Characterization of New Ent-kaurane Diterpenoids of Yunnan Arabica Coffee Beans

Coffea arabica L., commonly known as coffee and widely distributed throughout the world, involving Africa, Latin America and Asia, is a very popular hot drink around the world because of its attractive aroma and unique taste [ 1 , 2 ]. Previous studies have shown that coffee beans are consisted of caffeine, chlorogenic acids, saccharides [ 3 – 5 ], as well as diterpenoids, although, taking a minor proportion in the chemical constituents of coffee. However, due to their broad spectrum of biological activities, such as cytotoxicity, antioxidant, anti-inflammatory, researchers have carried out work on diterpenoids components from coffee beans, and found nearly 90 diterpenoids [ 6 – 9 ]. Yunnan Arabica Coffee was the Coffea arabica which were planted in Yunnan province. Along with the planting scale expanded to 120 thousand hectares, Yunnan province became a well-known cultivation base of C. arabica in the world. In order to investigate the chemical constituents of Yunnan Arabica Coffee and find bioactivity diterpenoids, we took Yunnan Arabica Coffee green beans collected in Dehong as the subject, and discovered five new ent -kaurane diterpenoids, along with seven known diterpenoids (Fig. 1 ). Herein, the isolation, structural elucidation, and their relevant bioactivities were also described.