A QSAR approach for virtual screening of lead-like molecules en route to antitumor and antibiotic drugs from marine and microbial natural products

Natural products (NPs), or synthetic products inspired by NPs, have been the single most productive source of leads for drug development. In fact, more than half of the approved drugs from 1981 to 2010 were based on NPs.1 At the turn of the 21st century, a new branch of NPs chemistry was fully established – Marine Natural Products (MNPs). The future seems very promising for this new NP subfield, since MNPs chemists have already elucidated the chemical structure of over 22,000 novel compounds.2 Moreover, from these, 7 are already approved drugs, (four anticancer, one antiviral, one pain control, and one hypertriglyceridemia).3 The success rate of drug discovery from the marine world is 1 drug per 3,140 natural products described. This rate is approximately 1.7- to 3.3-fold better than the industry average (1 in 5,000–10,000 tested compounds).4 Nowadays, there are facilities for high-throughput screening available both in academic labs or in pharmaceutical companies, but the cost of random screening for collections with a high number of compounds can nevertheless be prohibitive, making chemoinformatics approaches for virtual screening of the most probable active compounds valuable tools.