Drug lead generation

The major impetus for the development of solid phase synthesis centers around applications in combinatorial chemistry. The notion that new drug leads and catalysts can be discovered in a high tiuoughput fashion has been demonstrated many times over as is evidenced from the number of publications that have arisen (see references at the end of this chapter). A number of )proaches to combinatorial chemistry exist. These include the split-mix method, serial techniques and parallel methods to generate libraries of compounds. The advances in combinatorial chemistry are also accompani by sophisticated methods in deconvolution and identification of compounds from libraries. In a number of cases, innovative hardware and software has been developed tor these purposes. 

One early step in the workflow of the medicinal chemist is to computationally search for similar compounds to known actives that are either available in internal inventory or commercially available somewhere in the world, that is, to perform similarity and substructure searches on the worldwide databases of available compounds. It is in the interest of all drug discovery programs to develop a formal process to search for such compounds and place them into the bioassays for both lead generation and analog-based lead optimization. To this end, various similarity search algorithms (both 2D and 3D) should be implemented and delivered directly to the medicinal chemist. These algorithms often prove complementary to each other in terms of the chemical diversity of the resulted compounds [8]. 

Bleicher KH, Bohm HJ, Muller K, Alanine AI. Hit and lead generation beyond high-throughput screening. Nat Rev Drug Discov 2003 2 369-78. 

N. NMR experiments for lead generation in drug discovery. Prog. 

Bemis, G. W., Ajay, Murcko, M. A., Moore, J. M. The SHAPES strategy an NMR-based approach for lead generation in drug discovery. Chem. Biol. 1999, 6, 755-759. 

Structure-based lead generation, 44 (2006) 1 Synthesis of enantiomers of drugs, 34 (1997) 203... 

One advantage of whole-cell biotransformation that has not been addressed adequately in this chapter is the ability to modify compounds with complex structure, such as natural products. Natural products are ideal substrates for biotransformation reactions since they are synthesized in a series of enzymatic reactions by the whole cells. The modification of natural products by biotransformation has been reviewed recently by Azerad [ 13] and a majority of the modifications were carried out by whole-cell biotransformations. Additional examples of modification of natural products by whole-cell biotransformations can also be found in the review article by Patel [2]. Natural products are an important source of new drugs and new drug leads [53]. The use of biotransformation, especially whole-cell biotransformation, in modification of natural products for lead optimization and generating libraries of derivatives for S AR and screening studies is important for the pharmaceutical industry. 

The identification of compounds with a desired property is a central pursuit in science. In the field of drug discovery combinatorial chemistry has played an increasingly important role for identification and optimization of drug leads which target therapeutically important biomolecules. For the successful implementation of combinatorial methods, new and innovative synthesis methods have been developed. Additionally, novel conceptual approaches to the design of compounds have been pursued to more efficiently generate libraries of small molecules. 

Alanine, A., Nettekoven, M., Roberts, E., and Thoma, A.W. Lead generation - enhancing the success of drug... 

Goodnow R Jr Small molecule lead generation processes for drug discovery. Drugs Future 2002, 27, 1165-1180. 

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