萼翅藤枝叶挥发油及其抗菌活性的研究

萼翅藤枝叶挥发油由GC/MS检测.树叶挥发油的52种成分中,氧化石竹烯(13.79%)、棕榈酸(11.91%)和β-石竹烯(10.45%)是主要成分.同时,树枝挥发油中的10种成分占总量的99.99%,其中主要的化学成分为棕榈酸(59.18%),亚油酸(12.70%)和邻苯二甲酸丁辛酯(8.21%).用滤纸扩散法,分别测定了枝、叶挥发油对8种微生物的抑制效果.枝、叶挥发油均具有很强的抗菌效果,并且抗细菌活性优于抗真菌活性.叶挥发油比枝挥发油具有更广谱的抑菌效果,且对所试的大多数菌株都具有更高的活性.     

中国产光萼苔科四种植物的核型研究

报道了中国产光萼苔科四种植物配子体有丝分裂中期的染色体数目和核型,四种植物的染色体数目均为n=8。核型为：细光萼苔陕西变种(P．gracillima vat．urogea)k(n)=8=8m或k(n)=8=4v 4(v);毛缘光萼苔(P．vernicosa)k(n)=8=5m 3sm或k(n)=8=6v 2J;密叶光萼苔(P．densifolia)k(n)=8=8m或k(n)=8=5v 3(v);多瓣苔(Macvicaria ulophylla)k(n)=8=6m 2sm或k(n)=8=6v 1(v) 1J．     

无萼齿野豌豆的核型分析

无萼齿野豌豆(Vicia edentata Wang et Tang)是豆科野豌豆属的多年生草本植物,产我国浙江天目山、安徽黄山和山东青岛。 野豌豆属全世界约150种,其中有127种已有染色体数目的报道。这个属以染色体的多变性而著称,不仅染色体基数有5,6,7,9,11等变化,而且染色体的结构也是多变的。笔者对无萼齿野豌豆的染色体数目和核型首次作了报道,旨在为揭示野豌豆属的染色体进化的规律和机制提供部分资料。     

反萼银莲花的核型分析

本文报道反萼银莲花的染色体数目及核型。其核型公式为K(2n)=6m+4sm(1SAT)+4st(1SAT)+2t,按照Stebbins的核型对称性分类标准应属于“2A”型。同时对本属的进化等问题也作了初步讨论。     

省藤属四种植物的核型分析

报道了省藤属 (Calamus) 4种植物的核型 :小省藤 (C gracilis)的核型公式为 2n =2x =16m 10sm ,盈江省藤 (C nambariensisvar yingjiangensis)为 2n =2x =16m 10sm ,宽刺藤 (C platyacanthus)为 2n =2x =14m 12sm ,高地省藤 (C nambariensisvar alpinus)为 2n =2x =14m 12sm。其体细胞染色体数均为 2n =2 6 ,核型不对称性类型为 2B ,说明其种间染色体核型差异小。但小省藤臂比值大于 2的染色体占 12 % ,而宽刺藤、盈江省藤和高地省藤为 30 % ,说明在系统发育中 ,前者可能更为原始     

倒心盾翅藤的化学成分研究

从药用植物倒心盾翅藤（Aspidopterys obcordata Hemsl.）中首次分离得到５个化合物,通过波谱分析分别鉴定为木栓酮（１）、无羁萜－３β－醇（２）、二二烷酸甲酯（３）、１０－二九烷醇（４）、豆甾醇（５）和daphnetin-8-glucopyranoside(6)。     

翅萼龙胆中的两个寡聚裂环烯醚萜甙

从翅萼龙胆的全株中分离得到两个新的寡聚裂环烯醚萜甙：翅萼龙胆甙Ｉａ和Ｉｂ,其结构通过光谱分析推定。     

永瓣藤

永瓣藤成文法姚承霞１９２６年,年轻的中国植物学者秦仁昌,在安徽南部祁门县棕里村潘坑坞发现了一种新奇的藤本植物,当时拟名为“祁藤”。后经美国阿诺德树木园植物分类学家雷德尔（Ａ．Ｒｅｈｄｅｒ）定名为Ｍｏｎｉｍｏｐｅｔａｌｕｍｃｈｉｎｅｎｓｅ。因其花瓣宿存...     

思茅藤的化学成分研究

从思茅藤(Epigynum auritum (schneid.)Tsiang et P.T.Li)的茎皮中分离到一个新的化合物,命名为思茅藤甙(Epigcoside)Ⅰ和已知化合物Ⅱ。通过光谱分析和化学反应证明,其结构为Ⅰ(+)—儿茶素-3-O-α-D-葡萄吡喃糖(1→6)-β-D葡萄吡喃糖甙((+)-catchin—3-O-α-D-glucopyranosyl-(1→6)-β—D-glucopyranoside;Ⅱβ-谷甾醇β-D-葡萄糖甙(β-sitosterol-β-D-glucoside)。     

Five biflavonoids from Calycopteris floribunda (Combretaceae)

The structures of five biflavonoids, 6"-demethoxyneocalycopterone (1), calyflorenone C (2), 6"-epi-calyflorenone B (3), 6"-epi-calyflorenone C (4) and calyflorenone D (5) from the green parts of Calycopteris floribunda were established by NMR and MS. Their NMR and chiroptical properties (CD, [alpha]20D ) were compared with those of the known C. f. biflavonoids 6-11. Compound 1 represents a calycopterone derivative, 2-5 have a calyflorenone skeleton. With regard to one chiral center (C-6"), 4 and 3 are the respective epimers of 2 and 11.     

