Medicinal or pharmaceutical chemistry is a scientific regulation at the intersection of chemistry and pharmacy involved with designing, synthesizing and rising pharmaceutical drugs. Medicinal chemistry involves the identification, synthesis and development of fresh chemical entities suitable for therapeutic use. It also includes learn of existing drugs, their biological properties, and their quantitative structure-activity associations (QSAR). Pharmaceutical chemistry is focused on value aspects of medicines and aims to assure fitness for the reason of medicinal products.

Medicinal chemistry is a extremely interdisciplinary science combining organic chemistry with biochemistry, computational chemistry, pharmacology, molecular biology, statistics, and physical chemistry.

Discovery
The first step of drug discovery involves the recognition of new active compounds, often called "hits", which are classically found by screening many compounds for the desired biological properties. These hits can come from usual sources, such as plants, animals, or fungi. More often, the hits can come from artificial sources, such as historical complex collections and combinatorial chemistry.

Recent developments in robotics and miniaturization have really accelerated and automated the screening process. Naturally, a company will assay over 100,000 individual compounds before moving to the optimization step.

Optimization
The second step of drug discovery involves the synthetic change of the hits in order to get better the biological properties of the compound pharmacophore. The quantitative structure-activity relationship of the pharmacophore play an significant part in finding "lead compounds", which exhibit the most potency, the majority selectivity, best pharmacokinetics and least toxicity.

Development
The last step involves the rendering the "lead compounds" fit for use in clinical trials. This involves the optimization of the synthetic way for bulk production, and the preparation of an appropriate drug formulation.