For the isolation of biologically active compounds from organisms, several different steps need to be completed. The different steps required to obtain a biologically active compound are: Extraction, chromatographic purification, dereplication, structure elucidation and bioassay testing. The steps do not have to follow that particular order and many steps may be completed simultaneously. In the first step, the sample may be triturated and extracted with a suitable solvent or macerated. Some solvents used are methanol:chloroform, ethanol, acetonitrile, or others. The purpose is to remove organic compounds that have a medium polarity which are considered more "drug-like". Ideally,polar compounds like salts, peptides, sugars as well as very non-polar compounds like lipids are left behind to simplify chromatography since they are not generally considered "drug-like". Drying of the sample could be completed before extraction by lyophilisation to remove any excess water and therefore limit the amount of highly polar compounds extracted.