摘要:

AbstractTriggleet al.[1] investigated a number of 4‐phenyl‐1,4‐dihydropyridines with respect to their X‐ray structure and the relation between a selection of six X‐ray variables and the calcium channel antagonist activity. We here extend their structure‐activity relation to include all fourteen X‐ray data given in ref. [1]. In addition, we develop an alternative QSAR based on a conventional physicochemical parametrization of the phenyl ring.A PLS model based on the physicochemical data separates active from inactive compounds, in contrast to the model based on the X‐ray data. Both PLS models with physicochemical data and with X‐ray data adequately predict the quantitative variation in activity for the

ISSN:0931-8771    

DOI:10.1002/qsar.19860050202

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

Abstract42 1,4‐naphthoquinones with substituents in the 2‐ and 3‐position were examined for their inhibitory activity on photosynthetic electron transport through photosystem II. The best ones were active in concentrations in the μM range or less. A QSAR was established, using the sum of the σ‐Hammett parameters and Taft's steric E csparameter for the substituents in the 2‐ and 3‐position. The QSAR could be improved, if instead of the E cs, the STERIMOL parameters L (for the 2‐position) and B3and B4(for the 3‐position) were applied. QSAR for different types of photosystem I1 inhibitors (urea, phenolic, quinoid) were compared. The differences in between them do support the idea of nonidentical though possibly overlapping binding sites at the reaction center comp

ISSN:0931-8771    

DOI:10.1002/qsar.19860050203

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractThe structural and electrostatic requirements for the two types of monoamine oxidase (MAO) activity are quantitatively studied using similarity coefficients between the electron density and the molecular electrostatic potential (MEP) distributions of a set of substrates.For the comparison of electron density distributions, the RXYsimilarity coefficient is used. In the case of MEP a new similarity coefficient is defined.Correlations between these coefficients and the experimental activities are studied and the results are consistent with previous ones. This shows the interest of this two parameters in QSAR studies.

ISSN:0931-8771    

DOI:10.1002/qsar.19860050204

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

摘要:

AbstractStudies were performed to determine if the screening of large pools of prospective variables could lead to fortuitous improvements in the classification success rates provided by nonparametric linear discriminants. These studies parallel earlier work by Topliss and Edwards on regression analysis. It was found that fortuitous increases do occur, but could probably be kept low if the number of examined variables is kept below one‐half the number of observation

ISSN:0931-8771    

DOI:10.1002/qsar.19860050205

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY

ISSN:0931-8771    

DOI:10.1002/qsar.19860050201

出版商:WILEY‐VCH Verlag    

年代:1986

数据来源: WILEY