Chin. J. Org. Chem. ›› 2014, Vol. 34 ›› Issue (9): 1786-1792.DOI: 10.6023/cjoc201403059 Previous Articles     Next Articles

一种合成拉坦前列素的新方法

修志明a, 王立成b, 黄梦媛a, 张鹏a, 郭佑铭a, 张闻起a, 王丽萍a   

  1. a 吉林大学生命科学学院, 长春 130012;
    b 吉林大学化学学院, 长春 130012
  • 收稿日期:2014-03-27 修回日期:2014-04-23 发布日期:2014-05-23
  • 通讯作者: 王丽萍 E-mail:wanglp@jlu.edu.cn
  • 基金资助:

    吉林省自然科学基金(No. 201015171)、吉林省科技发展计划(No. 201205017)、吉林省医药产业发展专项资金(No. YYZX201150-2)、长春市科技局社 会发展科技支撑计划(No. 12SF23)资助项目.

A Novel Method for the Synthesis of Latanoprost

Xiu Zhiminga, Wang Lichengb, Huang Mengyuana, Zhang Penga, Guo Youminga, Zhang Wenqia, Wang Lipinga   

  1. a School of Life Science, Jilin University, Changchun 130012;
    b School of Chemistry, Jilin University, Changchun 130012
  • Received:2014-03-27 Revised:2014-04-23 Published:2014-05-23
  • Supported by:

    Project supported by the Natural Science Foundation of Jilin Province (No. 201015171), the Scientific and Technological Planning Poject of Jilin Province (No. 201205017), the Pharmaceutical Industry Development Special Fundation Project of Jilin Province (No. YYZX201150-2), and the Social Development Science and Technology Supported Planning Project of Changchun Technology Bureau (No. 12SF23).

Latanoprost is a kind of PGF2α analogues, which is now one of the first-choice drugs in the clinic for open angle glaucoma and ocular hypertension. However, the previous synthetic methods have problems of long steps, low yield and difficult separation of isomeric impurities. Herein, we report a novel method for the synthesis of latanoprost in ten steps. Benzoyl Corey lactone as starting material was oxidized to form corresponding aldehyde by Dess-Martin oxidation. The ω side chain was bonded by improving Horner-Wadsworth-Emmons reaction with dimethyl(2-oxo-4-phenylbutyl)phosphonate and lithium chloride, and reduced with (-)-diisopinocampheyl chloroborane at -30 ℃ because of its greater selectivity towards the production of desired S-isomer (95%). The deprotection step wherein the protecting group of benzoyl on the hydroxyl group of the cyclopentane ring was removed, was preferably carried out by potassium carbonate in methanol. The hydrogenation of double bond in ω side chain was carried out by using 5% palladium-carbon as catalyst. The tetrahydropyranyl (THP) group was used for the protection of the diol with p-toluenesulfonic acid as catalyst. Latanoprost lactol was obtained by reducing the lactone with diisobutylaluminum hydride (DIBAL) at -78 ℃. α side chain of latanoprost was bonded by Wittig reaction with 4-carboxybutyl triphenylphosphoium bromide and NaHMDS forming phosphorus ylide. The carboxylic acid was alkylated with isopropyl iodide in the presence of 1,8-diazabicyclo(5.4.0)undec-7-ene (DBU), and then removed the THP protecting groups with pyridinium 4-toluenesulfonate (PPTS). Latanoprost was separated from two isomers of 15(S)-latanoprost and 5,6-trans-latanoprost after purification by normal-phase high performance liquid chromatography. Thus latanoprost was obtained with high purity of 99.91% and high overall yield of 19.2%, and the structure was characterized by 1H NMR, 13C NMR, IR and HRMS. Compared with the previous routes, the current synthesis is shorter, more practical, and more suitable for large-scale preparation.

Key words: benzoyl Corey lactone, latanoprost, synthesis, purification