Cyanogenic Glycosides from Four Latin American Species of Acacia

The cyanogenic glucosides of four Latin American species of Acacia (Fabceae: Mimosoideae) have been isolated and characterized. Acacia atramentaria (Argentina) contains proacacipetalin, A.aroma (Argentina) linamarin and lotaustralin, A. tortuosa (Venezuela) proacacipetalin and a second presently uncharacterized glycoside, and A. globulifera (Guatemala) epiproacacipetalin which has not previously been reported as naturally occurring.     

苏铁蕨的化学成分

从蕨类植物苏铁蕨( Brainea insignis) 中分离得到1 个新的苯乙烯基吡喃酮苷, 利用波谱技术鉴定了其结构。此外, 还得到了1 个已知的苯乙烯基吡喃酮苷和4 个其它已知化合物。同时, 还测定了分离得到的两个苯乙烯基吡喃酮苷化合物的DPPH 自由基清除活性。     

Cyanogenic and non-cyanogenic pyridone glucosides from Acalypha indica (Euphorbiaceae)

Seven cyanopyridone derivatives and one corresponding seco compound have been isolated from a methanolic extract of the inflorescences and leaves of Acalypha indica L. (Euphorbiaceae). The absolute configuration of the main cyanogenic glucoside acalyphin, (−)-(5R,6S)-5-cyano-5-β-d-glucopyranosyloxy-6-hydroxy-4-methoxy-1-methyl-2(5,6-dihydro)-pyridone, was deduced from an X-ray crystallographic study. In addition, the 6R-epimer of acalyphin, epiacalyphin, and the corresponding pair of N-demethyl derivatives were isolated. The corresponding amide of acalyphin and a 1′,2′-glucosyl-fused epiacalyphin amide were isolated from air-dried material. Structural elucidation was performed by means of ¹H and ¹³C NMR-spectra, chiroptical methods such as CD-spectroscopy and optical rotation. Two further corresponding derivatives, an aromatized compound and an open-chain structure, were isolated from the aqueous phase.     

Two New Phenolic Glycosides from Viburnum cylindricum ( Caprifoliaceae)

从水红木( Viburnum cylindricum ) 植物中分离出2 个新化合物, 1- phloroglucinyl- ( 6-methybutyryl )-B-D- glucopyranoside命名为cylindrin A ( 1) , 1- [ 4- ( 3- hydroxy-l propyl ) ]- pyrocatechol- ( 6-methybutyryl )-B-D- glucopyranoside, 命名为cylindrin B ( 2) , 以及7 个已知化合物tachioside ( 3) , syingic acid-4-B-D- glucopyran oside ( 4) , 1-B-D-glucopyranosyloxy-3-methoxy-5- hydroxybenzene ( 5 ) , 4- hydroxy- 3-methoxypheno-l 1-O-B-D- glucoside ( 6 ) , 4-hydroxy- 2, 6- dimethoxypheno-
l 1-O-B-D- glucoside ( 7) , phlorogluc ino-l 1-O-B-D-glucoside ( 8 ) , 1-B-D- glucosyloxy-2- ( 3-methoxy- 4- hydroxyphenyl) propane- 1, 3- diol ( 9) . 它们的结构经波谱方法得到鉴定。3~ 9 为首次从该种植物中分离得到。     

A New Phenolic Constituent and a Cyanogenic Glycoside from Balanophora involucrata (Balanophoraceae)

Balanophora involucrata Hook .f. & Thomson (Balanophoraceae) is a parasite plant often growing on the roots of leguminous plants. The whole herb has been used medicinally for the treatment of irregular menstruation, cough, hemoptysis, traumatic injury and bleeding, dizziness and gastralgia in Yunnan Province, China. The 2,2‐diphenyl‐2‐picrylhydrazyl (DPPH) assay on the 60% aq. acetone extract of the fresh whole plant of B. involucrata showed considerable radical‐scavenging activity (SC₅₀ 15.3 μg/ml). Further purification on the extract led to the isolation of one new phenolic glycoside, sieboldin‐3′‐ketocarboxylic acid ( 1 ), and one new cyanogenic glycoside, proacacipetalin 6′‐O‐β‐D ‐glucopyranoside ( 2 ), together with 26 known compounds including three 4″‐O‐galloyl and 2″,3″‐O‐(S)‐hexahydroxydiphenoyl (HHDP) derivatives of dihydrochalcone glucosides, seven hydrolyzable tannins, and alkane glycosides. The cyanogenic compound isolated from the Balanophoraceae family for the first time might be a signal molecule between B. involucrata and its hosts. The free‐radical‐scavenging activity of the isolated compounds was also examined by DPPH assay.     

