Pharm Biol. 2000;38(4):302-7. doi: 10.1076/1388-0209(200009)3841-AFT302.
The water-soluble extract from a Paraguayan natural medicine, Nangapiry, the leaves of Eugenia uniflora L. (Myrtaceae), which has been used as an antidiabetic agent, was found to show inhibitory activities on the increase of plasma glucose level in the sucrose tolerance test (STT) conducted with mice. The portion adsorbed on a cation exchange resin was also found to inhibit a-glucosidases. From the active portion, two new active compounds named uniflorines A ( 1 ) and B ( 2 ) and known (+)-(3a, 4a, 5ß)-1-methylpiperidine-3, 4, 5-triol ( 3 ) were isolated. The structures of uniflorines A and B were determined as (-)-(1S, 2R, 6S, 7R, 8R, 8aR)-1,2,6,7,8-pentahydroxyindolizidine and (+)-(1S, 2R, 5R, 7R, 8S, 8aS)-1,2,5,7,8-pentahydroxyindolizidine by spectral means, respectively.
从被用作抗糖尿病剂的巴拉圭天然药物纳甘皮里（Nangapiry）的叶片，桃金娘科植物 Eugenia uniflora L. 中提取的水溶性提取物，在进行的蔗糖耐量试验（STT）中，显示出抑制血浆葡萄糖水平升高的活性。吸附在阳离子交换树脂上的部分也被发现抑制α-葡萄糖苷酶。从活性部分中分离出两种新的活性化合物，命名为 uniflorines A（1）和 B（2）以及已知的（+）-（3a，4a，5β）-1-甲基哌啶-3,4,5-三醇（3）。通过光谱手段分别确定了 uniflorines A 和 B 的结构为（-）-（1S，2R，6S，7R，8R，8aR）-1,2,6,7,8-五羟基吲哚里西啶和（+）-（1S，2R，5R，7R，8S，8aS）-1,2,5,7,8-五羟基吲哚里西啶。
