Heteroaromatic compounds acid—base properties

Belenkii has reviewed the effect of acid-base properties of heteroaromatic compounds on their electrophilic substitution reactions (86CHE587). 

We established [54] that, in conjunction with 2D-based descriptors, ChemGPS can provide global chemical space coordinates by performing extensive comparisons with GRID-based principal properties for heteroaromatic compounds [59], principal properties ( z-scores ) of a-amino acids [60], as well as by comparison to several local PCA models. The initial ChemGPS map turned out to be 9-dimensional [54]. 

Electrophilic substitution of heteroaromatic compounds, effect of their acid-base properties on 86KGS749. 

The study of the reactivity of the nucleic acid bases utilizes indices based on the knowledge of the molecular electronic structure. There are two possible approaches to the prediction of the chemical properties of a molecule, the isolated and reacting-molecule models (or static and dynamic ones, respectively). Frequently, at least in the older publications, the chemical reactivity indices for heteroaromatic compounds were calculated in the -electron approximation, but in principle there is no difficulty to define similar quantities in the all-valence or allelectron methods. The subject is a very broad one, and we shall here mention only a new approach to chemical reactivity based on non-empirical calculations, namely the so-called molecular isopotential maps. 

Abstract Mixed-quantum classical dynamics simulations have recently become an important tool for investigations of time-dependent properties of electronically excited molecules, including non-adiabatic effects occurring during internal conversion processes. The high computational costs involved in such simulations have often led to simulation of model compounds instead of the full biochemical system. This chapter reviews recent dynamics results obtained for models of three classes of biologically relevant systems protonated Schiff base chains as models for the chromophore of rhodopsin proteins nucleobases and heteroaromatic rings as models for UV-excited nucleic acids and formamide as a model for photoexcited peptide bonds. 

---