John Jacob Abel the position of chair of the department until he retired at the age of 75 in 1932. Ever since his early years in Europe, Abel showed great interest in isolating pure form of internal gland hormones. The first work that led to his international reputation as a pharmacologist and biochemist was the isolation of epinephrine from adrenal medulla. However, he was only able to isolate a monobenzoyl derivative of epinephrine. While he was improving his processes on decomposing the benzoyl derivative to obtain salts of epinephrine using saponification, a Japanese chemist J. Takamine, who had visited his lab, was able
Abel–Ruffini theorem was published by Pierre Wantzel in 1845. When he published it, he was already aware of the contributions by Galois and he mentions that, whereas Abel's proof is valid only for general polynomials, Galois' approach can be used to provide a concrete polynomial of degree whose roots cannot be expressed in radicals from its coefficients. In 1963, Vladimir Arnold discovered a topological proof of the Abel–Ruffini theorem, which served as a starting point for topological Galois theory. Abel–Ruffini theorem In algebra, the Abel–Ruffini theorem (also known as Abel's impossibility theorem) states that there is no algebraic solution—that is, solution in