The Origin of Pharmaceuticals

The importance of natural products in therapeutics has been generally recognized from immemorial time. The Amerindians' knowledge of hallucinogenic plants used for their religious rituals, as well as the aphrodisiac properties of several potions prepared from several plant species, have accompanied man for millennia. Throughout the ages, the search for the well-being and for the pleasure has always stimulated man to approach nature, teaching him to make good use of plants and their components. Although plants and microorganisms remain a major source of new drugs, natural products from marine sources have been actively investigated in recent decades. In fact, the possibility of finding new medicines from natural sources is one of the more old man’s activities and represents one of the most mentioned reasons for preserving biodiversity. The use of natural products as drug found several examples in therapeutics, as well as their use as an important template for molecular modification, being a crucial source of new original structural patterns that represents an authentic “molecular inspiration” for the design of new drugs. This chapter will cover the main natural products from plants, microorganisms and from marine sources that were developed to medicines and those that historically contributed as lead-compound for designing and discovery of more active and safer drug candidates.