0000000000255742
AUTHOR
G.m. Antón-fos
Molecular connectivity as a relevant new tool for predicting analytical behavior: A survey of chemiluminescence and chromatography
Abstract We present a critical presentation and discussion on molecular connectivity applied to analytical fields, giving special attention to predicting the chemiluminescent behavior of pharmaceuticals and pesticides. Molecular connectivity has been largely applied to predict the therapeutic effects of pharmaceuticals and rarely to predictions in analytical chemistry – basically to chromatographic processes and recently to liquid-phase chemiluminescence.
Theoretical prediction of the photoinduced chemiluminescence of pesticides
Although it is relatively easy to find chemiluminescent (CL) molecules working on the field of direct liquid phase (especially employing strong oxidants), the molecules found as chemiluminescent are normally very weak CL compounds for developing suitable analytical CL-procedures. Therefore, it is mandatory to develop new strategies to enhance in a simple way the native chemiluminescence of such a compounds, and even to increase the number of compounds to be determined by direct chemiluminescence. Photoinduced chemiluminescence (Ph-CL) results in a simple and easily on-line accessible strategy to solve these disadvantages. In the present paper, molecular connectivity, a topological method wh…
Search of a topological pattern to evaluate toxicity of heterogeneous compounds.
Abstract Molecular connectivity has been applied to the search of mathematical models able to predict the carcinogenic and teratogenic activity of a wide group of structurally heterogeneous compounds. Through the linear discriminant analysis and the diagrams of distribution of pharmacological activity, the classification criteria that minimizes the percentage of error are established. The easiness and speed of the calculation of the descriptors used in this work make the models developed useful in data bases containing a huge number of compounds.
Theoretical prediction of the native fluorescence of pharmaceuticals
At present, to search fluorescent compounds or to increase the native fluorescence is an active research line specially and not only with analytical purposes. On some analytical areas and from the early times of applications of fluorescence (mid-fifties) the fluorimeter was defined as the suitable detector for determination of pharmaceuticals and subsequently, this detection mode has been widely applied. Therefore, it is mandatory to develop new strategies to discover or to enhance in a simple way the native fluorescence of organic compounds to increase the number of analytes to be determined by direct fluorescence. In the present paper are studied further applications of a new tool suitabl…
Search for New Antihistaminic Compounds by Molecular Connectivity
In this paper it is demonstrated that by adequate selection of topological descriptors we can make possible the prediction of different pharmacological properties, such as plasmatic concentration or sedative effect, within a group of antihistaminic drugs. Moreover, also demonstrated is the usefulness of molecular connectivity in the search of new active compounds. Examples of such compounds are 4-(l-buthylpenthyl)pyridine, N-(3-bromopropyl)-phtalimide and N-(3-chlorpropyl)-piperidin hydrochloride. All of them show antihistaminic activity values more than 30% higher than that of terfenadine, which is used as the reference drug.
Search compounds with antimicrobial activity by applying molecular topology to selected quinolones.
Molecular topology was used to obtain substances with antimicrobial activity. Selected quinolones were employed to develop the corresponding connectivity functions and discriminant equation. Limiting functions were selected that allowed the discriminant function to more efficiently distinguish substances with and without antibacterial activity. Antibacterial tests were run to confirm the theoretically established activity.
Calculation of chromatographic parameters by molecular topology: sulphamides
This investigation was undertaken to test the ability of the molecular connectivity model to predict RF values in thin-layer chromatography (TLC) for a group of sulphamides using multi-variable regression equations with multiple correlation coefficients, standard error of estimate, F-Snedecor function values and Student's t-test as criteria of fit. Regression analyses showed that the molecular connectivity model predicts the values for this property in different silica gel stationary phases and different polar mobile phases. Corresponding stability and random studies were made on the selected prediction models which confirmed their goodness of fit. The results also demonstrated that differe…
New hypoglycaemic agents selected by molecular topology.
Abstract New compounds showing hypoglycaemic activity have been designed through a computer aided method based on quantitative structure–activity relationship (QSAR) and molecular connectivity. After calculation of topological indices for a set of 89 compounds including active and inactive with regards to hypoglycaemic action, linear discriminant analysis was performed so that a useful model to predict such an activity was achieved. Later on, the discriminant model was applied on a huge database so that fourteen compounds were selected as potential new hypoglycaemics. From them, just five were finally selected for experimental test on expected hypoglycaemic activity. Among the selected comp…
Pharmacological studies of 1-(p-chlorophenyl)propanol and 2-(1-hydroxy-3-butenyl)phenol: Two new non-narcotic analgesics designed by molecular connectivity
Abstract Molecular topology has been applied to the design of new analgesic drugs. Linear discriminant analysis and connectivity functions were used to design two potentially suitable drugs which were synthesized and tested for analgesic properties by the acetic acid-induced abdominal constriction test in mice and the tail-flick test in rats. In mice, the compound 1-(p-chlorophenyl)propanol showed higher analgesic activity, both intraperitoneally and orally, than acetylsalicylic acid. 2-(1-Hydroxy-3-butenyl)phenol exhibited a lesser protective effect (70% of that shown by acetylsalicylic acid). In rats, acetylsalicylic acid gave the greatest protection against pain when administered intrape…
Use of molecular topology for the prediction of physico-chemical, pharmacokinetic and toxicological properties of a group of antihistaminic drugs
We used molecular connectivity to search mathematical models for predicting physico-chemical (e.g. the partition coefficient, P), pharmacokinetic (e.g. the time of maximum plasma level, and toxicological properties (lethal dose, LD) for a group of antihistaminic drugs. The results obtained clearly reveal the high efficiency of molecular topology for the prediction of these properties. Randomization and cross-validation by use of leave-one-out tests were also performed in order to assess the stability and the prediction ability of the connectivity functions selected.