Organic Chemistry Department, Global Research and Development, The Coca-Cola Company, Atlanta, GA 30313, USA.
Int J Mol Sci. 2013 Jul 26;14(8):15669-80. doi: 10.3390/ijms140815669.
Catalytic hydrogenation of the exocyclic double bond present between C16 and C17 carbons of the four ent-kaurane diterpene glycosides namely rebaudioside A, rebaudioside B, rebaudioside C, and rebaudioside D isolated from Stevia rebaudiana has been carried out using Pt/C, Pd(OH)2, Rh/C, Raney Ni, PtO2, and 5% Pd/BaCO3 to their corresponding dihydro derivatives with 17α and 17β methyl group isomers. Reactions were performed using the above-mentioned catalysts with the solvents methanol, water, and ethanol/water (8:2) under various conditions. Synthesis of reduced steviol glycosides was performed using straightforward chemistry and their structures were characterized on the basis of 1D and 2D NMR spectral data, including a comparison with reported spectral data.
已使用 Pt/C、Pd(OH)2、Rh/C、Raney Ni、PtO2 和 5%Pd/BaCO3 将甜菊叶中分离得到的四个 ent-贝壳杉二萜糖昔，即莱鲍迪甙 A、莱鲍迪甙 B、莱鲍迪甙 C 和莱鲍迪甙 D 中 C16 和 C17 碳原子之间的环外双键催化氢化，得到相应的二氢衍生物，其中 17α 和 17β 甲基异构体。反应在甲醇、水和乙醇/水（8:2）等溶剂中，使用上述催化剂在不同条件下进行。还原甜菊昔昔的合成采用了简单的化学方法，并根据 1D 和 2D NMR 谱数据（包括与报道谱数据的比较）对其结构进行了表征。
