Complex sentence: The formula of suramin was kept secret by Bayer for commercial reasons, however, it was elucidated and published in 1924 by Ernest Fourneau and his team of the Pasteur Institute.
Split into simpler sentences: The formula of suramin was kept secret by Bayer for commercial reasons. But it was elucidated and published in 1924 by Ernest Fourneau and his team of the Pasteur Institute.