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Woodward is a rare organic chemist who has made epoch-making achievements in the experiment and theory of organic synthetic chemistry. He synthesized many complex organic compounds, such as cholesterol, corticosterone, brucine, reserpine, chlorophyll and so on. According to incomplete statistics, he has synthesized more than 24 kinds of complex organic compounds that are extremely difficult to synthesize, so he is called "the father of modern organic synthesis".

Woodward also discovered the structure and function of complex organic compounds such as chlortetracycline, oxytetracycline and tetrodotoxin, explored the synthesis of nucleic acid and protein, and discovered Woodward's organic reaction and Woodward's organic reagent named after him. He has unique insights and outstanding contributions in many fields such as organic chemical synthesis, structural analysis and theoretical explanation. He also independently proposed the sandwich structure of ferrocene, which was completely consistent with the research results of British chemists G. Wilkinson CN and E.O.Fischer.

From 65438 to 0965, Woodward won the Nobel Prize in Chemistry for his outstanding contribution to organic synthesis. After winning the prize, he didn't stop working because of his success. It is developing towards more arduous and complex chemical synthesis. "He organized 1 10 chemists from 14 countries to tackle key problems and explore the synthesis of vitamin B 12. Before him, this extremely important drug could only be extracted manually from animal viscera, so it was extremely expensive and in short supply.

The structure of vitamin B 12 is extremely complicated. Woodward found that it has 18 1 atoms, which is distributed in space like a magic carpet and is extremely fragile. It will decompose under the action of strong acid, strong alkali and high temperature, which makes it very difficult to synthesize artificially. Woodward designed a splicing synthesis scheme, that is, the various parts of vitamin B 12 were synthesized first, and then they were docked. This method later became a common method to synthesize all organic macromolecules.

In the process of synthesizing vitamin B 12, there are not only problems of creating new synthetic technology, but also organic theoretical problems that cannot be explained by traditional chemical theory. For this reason, Woodward referred to the "frontier orbital theory" put forward by Japanese chemist Kenichi Fukui, and put forward the conservation of molecular orbital symmetry with his student and assistant Hoffman, and explained many organic chemical processes simply and intuitively with symmetry, such as electric ring reaction, cycloaddition reaction, σ bond migration and so on. This principle points out that when the external orbital symmetry of reactant molecules is consistent, the reaction is easy to proceed, which is called "symmetry permission". When the external orbital symmetry of reactant molecules is inconsistent, the reaction is not easy to proceed, which is called "symmetry prohibition". With the establishment of molecular orbital theory, Hoffman and Kenichi Fukui jointly won the 198 1 Nobel Prize in chemistry. Because Woodward had been dead for two years at that time, and the Nobel Prize was not awarded to the dead scientist, the academic circles thought that if Woodward were still alive, he would be one of the winners, and then he would become one of the few scientists who won the Nobel Prize twice.

When Woodward synthesized vitamin B 12, he did nearly a thousand complex organic synthesis experiments, which lasted for 1 1 year, and finally realized it a few years before his death, and completed the complex synthesis of vitamin B 12. The chemists involved in the synthesis of vitamin B 12 are not only Hoffman, but also the famous Swiss chemist A.Escheni 1 1oser.

2. Cory)(m also Cory) (M.)

In 1960s, Corey created a unique method of organic synthesis-inverse synthesis analysis, which added new content to the realization of organic synthesis theory. Different from the early practice of chemists, the inverse synthesis analysis method starts with small molecules, repeatedly tries what kind of molecules they can form-the structure of target molecules, and analyzes which chemical bonds can be broken, thus breaking complex macromolecules into smaller parts, which are usually available or easy to obtain. It is very easy to synthesize complex organic compounds from these simple materials. His research has successfully made the synthesis of plastics, man-made fibers, pigments, dyes, pesticides and drugs easy, and the chemical synthesis steps can be designed and controlled by computers. ? He also used inverse synthesis analysis to synthesize 100 kinds of important natural substances in test tubes. Before that, people thought that natural substances could not be synthesized artificially. Professor Corey also synthesized physiologically active substances that affect blood coagulation and immune system function in human body. The research results have prolonged people's life and enjoyed a higher level of life.

His synthetic work mainly involves (1) macrocyclic structure (2) heterocyclic structure (3) sesquiterpenes (4) polycyclic isoprene compounds (5) prostate compounds (6) leukotrienes.