Fused rings, aromaticity

The fused 3+ ring aromatics in petroleum include both cata- and peri-condensed stmctures (see Table 4, Fig. 8). The cata-condensed species are those stmctures where only one face is shared between rings, the peri-condensed molecules are those that share more than one face. The fused ring aromatics form the class of compounds known as polynuclear aromatic hydrocarbons (PAH) which includes a number of recognized carcinogens in the 4+ ring family (33). Because of the potential health and environmental impact of PAH, these compounds have been studied extensively in petroleum. 

For the above reaction to occur, the aromatic nuclei in compound 1 should carry activating groups, such as hydroxyl, alkoxy, or fused ring aromatics". As a result of reaction with BF3 and phenol, the macromolecular structure of coal should undergo rupture at the aliphatic bridges, and these bridges are transferred to phenol molecules to produce bisphenols. Analysis of the bisphenols should provide information on the aliphatic bridges present in coal structure. 

A number of drugs have been successfully separated using MIPs. Naproxen , (S)-6-methoxy-a-methyl-2-naphthaleneacetic acid, is a nonsteroidal anti-inflammatory drug (NSAID) that is administered as the S enantiomer. Naproxen (structure 16.20) will be used to illustrate the MIP sequence. Naproxen has both polar and nonpolar domains. It also has a fused-ring aromatic site. 

Aust RB, Bentley WH, Drickamer HG (1964) Behavior of fused-ring aromatic hydrocarbons at very high pressure. J Chem Phys 41 1856-1864... 

Kosan Biosciences was formed almost 6 years ago, founded on an interest in polyketides, microbial metabolite-based drugs. Polyketides have many diverse chemical structures including erythromycin, which will be mentioned again later. These chemicals include fused-ring aromatic compounds, compounds decorated with sugars, and compounds with large stretches of double bonds. Each of these compounds has different biological activities and utilities, but they are all made in nature by very similar biochemistry. 

Fluoranthene (Called 1,2-benzo-acenaphthy-len or 1,8-o-phenylen-naphthylen in Ger), C16H10(Thought to be ClaH10in early literature), mw 202.24, colorless ndls, sp gr 1.158 at 20°, nD 1.739 at 20°, bp 393°, 217°(30mm Hg), mp 109.5-110.5°, sol In benz, chlf, eth, HAc hot ale. A tetracyclic fused ring aromatic hydrocarbon, this material is found in some coal tars. It forms definite complexes with many poly nitrated aromatics (Refs 1 to 6) Refs 1) Beil 5, 685, (340, 344), [609] 2276 2) J. vonBraun E. Anton, Ber... 

Figure 2. Variation in the normalized hydrocarbon product distribution with time on stream in the conversion of C2H2 (WHSV = 0.48 hr1) over pure H-ZSM-5 at 400 °C. Figure shows both total aromatic and, separately, fused-ring aromatic component of total aromatics.

A. Gavezzotti, G. R. Desiraju, A Systematic Analysis of Packing Energies and other Packing Parameters for Fused-Ring Aromatic Hydrocarbons. Acta Crystallogr. B 1988, 44, 427-434. 

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