Application of topological properties and graph theory to benzenoid hydrocarbons allowed us to construct an effective approach interpreting ring current formation in molecules when exposed to an external magnetic field. Transformation of unexcited canonical structures for molecules of 34 benzenoid hydrocarbons into circuit structures and then to directed circuit structures allowed us to define ...

The local aromaticity of a series of benzenoid systems was determined through the use of structurally (HOMA) and magnetically (NICS) based measures, and also by using a new electronically based indicator of aromaticity, the para-delocalization index (PDI). The results were compared with the predictions of Clar’s aromatic -sextet rule. It is found that, for all analyzed benzenoid hydrocarbons ha...

Biosynthesis of benzoic acid from Phe requires shortening of the side chain by two carbons, which can occur via the β-oxidative or nonoxidative pathways. The first step in the β-oxidative pathway is cinnamoyl-CoA formation, likely catalyzed by a member of the 4-coumarate:CoA ligase (4CL) family that converts a range of trans-cinnamic acid derivatives into the corresponding CoA thioesters. Using...

A new parameter, related to and easily determined from the structure of a benzenoid system and that of a phenylene – the number of inlets (r) – is introduced. The connectivity (Randi}) index of both benzenoid systems and phenylenes is then shown to depend solely on the number of vertices and on r. A simple relation is established between the connectivity index of a phenylene and of the correspo...

Floral volatile benzenoid/phenylpropanoid (FVBP) biosynthesis is a complex and coordinate cellular process executed by petal limb cells of a Petunia×hybrida cv. 'Mitchell Diploid' (MD) plant. In MD flowers, the majority of benzenoid volatile compounds are derived from a core phenylpropanoid pathway intermediate by a coenzyme A (CoA) dependent, β-oxidative scheme. Metabolic flux analysis, revers...

The enumeration of Kekule structures has fasci­ nated several researchers since the first systematic studies of benzenoids in terms of graph theory [1-9] , Apart from the recognized importance of Kekule structures in organic and physical chemistry they also have purely mathematical interest. Refer­ ence is made to a recent article in the present jo u r ­ nal [10] along with the bibliography the...

It is shown that the vertices of benzenoid systems admit a labeling which reflects their distance relations. To every vertex of a molecular graph of a benzenoid hydrocarbon a sequence of zeros and ones (a binary number) can be associated, such that the number of positions in which these sequences differ is equal to the graph-theoretic vertex distance. It is shown by an example that such labelin...