used to prepare the bonded phase. Good resolution can be achieved for the 16 US EPA PAHs on polymeric Cig phases. However, some isomers are unresolved (chrysene and benzo[a] anthracene) or only partially resolved [htmo ght perylene and indeno[l,2,3-cd]pyrene, benzo[ ]fluor-anthene, and benzo[ ]fluoranthene, or fluoranthene and acenaphthene) when monomeric Cig phases are used. 

Diels-Alder cycloaddition provides one of the most useful methods for the construction of polycyclic aromatic ring systems. With the use of maleic anhydride as dienophile, two additional carbon atoms may be fused to the bay region sites of some polycyclic arylenes to generate additional rings. For example, the first step in the synthesis of benzo[ghi]perylene 6 involves a Diels-Alder cycloaddition between perylene and maleic anhydride (Scheme 3.5) [19]. Aryne intermediates generated in situ also serve as dienophiles for Diels-Alder cycloadditions for example, reaction of 1,5-naphthadiyne (generated in situ from 2,6-dibromo-l,5-bis[(p-tolylsulfonyl)oxy] naphthalene with 2-methylisoindole forms an adduct which upon oxidation with m-chloroperbenzoic acid affords dibenzo[fe,k]chrysene 7 (Scheme 3.5) [20]. 

---