2-Hydroxy-8-azabicyclo[3.2.1]octan-6-yl acetate

DescriptionObtuseleaf Erycibe Stem (Ding Gong Teng) is one of the Chinese herbal medicines recorded by the Pharmacopoeia of the People’s Republic of China (2015). It is a dried rattan from the plants of Convolvulaceae Erycibe obtusifolia Benth. or Erycibe schmidtii Craib. and can be harvested all year. The indications of Ding Gong Teng included rheumatoid arthritis, hemiplegia, swelling, and pain. So Ding Gong Teng is used as a folk medicine to relieve the symptoms of rheumatism in Guangdong and Guangxi provinces. Erycibe alkaloid II belongs to scopolamine alkaloids, whose chemical structure is different from other known cholinomimetic drugs. It has remarkable effects in the treatment of glaucoma by contracting the pupils, reducing the intraocular pressure, and improving the aqueous humor coefficient. It has rare adverse reactions and mild side effects. So erycibe alkaloid II is an ideal drug for the treatment of glaucoma. The content of erycibe alkaloid II is only about one-hundred-thousandth of the original plant. Therefore, efficient synthesis of erycibe alkaloid II is very important for the further research.

Historying Gong Teng, as a folk herbal medicine for sweating and defervescence, is commonly known as “Zhu Mu Jiao” in Lufeng County of Guangdong province. Because of its serious side effects, Ding Gong Teng was once only applied to those patients with strong physical constitution. However, in the 1970s, pharmacological studies indicated that the water decoction of Ding Gong Teng showed a strong pupil contraction that was rare for other Chinese medicinal herbs. In that period of time, the source of pilocarpine and physostigmine used for pupil contraction was lacking in China, so a plenty of chemical and pharmacological research has been done in order to develop a new miotic for the treatment of glaucoma. There were few studies reported on the chemical composition of Obtuseleaf Erycibe Stem. In 1967, Sasorith, Souvan K. did some work about the chemical composition of Erycibe elliptilimba originated from Laos. That study reported that there were flavonoids in its leaves and tannin in its xylem, respectively, and its stems are not poisonous. Chinese scientists extracted two monomer compounds from the stem of Erycibe obtusifolia Benth. collected from Lufeng County, named as Baogongteng A (erycibe alkaloid II) and Baogongteng B. In the 1980s, the pharmacological studies of glaucoma treatment and the synthesis studies of erycibe alkaloid II were carried out promptly.