Synthesis of antiproliferative flavones from calycopterin, major flavonoid of Calycopteris floribunda Lamk

Eighteen new analogues of 5,3′-dihydroxy-3,6,7,8,4′-pentamethoxy-flavone, a potent natural cytotoxic and antimitotic flavone, were synthesized from calycopterin, the major flavonoid of Calycopteris floribunda Lamk., a traditional Asian medicinal plant. One of them, the 3′-amino substituted analogue, displayed almost the same activity as the reference compound. Pharmacomodulation at C-3′ on the B-ring, and at C-5,6,7 and 8 on the A-ring allowed to refine structure-activity relationships within the cytotoxic flavones series.     

九种报春花属植物的核形态学研究

对报春花属（Prinula)4个组9种植物进行了核形态学研究。这9个种的间期核构形均为复杂染色中心型,前期染色体属于中间型,体细胞有丝分裂中期染色体的数目及核型如下：中甸海水仙报表P.monticola(Hand.-Mazz.)Chen et C.M.Hu,K(2n)=16=12m 4sm;高穗花报春P.vialii Delavay ex Franch.,K(2n)=20=16m 2sm 2st;偏花报春P.secundiflora Franch.,K(2n)=22=18m 4sm;海仙花报春P.poissonii Fanch.,K(2n)=22=16m 6sm;霞红灯台报春P.beesiana Forr.,K(2n)=22=18m 4sm;桔红灯台报春P.bulleyana Forr., K(2n)=22=18m 4sm;橙红灯台报春P.aurantiaca W.W.Smith et Forr.,K(2n)=22=16m(sat) 6sm;粉被灯台报春P.pulverulenta Duthie,K(2n)=22=19m 2sm 1st;钟花报春P.sikkimensis Hook.,K(2n)=20=14m(1sat) 4sm 2T。其中,中甸海水仙报春和高穗花报春两种的染色体数目及核型为首次报道。同时,本文还将偏花报春与灯台组报春以及钟花组报春进行了细胞学的比较分析。     

A prenylated xanthone from Allanblackia floribunda

A new prenylated xanthone, named allanxanthone A, was isolated from the stem bark of Allanblackia floribunda in addition to known compounds, 1,5-dihydoxyxanthone, 1,5,6-trihydroxy-3,7-dimethoxyxanthone, stigmasterol and stigmasteryl-3-O-beta-D-glucopyranoside. The structure of the new compound was assigned as 1,3,5-trihydroxy-2-(3-methylbut-2-enyl)-4-(1,1-dimethylprop-2-enyl) xanthone, by means of spectroscopic analysis. The 13C NMR spectral data of 1,5-dihydroxyxanthone is reported here for the first time as well as the in vitro cytotoxic activity of xanthone metabolites against the KB cell line.     

Karyomorphological studies of theIxeris dentata complex on Mount Ishizuchi

The karyotypes of four taxa in theIxeris dentata complex collected from Mt. Ishizuchi were investigated.I. dentata subsp.dentata var.dentata f.dentata had 2n=21 in all the examined individuals and its karyotypes were classified into four different types. Var.dentata f.amplifolia showed 2n=21 in all individuals and had three different karyotypes.I. dentata subsp.dentata var.albiflora showed 2n=21 and two different karyotypes.I. dentata subsp.alpicola showed three different karyotypes with 2n=21 and four different ones with 2n=28. Judging from the results of the karyotype analyses, the morphological variation of chromosomes in theI. dentata complex is assumed to be in the process of increasing asymmetry in the shape of chromosomes. Following Levitzky's principle, it can be said that the a-, b-, and c-chromosomes exist in different advanced stages in the process of chromosome variation. The c-group chromosomes are at the most advanced stage in morphological variation, the b-group in the second and the a-group in the least advanced stage. The above-mentioned structural diversity of chromosomes may be related to apomictic reproduction of theI. dentata complex.     

Karyomorphological studies onWoodwardia sensu lato of Japan

Karyomorphological comparisons were made of five species of JapaneseWoodwardia. There were no marked differences at interphase and prophase among the five species.Woodwardia japonica, W. prolifera, andW. unigemmata were diploid with 2n=68 and the formulas of their metaphase karyotypes uniformly 4m(median centromeric chromosomes)+12sm(submedian)+52(st+t)(subterminal and terminal).Woodwardia orientalis was tetraploid with 2n=136 and 8m+24sm+104(st+t), and the ratio of each chromosomal type to total complement was identical to that of three diploid species. These four species had several characteristics in common:x=34, the longest chromosome of sm, and a mean chromosome length over 3.0 μm. AlthoughWoodwardia orientalis showed some similarity toW. prolifera, it seems to be an allotetraploid which originated by chromosome doubling of a hybrid ofW. prolifera and a diploid species as yet karyomorphologically unknown.Woodwardia kempii was tetraploid with 2n=124 and 8m+24sm+92(st+t), and differed from the others in havingx=31, the longest chromosomes of t, and a mean chromosome length under 3.0 μm. This species has been classified as an independent genus,Chieniopteris, and our karyomorphological study supports this treatment.     

Prenylated bisresorcinols from Grevillea floribunda

Seven new bisresorcinol derivatives, together with four known resorcinols, have been isolated from the ethyl acetate extract of the stems of Grevillea floribunda. Five of the new compounds (floribol A–E) were characterized as bisnorstriatol derivatives substituted at C-2 of both resorcinol units with variously modified prenyl (3-methylbut-2-enyl) units. The remaining two new compounds are similarly substituted derivatived of grebustol-B.