The structure of epothilone A, bound to , -tubulin in zinc-stabilized sheets, was determined by a combination of electron crystallography at 2.89 angstrom resolution and nuclear magnetic resonance–based conformational analysis. The complex explains both the broad-based epothilone structureactivity relationship and the known mutational resistance profile. Comparison with Taxol shows that the lon...

94. Van Quaquebeke, E.; Simon, G.; Andr, A.; Dewelle, J.; El Yazidi, M.; Bruyneel, F.; Tuti, J.; Nacoulma, O.; Guissou, P.; Decaestecker, C.; Braekman, J.C.; Kiss, R.; Darro, F. Id entification of a novel cardenolide (2''-oxovoruscharin) from Calotropis procera and the hemisynthesis of novel derivatives displaying potent in vitro antitumor activities and high in vivo tolerance: structureactivit...

Topological indices play an important role in Mathematical Chemistry especially in the quantitative structure-property relationship (QSPR) and quantitative structureactivity relationship (QSAR). Recent research indicates that the augmented Zagreb index (AZI) possess the best correlating ability among several topological indices. The main purpose of the current study is to establish some mathema...

Small-conductance (KCa2) and intermediate-conductance (KCa3.1) calcium-activated K channels are voltage-independent and share a common calcium/calmodulin-mediated gating mechanism. Existing positive gating modulators like EBIO, NS309, or SKA-31 activate both KCa2 and KCa3.1 channels with similar potency or, as in the case of CyPPA and NS13001, selectively activate KCa2.2 and KCa2.3 channels. We...

Establishing relationships between the chemical structures and their activities or properties are crucial to achieve a goal, doing better and fewer experiments. The quantitative description of the relations is the so-called quantitative structureactivity/property relationships (QSAR and QSPR) [Gedeck et al. 2008, Yap et al. 2007]. QSAR studies express the biological activity of compounds as a f...

A new approach for analyzing the moleculedescriptor matrix for the QSAR problem (Quantitative StructureActivity Relationship) based on a fuzzy cluster structure of the learning sample is presented. The ways for generating fast rules for refusing prediction and searching the spikes in the learning sample are described. For this purpose, a special space of descriptors, simple for calculation, is ...

We tackle the problem of automatic detection of StructureActivity relationships by means of Inductive Logic Programming (ILP). We describe an algorithm for constructing features from background knowledge (stochastic propositionalization SP) and an abstract level representation for chemical compounds.

enzymatically prepared by removing acyl moieties from the cyclohexane ring of LSNs, and its thrombopoietic effects. Furthermorewealso report on the structureactivity relationship of its derivatives. A mixture of LSNswas treated with porcine liver esterase (PLE-A) in acetone-phosphate buffer (pH = 6.7) at 37°C, after filtering off the enzyme, purification by Cosmosil column afforded LSN-H (Id) a...