Natural Product Synthesis: Changes over Time

摘要

The chemical synthesis of natural products, that is, of substances produced by living organisms, marked the beginning of organic chemistry. The synthesis of urea from inorganic ammonium cyanate by Woehler in 1828 demonstrated that natural products, despite being derived from living organisms, are amenable to in vitro synthesis in the laboratory. With this mental barrier being removed, the path was clear for the first targeted synthesis of a natural product, that of acetic acid. Targeted synthesis of a compound requires unambiguous knowledge of its constitution: at the time, this knowledge had to be based on the structural theories of Kekule (1858) and Butlerov (1861). However, such a structural formula, postulated by degradation of a natural product, was little more than a simple working hypothesis. Only by synthesizing this compound from small, structurally defined building blocks, using reactions with a clearly defined scope, did a proposed structure reach the state of being securely determined. Hence, in the early times of natural product synthesis, the underlying incentive was to confirm the structures of natural products.