Stereospecific synthesis and (chir)optical redox properties of helicenoid-based phosphepine as well chiral P-containing polycyclic aromatic hydrocarbons are presented.

With the goal of eventually synthesizing [5]radialene (3), the still missing member of the parent radialene hydrocarbons, we have prepared the pentaacetates 21 and 31, the pentabromide 29 and the hexabromide 32. In principle these should be convertible by elimination reactions to the desired target molecule.

Measurements of the concentration of 3:4-benzpyrene and other polycyclic aromatic hydrocarbons have been made in gas works retort houses of several types. The tarry fumes which escaped from retorts contained extremely high concentrations of polycyclic hydrocarbons, but in general men were only exposed to these very briefly. The mean concentration of 3 :4-benzpyrene determined from long-period s...

High prevalences of idiopathic hepatic lesions were found in mummichog, Fundulus heteroclitus, from a site in the southern branch of the Elizabeth River, VA, contaminated with polycyclic aromatic hydrocarbons. Grossly visible hepatic lesions occurred in a total of 93% of the individuals from this site and 33% of these fish had hepatocellular carcinomas. Hepatic lesions were not detected in fish...

The new polycyclic borazines B(2){1,2-N(2)C(6)H(4)}(2){B(2)(NMe(2))(2)}(2), B(2){1,8-N(2)naph}(2){B(2)(NMe(2))(2)}(2) and B(2)(NPh)(4){B(2)(NMe(2))(2)}(2) have been prepared from diborate(4) anions and two equivalents of B(2)Cl(2)(NMe(2))(2) and have been structurally characterised. Aspects of their structure and bonding are discussed and comparison made with corresponding polycyclic aromatic h...