Drug Discovery with Novel Chemical Libraries

Several drug discovery and design endevours are focused on an exhaustive exploration of the drug-like chemical space with the final goal of identifying compounds that can be developed clinically. The traditional drug-like chemical space has been defined using old drugs with empirical rules such as the Lipinski’s Rule-of-Five (RO5). Therefore, promising drug candidates may be overlooked because they are outside the boundaries of currently aproved drugs. For instance, studies comparing drugs launched prior to 1983 and drugs launched between 1983 and 2002 reveal that the mean and median molecular weight and number of rotatable bonds are larger in new drugs [1,2]. Remarkable and well-known exeptions to the RO5 are several natural products that are bioavailable [3]. Fortunatelly, there is an increased awarness in the scientific community to explore novel regions of the medicinally relevant chemical space beyond the Lipinski’s RO5 and other similar empirical rules [1,2,4].