The medicinal use of natural products—compounds that are derived from natural sources such as plants, animals or micro-organisms—precedes recorded human history probably by thousands of years. Palaeoanthropological studies at the cave site of Shanidar, located in the Zagros Mountains of Kurdistan in Iraq, have suggested that more than 60,000 years ago, Neanderthals might have been aware of the medicinal properties of various plants, as evidenced by pollen deposits in one of the graves at the site (Solecki, 1975). Over the ensuing millennia, humankind discovered and made use of an enormous range of natural compounds; the latest version of the Dictionary of Natural Products (DNP; http://dnp.chemnetbase.com) has just over 214,000 entries.