DIVERSIFIED STUDIES ON DEVELOPMENT OF RARE MEDICINAL RESOURCE PLANTS IN RYUKYU ISLANDS

1.蛇床子细胞培养(1)培养愈伤组织代谢产物的研究：培养的愈伤组织产生了一组取代预期生物碱的蒽醌类化合物。鉴定了2个新分子1-羟基-2-羟甲基-3-甲氧基和2-丁氧甲基-1，3-二羟基-1，3-二羟基的结构。(2)小麦冬愈伤组织诱导分化植株：由愈伤组织诱导分化植株。对成分的研究表明，存在喜树碱、9-甲氧基喜树碱、短果糖苷和3(R)-脱氧木霉糖苷，证明其表达了与原始植物相同的生物碱形成酶活性。2.向生物合成模式合成喜树碱的一步：3-表木糖苷四乙酸酯转化为C-7脱氧衍生物。所得产物与天然脱氧香草苷的乙酸酯完全相同；这一观察结果要求我们将上述天然分子的C-3立体化学从α修改为β。3.新喜树碱衍生物的合成：合成了5个10-羟基喜树碱酯类化合物；饱和脂肪酸分别为10、12、16、18和20个碳的酯。哺乳动物的酯酶和拓扑异构酶I的生物活性测试正在进行中。4.斑潜蝇和斑叶斑潜蝇的成分研究：由于材料数量稀少，对灰斑狼疮的成分的研究未能成功。5.寻找新的药用资源植物：一些冲绳或热带亚洲植物物种的研究正在与东南亚国家的科学家密切联系中，这些植物包括茜草科(茜草科)、白花蛇舌草(茜草科)、GlyCosmis(茜草科)、Murraya(芸香科)或Acalypha(大戟科)等。

1.Cell cultivation of Ophiorrhiza pumila(1)Studies on metabolites of cultured callus : The cultured callus produced a group of anthraquinones instead of anticipated alkaloids. Structures of nine anthraquinones including two new molecules, 1-hydroxy-2-hydroxymethyl-3-methoxy anthraquinone and 2-butoxymethyl-1,3-dihydroxy anthraquinone, were elucidated.(2)Induction of differentiated plants from callus of Ophiorrhyza pumila : Regenerated plants were formed from the callus. Studies on the constituents revealed occurrences of camptothecin, 9-methoxycamptothecin, pumiloside, and 3(R)-deoxypumiloside, proving expression of the same alkaloid-forming enzyme activities as the original plant.2.A step toward biosynthesis-modeled synthesis of camptothecin : 3-epi-pumiloside tetraacetate was converted to the C-7 deoxy derivative. The resulting product proved to be identical with the acetate of natural deoxypumiloside ; an observation that required us to revise the proposed C-3 stereo chemistry of the above natural molecule form alpha to beta.3.Synthesis of new camptothecin derivatives : Synthesis of five esters of 10-hydroxycamptothecin was made ; esters with saturated fatty acids of 10,12,16,18 and 20 carbons, respectively. Biological activity tests for mammalian esterases and for topoisomerase I are under progress.4.Studies on the constituents of Vernonia cenerea and V.arborea : A study on the constituents of V.cinerea was unsuccessful because of scarece material amount. V.arborea native to South Thai gave a new lignan of unknown structure besides known 3-0-caffeoyl quinic acid.5.Search for new medicinal resource plants : Studies on some Okinawan or Tropical Asian plant species of such genera as Morrinda (Rubiaceae), Hedyotis (Rubiaceae), Glycosmis (Rutaceae), Murraya (Rutaceae), or Acalypha (Euphorbiaceae), are in progress under close contact with scientists in the countries of South East Asia.