I am currently studying the field of organic photochemistry. There are many organic compounds in our surroundings, and we are studying the synthesis of substances called lactones in them.
Lactone is a generic term for cyclic esters. Many lactones exist in nature. Three, four, five, six-membered ring lactones with ring numbers are called α, β, γ, δ-lactone, respectively. 7 to 11 membered ring lactone is collectively referred to as medium member lactone. And this time my theme of macrocyclic lactone is a generic name of lactone of more than 12 member rings. Many macrocyclic lactones show perfume, antitumor activity, and antibacterial activity. Antibiotics with a lactone structure have few side effects and are safe medicines. Therefore, it is important to develop a method for synthesizing macrocyclic lactones. The method of lactonization has a method called Yamaguchi lactonization, and recently, Shiina lactonization which improved Yamaguchi lactonization is often used. However, this method requires expensive acid anhydride.
In our laboratory, we found a photocyclization reaction as a synthesis method of lactonization. During the redox photosensitization reaction using phenanthrene and 1,4-dicyanobenzene, the decarboxylation reaction of the compound having a carboxy group proceeds and free radicals are formed. At this time, when an alkene is present, the alkyl radical reacts with the alkene. Lactones can be synthesized by performing this reaction in a molecule. This method is an environmentally friendly reaction without using expensive reagents. Therefore, I think that it is a useful reaction.
In our laboratory in the past, we have synthesized from 16-membered ring lactone to 18-membered ring lactone, 17-membered ring lactone to 19-membered ring lactone, 18-membered ring lactone to 20-membered ring lactone and 19-membered ring lactone to 21-membered ring lactone. These syntheses have many synthesis step and take time, which is a disadvantage. So I am studying to develop a synthesis method that reduces this synthesis step. In the synthesis step, we succeeded in reducing the number of steps. We also challenge the synthesis of macrocyclic lactones with further increased carbon number. I would like to synthesize a macrocyclic lactone with an even increased carbon number in the master's course two years.
In our laboratory, we found a photocyclization reaction as a synthesis method of lactonization. During the redox photosensitization reaction using phenanthrene and 1,4-dicyanobenzene, the decarboxylation reaction of the compound having a carboxy group proceeds and free radicals are formed. At this time, when an alkene is present, the alkyl radical reacts with the alkene. Lactones can be synthesized by performing this reaction in a molecule. This method is an environmentally friendly reaction without using expensive reagents. Therefore, I think that it is a useful reaction.
In our laboratory in the past, we have synthesized from 16-membered ring lactone to 18-membered ring lactone, 17-membered ring lactone to 19-membered ring lactone, 18-membered ring lactone to 20-membered ring lactone and 19-membered ring lactone to 21-membered ring lactone. These syntheses have many synthesis step and take time, which is a disadvantage. So I am studying to develop a synthesis method that reduces this synthesis step. In the synthesis step, we succeeded in reducing the number of steps. We also challenge the synthesis of macrocyclic lactones with further increased carbon number. I would like to synthesize a macrocyclic lactone with an even increased carbon number in the master's course two years.