Info

Note: Exceptions to IUPAC rules are designated with asterisks.

6 Chen and Preston (1998).

Atkinson and Arey (1994) and references therein. h Lewtas and Nishioka (1990) and references therein. ' Zielinska et al. (1990) and references therein. ' Fraser et al. (1998). k Hannigan et al. (1998). 'Arey (1998a) and references therein.

m Tokiwa and Ohnishi (1986), Tokiwa et al. (1987), and references therein.

and basic) of extracts of ambient aerosols; the compounds included not only PAHs and aliphatics but also polar oxygenated substances, including several O-PACs and N-PACs. Similarly, Gundel and co-workers (1993) identified O-PACs and organic nitrates and nitrites as well as amides, amines, and nitro compounds in polar fractions of extracts of airborne particulate matter from particles (Dsa < 15 /Âżm) in ambient air in Elizabeth, New Jersey, and in the U.S. National Institute of Standards and Technology (NIST) Standard Reference Material SRM 1649, "Urban Dust/Organics" (see Box 10.3). Other investigators have identified S-PACs (e.g., dibenzothiophene) in the gas and particle phases of both direct emissions and ambient air.

Hence, some understanding of the nomenclature used for O-, N-, and S-PACs is also useful.

Given the presence of N-, O-, and S-heteroatoms as members of fused PAH ring systems (endocyclic), attached to such fused PAH rings (exocyclic), or both, the nomenclature of PACs is more complex than for PAHs. However, Chapter 2 of Polynuclear Aromatic Hydrocarbons—Nomenclature Guide by Loening et al. (1990) and Systematic Nomenclature of the Nitrogen, Oxygen, and Sulfur Functional Poly cyclic Aromatic Compounds (Later et al., 1990) provide a useful synopsis of the IUPAC rules for monofunctional N-, O-, and S-PACs (IUPAC, 1979). Many of the IUPAC rules for the parent, nonsubstituted PAHs described in Box 10.2 are applicable to these heteroatom derivatives. These rules are summarized in Box 10.4 (N-PAC), Box 10.5 (O-PAC), and Box 10.6 (S-PAC), respectively.

As an example, both replacement (aza) and substitutive (-N02) nomenclature are used in naming the powerful bacterial mutagen 3-nitro-6-azabenzo-

TABLE 10.4 Structures, Common Names, Empirical Formulas, and Molecular Weights for Selected Oxygen-Containing Polycyclic Aromatic Compounds (O-PACs) Identified in Ambient Air

Structure

Common name

Empirical formula

0 0

Post a comment