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has been cited by the following article:

• TITLE: Synthesis of Vildagliptin-β-O-Glucuronide

  AUTHORS: Yansong Jack Lu, Yugang Liu, Mahavir Prashad, Wen-Chung Shieh

  KEYWORDS: Vildagliptin; O-Glycosylation; DPP-4 Inhibitors; Type-2 Diabetes

  JOURNAL NAME: Advances in Chemical Engineering and Science, Vol.2 No.3, July 11, 2012

  ABSTRACT: A linear 7-step synthesis of vildagliptin-β-O-glucuronide (2) starting from commercially available D-glucurono-6, 3-lactone (3) was herein achieved with 11.3% overall yield. Efficient preparation of compound 6 in pure α form was obtained, which was proved critical to achieve high anomeric selectivity in β-O-glycosylation later. The direct β-O-glycosylation of vildagliptin (1) containing both a tertiary alcohol and a secondary amine was studied and achieved in good yield. The deprotection step to afford product was delicately executed to avoid hydrolysis of nitrile group. The target compound 2 was obtained after purification by reversed-phase C18 chromatography.