Laboratory of Food Biochemistry, Division of Applied Bioscience, Graduate School of Agriculture, Hokkaido University, Kita-ku, Sapporo, Hokkaido 060-8589, Japan.
Molecules. 2017 Aug 31;22(9):1450. doi: 10.3390/molecules22091450.
Higenamine is a tetrahydroisoquinoline present in several plants that has β-adrenergic receptor agonist activity. Study of the biosynthesis of higenamine has shown the participation of norcoclaurine synthase, which controls the stereochemistry to construct the ()-isomer. However, when isolated from nature, higenamine is found as the racemate, or even the ()-isomer. We recently reported the isolation of higenamine 4'--β-d-glucoside. Herein, its ()- and ()-isomers were synthesized and compared to precisely determine the stereochemistry of the isolate. Owing to their similar spectral properties, determination of the stereochemistry based on NMR data was considered inappropriate. Therefore, a high-performance liquid chromatography method was established to separate the isomers, and natural higenamine 4'--β-d-glucoside was determined to be a mixture of isomers.
盐酸育亨宾是一种存在于多种植物中的四氢异喹啉，具有β-肾上腺素能受体激动剂活性。对盐酸育亨宾生物合成的研究表明，它涉及到诺卡枯林合酶，该酶控制立体化学以构建（）-异构体。然而，当从自然界中分离出来时，盐酸育亨宾通常以外消旋体或甚至（）-异构体的形式存在。我们最近报道了盐酸育亨宾 4'-O-β-D-葡萄糖苷的分离。在此，我们合成了其（）-和（）-异构体，并对其进行了比较，以精确确定分离物的立体化学。由于它们具有相似的光谱性质，因此认为基于 NMR 数据确定立体化学是不合适的。因此，建立了高效液相色谱法来分离异构体，并确定天然盐酸育亨宾 4'-O-β-D-葡萄糖苷是异构体的混合物。