Cyanogenic glycosides from the rare Australian endemic rainforest tree Clerodendrum grayi (Lamiaceae)

The cyanogenic diglycoside lucumin ((R)-mandelonitrile-β-d-primeveroside) and monoglucoside prunasin ((R)-mandelonitrile-β-d-glucoside) were isolated from the foliage of the rare Australian rainforest tree species Clerodendrum grayi (Lamiaceae). This is the first reported isolation of the diglycoside lucumin from vegetative tissue (foliage), and the first reported co-occurrence of lucumin and prunasin. Furthermore, unusually, the diglycoside lucumin was the most abundant cyanogen accounting for approximately 60% of total cyanide in a leaf tissue.     

国产开唇兰属(兰科)一新种

南岭齿唇兰　新种　图 1ＡｎｏｅｃｔｏｃｈｉｌｕｓｎａｎｌｉｎｇｅｎｓｉｓＬ .Ｐ .ＳｉｕｅｔＫ .Ｙ .Ｌａｎｇ ,ｓｐ .ｎｏｖ .Ｆｉｇ.1Ａｃｏｎｇｅｎｅｒｉｂｕｓｄｉｆｆｅｒｔｐｌａｎｔｉｓｍｉｎｉｍｉｓｔａｎｔｕｍ 7.5～ 8.5ｃｍａｌｔｉｓ,ｓｅｐａｌｉｓａｌｂｉｓｄｏｒｓｏｓｔｒｉｉｓ 2ｌｏｎｇｉｔｕｄｉｎａｌｉｂｕｓｇｒｏｓｓｉｓｐｕｒｐｕｒｅｉｓｏｒｎａｔｉｓ,ｐｅｔａｌｉｓａｌｂｉｓｏｂｌｉｑｕｅａｎｇｕｓｔｅｑｕｅｌｉｎｅａｒｉ＿ｌａｎｃｅｏｌａｔｉｓｓｅｃｕｓｃｏｓｔａｍｓｔｒｉａ 1ｇｒｏｓ…     

Predispersal predation by rodents to beechnuts (Fagus crenata Blume)

The rodents predation intensity and discrimination ability toward the predispersal beechnuts (Fagus crenata) were investigated using a tree tower in a beech forest, central Japan in 1999 and 2000. In this stand, using seed traps, the densities of fallen viable nuts were 35.1m^–2 in 1999 and 8.4m^–2 in 2000. The vertebrate-damaged nuts had fallen 5.6 and 2.2m^–2 in 1999 and 2000, respectively. Yet, the crop of viable nuts in 1999 was not so rich as that in a mast year. In 1999, predispersal predation by rodents was recognized at 16–19m above ground through the bagging experiment. In 2000, there were no predispersal predation and yet we captured Apodemus argenteus three times and Glirulus japonicus frequently on the tree. Judging from the facts of their feeding behaviors and the tooth scars left on the cupules and nuts, Apodemus argenteus might have been more responsible for predation to the predispersal beechnuts rather than Glirulus japonicus. Apodemus argenteus population seemed to be abundant on the ground in both years. If the main agent of predispersal predator were Apodemus argenteus, their number shifted to the canopy would be much larger in 1999 than in 2000 according as the crop of viable nuts. In an additional experiment, rodents preferred intact cupules to insect-damaged cupules on the tree, suggesting that they discriminated the quality of the predispersal nuts, even in the cupule stage, through olfactory and/or visual senses. Thus, predispersal nut predation by rodents was prevalent during the limited period in autumn.     

中国马蓝属(爵床科)新组合和新分类群(英文)

采用广义的马蓝属(Strobilanthes Blume)概念,提出3个新组合:匍匐半插花(S.primulifolia(Nees)Y.F.DengJ.R.I.Wood),直立半插花(S.cumingiana(Forst.)Y.F.DengJ.R.I.Wood)和狭叶马蓝(S.atropurpurea var.stenophylla(C.B.Clarke)Y.F.DengJ.R.I.Wood);描述了8新种:南岭马蓝(Strobilanthes austrosinensis Y.F.DengJ.R.I.Wood)、冯氏马蓝(S.fengiana Y.F.DengJ.R.I.Wood)、陶氏马蓝(S.taoana Y.F.DengJ.R.I.Wood)、启无马蓝(S.wangiana Y.F.DengJ.R.I.Wood)、景东马蓝(S.atroviridis Y.F.DengJ.R.I.Wood)、西畴马蓝(S.rostrata Y.F.DengJ.R.I.Wood)、黄连山马蓝(S.spiciformis Y.F.DengJ.R.I.Wood)和匍匐马蓝(S.procumbens Y.F.DengJ.R.I.Wood)。对南岭马蓝、黄连山马蓝、景东马蓝和匍匐马蓝的花粉形态进行了观察。     

