Leon Henryk Sternbach was born on 7 May 1908 in picturesque Opatija, at that time a popular Adriatic resort, which lay within the Austro-Hungarian borders and is now in Croatia. He was the son of Michal Abraham Sternbach, an apothecary originally from Drohobych and a graduate of Lviv University. His father ran a pharmacy, which undoubtedly influenced Leon's future interests.

Leon began his schooling at grammar schools in Villach and Graz before moving to Bielsko-Biała in 1923, where he passed his matriculation exam in 1926. Soon afterwards, in search of further education, Sternbach moved to Kraków. There, following in his father's footsteps, he began studying at the Pharmaceutical Department of the Jagiellonian University. Krakow, being the Sternbach family haven, fostered his scientific passions. The Sternbachs were well known in the academic circles of the city, not only thanks to Michał's achievements, but also to other prominent members of the family, such as Leon Sternbach, the world-famous classical philologist, and Edward Dawid Sternbach, a gifted lawyer.

In 1929, Leon Sternbach earned a master's degree in pharmacy. He then continued his education, focusing on chemistry, resulting in a doctorate of philosophy in this field in 1931. His doctoral thesis, on alpha- and beta-acetonaphthalene derivative compounds, was an important step towards further research in organic chemistry. After defending his doctorate, Sternbach began working as an assistant in the Second Department of Organic Chemistry at the Jagiellonian University under Prof. Karol Dziewoński, where he was mainly involved in research on dyes.

These early years of training and scientific work were the foundation for Sternbach's later groundbreaking discoveries. His determination and relentless scientific curiosity, despite adversities such as the downsizing at the Jagiellonian University that forced him to leave the university, helped shape the character of the future scientist.

Scientific career before the Second World War
After completing his education at the Jagiellonian University, Leon Sternbach began his professional scientific career, continuing the work he had started as a doctoral student. His early research focused mainly on dyes and compounds, which was typical of organic chemistry of the time. In particular, he was interested in alpha- and beta-acetonaphthalene derivatives. These early works, although perhaps not as well-known as his later discoveries, were crucial in developing his research and experimental skills.

Working at the Second Department of Organic Chemistry at the Jagiellonian University under Professor Karol Dziewoński was not only an opportunity for Sternbach to further his scientific development, but also to study under one of the leading Polish chemists of the time. Unfortunately, the university's financial difficulties, which led to job cuts, forced Sternbach to leave academia. However, this unexpected change proved to be a turning point in his career, opening up new international opportunities.

Academic activities outside Poland
In 1937, Sternbach received a grant from the Felix Wiślicki Foundation, which allowed him to continue his research in Vienna and then in Zurich under the guidance of the future Nobel laureate, Professor L. Ruzicky. This period in his life was a time of intensive research and learning in an international scientific environment. There he continued the work he had begun while still in Krakow, expanding his research interests and establishing important scientific contacts.

The outbreak of the Second World War found Sternbach in Switzerland, which in a way protected him from the immediate effects of the conflict. On 1 June 1940, he began working for the pharmaceutical company Hoffman-La Roche in Basel, which proved decisive for his subsequent career. At Roche, Sternbach had the opportunity to work in one of the most innovative research environments in the pharmaceutical industry, which led to his later groundbreaking discoveries.

Revolution in pharmaceuticals: discovery of benzodiazepines
Sternbach's work at Hoffman-La Roche led to one of the most important breakthroughs in the history of medicine - the synthesis of benzodiazepines. His early work on the synthesis of vitamin H (biotin) was only a prelude to a discovery that was to revolutionise the treatment of nervous disorders. The benzodiazepines, led by chlordiazepoxide and diazepam (Valium), ushered in a new era in anti-anxiety, sedative and analgesic therapy.

Diazepam, launched in 1963 under the trade name Valium, quickly became one of the world's best-selling drugs. Its introduction was the result of Sternbach and his team's search for a substance that was safer and more effective than previously available sedatives. Valium, with its relaxant and anti-anxiety properties, became a symbol of pharmaceutical innovation, but also, as it later turned out, a challenge of its abuse and addiction.

Valium: success and controversy
Valium, discovered by Leon Sternbach, revolutionised the treatment of nervous disorders by offering an effective and rapid way to relax muscles and relieve anxiety. Its launch in 1963 under the name Valium marked the beginning of a new era in pharmacy. Thanks to its properties, Valium quickly gained recognition among doctors and patients alike, becoming one of the most widely prescribed drugs in the world.

The use of Valium also had negative effects. On the one hand, the drug brought relief to millions of people suffering from various types of nervous ailments. On the other hand, however, its wide availability and popularity led to abuse and addiction. Many people began to use Valium without proper medical monitoring, which in some cases led to serious health consequences. The problem of addiction to benzodiazepines, particularly Valium, has become so serious that it has forced the medical world to rethink the issue of responsible prescribing and use of psychotropic drugs.

Legacy and recognition
Despite the controversy surrounding Valium, Leon Sternbach's contribution to the development of modern pharmacy cannot be overstated. His work on benzodiazepines, including the discovery of diazepam, has contributed to significant advances in the treatment of nervous disorders and underpins many modern therapies. Sternbach is the author of more than 240 patents and his discoveries have contributed significantly to Roche's successes.

Sternbach was recognised not only in the scientific community, but also socially. He was inducted into the National Inventors Hall of Fame, where he was among such prominent figures as Alfred Nobel and Thomas Edison. His work was also honoured with a place in the New Jersey Inventor's Hall of Fame and the Medicinal Chemistry Hall of Fame.

The significance of Sternbach's legacy
Leon Sternbach left a legacy that continues to influence modern medicine and pharmacy. His work on benzodiazepines changed the way we view the treatment of nervous disorders, offering patients new and more effective therapies. At the same time, the story of Valium is a reminder of the need for a responsible approach to the use and prescription of psychotropic drugs.

The life and work of Leon Sternbach provide not only the story of a brilliant scientist who revolutionised pharmacy, but also a warning against the ill-considered application of scientific discoveries. His legacy remains important for both scientists and patients around the world.