Solution-phase combinatorial chemistry

Integrated in Silico Methods for the Design and Optimization of Novel Drug Candidates

Although almost fully automated, the discovery of novel, effective, and safe drugs is still a long-term and highly expensive process. Consequently, the need for fleet, rational, and cost-efficient development of novel drugs is crucial, and nowadays the advanced in silico drug design methodologies seem to effectively meet these issues. The aim of this chapter is to provide a comprehensive overview of some of the current trends and advances in the in silico design of novel drug candidates with a special emphasis on 6-fluoroquinolone (6-FQ) antibacterials as potential novel Mycobacterium tuberculosis DNA gyrase inhibitors. In particular, the chapter covers some of the recent aspects of a wide range of in silico drug discovery approaches including multidimensional machine-learning methods, ligand-based and structure-based methodologies, as well as their proficient combination and integration into an intelligent virtual screening protocol for design and optimization of novel 6-FQ analogs.

High-throughput purification of compound libraries

Synthesis of combinatorial libraries by parallel synthesis, followed by high- throughput biological screening, is the new paradigm for drug discovery. Purity of these libraries is an important consideration to obtain high-quality assay data. Liquid-liquid extraction and solid-phase capture reagents are useful in special cases for small numbers of compounds. However, for libraries of a few thousand compounds, HPLC is a viable alternative. Beyond these numbers, factors such as solvent requirements, the number of fractions and tracking become prohibitive. Supercritical fluid chromatography has been successfully employed in automated purification instrumentation and is expected to be capable of purifying libraries of tens-of-thousands of compounds.

Parallel solution synthesis of pyridinethiones, pyridinones and thienopyridines

The parallel solution synthesis of three classes of heterocycles is described. Arrays of pyridinethiones, pyridinones and thienopyridines were prepared using one-step chemistry starting from readily accessible building blocks. The latter class of compounds was accessed by utilising a library-from-library approach.