Flavonoids and other bioactive constituents from Ficus thonningii Blume (Moraceae)

Continued interest in the chemistry of Ficus spp. led to the investigation of the figs and the roots of Ficus thonningii Blume. Two new flavonoids, thonningiol (1) and thonningiisoflavone (2) along with nineteen known compounds were isolated. β-Isoluteone (13) was isolated here for the first time from a natural source. Their structures were elucidated on the basis of spectroscopic evidence. Interestingly, thonningiisoflavone (2) and hydroxyalpinumisoflavone (21) showed strong DPPH radical scavenging activity with IC₅₀ = 65.50 μM and 68.20 μM respectively compared to the standard BHA with IC₅₀ = 44.20 μM. The methanolic extract of figs, taxifolin (14), conrauiflavonol (17) and shuterin (19) exhibited moderate antimicrobial activity against six micro-organisms with MIC below 1.5 mg/mL.     

Properties of Purified L-Ornithine Decarboxylase (EC 4.1.1.17) from Tetrahymena thermophila

Ornithine decarboxylase (ornithine carboxy lyase; EC 4.1.1.17) (ODC) from Tetrahymena thermophila was purified 6,300 fold employing fractionated ammonium sulfate precipitation, gel permeation chromatography on Sephadex G-150, ion exchange chromatography on DEAE-Sepharose CL-6B, and preparative isoelectric focussing. The product obtained in 24% yield was a preparation of the specific activity of 10,200 nmol CO₂mdh^-1mdmg^-1. The purified enzyme was rather stable at 37°C (14% loss of activity within 1 h). The molecular and catalytic properties of this enzyme were investigated. The isoelectric point was 5.7 and the molecular weight (MW) was estimated to be 68,000 under nondenaturing conditions. The pH optimum was between 6.0 and 7.0, the K_m for the substrate L-ornithine was 0.11 mM, and the K_m for the cofactor pyridoxal 5-phosphate was 0.12 μM; the product of ODC catalysis, putrescine, was a poor inhibitor with an estimated K_i of about 10 mM. The enzyme was inhibited competitively by D-ornithine with a K_i of 1.6 mM and by α-difluoromethylornithine with a K_i of 0.15 mM. The latter one, an enzyme activated irreversible inhibitor of mammalian ODC, inactivated the enzyme from T. thermophila at high concentrations with a half life time of 14 min. Other basic amino acids, e.g. L-lysine, L-arginine, and L-histidine, were neither substrates nor inhibitors of the enzyme, as were the diamines 1,3-diaminopropanol and cadaverine, the polyamines spermidine and spermine and the cosubstrate analogues pyridoxal and pyridoxamine-5-phosphate. Polyanions were activators of the enzyme: The half maximal ODC stimulating concentrations were 2.2 μgmdml^-1 for RNA, 6.1 μgmdml^-1 for DNA, and 0.25 μgmdml^-1 for heparin. These results indicate that ODC from T. thermophila shares several properties with ODC preparations from other organisms but in some respects, especially in activator and inhibitor specificity, there are some special qualities unique to this particular protozoan enzyme.     

牛心朴子中三个新C21甾体配糖体

从宁夏产植物牛心朴子（Cymmehumkomarovii Al．IIjinski）须根的乙醇提取物中分离并鉴定了4个C21甾体配糖体：白前苷元C 3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α-L-吡喃磁麻糖基-（1→4）-β-D-吡喃毛地黄毒糖基-（1→4）-β—D-吡喃夹竹桃糖苷（1）,白前苷元A 3-O-β-D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α-D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃毛地黄毒糖基-（1→4）-β-D-吡喃夹竹桃糖苷（2）,白前苷元C3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α—D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃磁麻糖基-（1→4）-β-D-吡喃夹竹桃糖苷（3）,白前苷元A3-O-β—D-吡喃葡萄糖基-（1→4）-β-D-吡喃葡萄糖基-（1→4）-α—D-吡喃夹竹桃糖基-（1→4）-β-D-吡喃磁麻糖基-（1→4）-β-D-吡喃夹竹桃糖苷（4）,分别命名为komarosideI（1）,komarosideJ（2）,komarosideK（3）,komarosideL（4）,除化合物1外,其余化合物均为新化合物。