Ent-2α-hydroxy-13-epi-manoyl oxide from Sideritis perfoliata

A new ent-13-epi-manoyl oxide derivative was isolated from the aerial part of Sideritis perfoliata. Its structure, ent-2α-hydroxy-8,13β-epoxy-labd-14-ene, was established by chemical and spectroscopic means.     

A diterpenoid of the atis-16-ene class from Elaeoselinum foetidum

A new diterpenoid has been isolated from the root of Elaeoselinum foetidum. Its structure was established as ent-15α-senecioxy-atis-16-en-19-oic acid mainly by ¹H NMR ¹³C NMR spectroscopic studies of its methyl ester derivative.     

3-O-feruloyl-4-O-caffeoylquinic acid from coffee beans

A new phenolic ester was isolated from unroasted robusta coffee beans (Coffea canephora) by HPLC. The isolated compound was identified as an ester of caffeic acid and ferulic acid with quinic acid (3-O-feruloyl-4-O-caffeoylquinic acid) using ¹H NMR and mass spectroscopy.     

Ribonucleic acid from coffee beans

A method of extraction of RNA from coffee based on phenol treatment is described. Effectsf of various agents and pH of the extracting buffer on the efficiency of extraction were studied. The best extracting solution is 0·2 M Tris-HCl buffer at pH 7·4 with 1% sodium dodecyl sulphate and 0·05% EDTA. RNA (5–6%) is lost in the tissue residue and 4·6% in the interphase layer. No significant deviation of the spectral characteristics of the RNA solutions obtained from three samples of coffee from that for purified yeast RNA is observed. The purine-pyrimidine ratio for the RNA has been found to be in the range of 1·25–1·38.     

The biosynthesis of caffeine in the coffee plant

Leaf disks of Coffea arabica were infiltrated simultaneously with L-methionine-(methyl-¹⁴C) and with various possible precursors of caffeine biosynthesis. The results permit the identification of theobromine, 7-methylxanthine and 7-methylxanthosine as precursors of caffeine. 7-methylguanosine seems not to be an intermediate in caffeine formation.     

Changes in the composition of coffee leaf wax with development

Coffee leaf wax contains alkanes, free primary alcohols and free acids, together with unidentified substances. The relative amounts of each fraction varied with age: alkanes from 22–35% alcohols from 28-25%, and free acids from 22-14%. The major homologues of the alkane fraction were C₂₉ and C₃₁, of the alcohol fraction C₃₀ and C₃₂ and of the acid fraction C₂₈, C₃₀ and C₃₂. The ratio of both C₂₉:C₃₁ alkanes and C_3O:C₃₂ alcohols changed from 1:1 to 1:2 during development, although their combined sum in each case remained constant at 90% (for alkanes) and 73% (for alcohols) of the weight of the respective fractions.     

Acide nor-19 anticopalique d'Agathis lanceolata

A new diterpenoid, 19-noranticopalic acid, has been isolated from Agathis lanceolata resin. Its structure has been established by spectroscopic methods and chemical correlations with anticopalic acid.     

瓜叶乌头中生物碱成分的研究

从瓜叶乌头 (AconitumhemsleyanumPritz)根中分得 12个已知C19 二萜生物碱 ;氨茴酰牛扁碱(anthranoyllycoctonine) 1、牛扁碱 (lycoctonine) 2、8 去乙酰滇乌碱 (8 deacetylyunaconitine) 3、伪乌头宁(pseudaconine) 4、sachaconitine 5、尼奥宁 (neoline) 6、senbusineA 7、6 表弗斯生 (6 epiforesticine) 8、滇乌碱(yunaconitine) 9、印乌碱 (indaconitine) 10、查斯曼宁 (chasmanine) 11、和塔拉萨敏 (talatisamine) 12。其中化合物 1～ 8是首次从该植物中分离得到。应用光谱法和对照TLC鉴定了所有化合物的结构。     

Conflicting phylogenetic signals in genomic data of the coffee family (Rubiaceae)

Reconstructions of phylogenetic relationships in the flowering plant family Rubiaceae have up until now relied heavily on single‐ or multi‐gene data, primarily from the plastid compartment. With the availability of cost‐ and time‐efficient techniques for generating complete genome sequences, the opportunity arises to resolve some of the relationships that, up until now, have proven problematic. Here, we contribute new data from complete 58 plastid genome sequences, representing 55 of the currently 65 recognized tribes of the Rubiaceae. Also contributed are new data from the nuclear rDNA cistrons for corresponding taxa. Phylogenetic analyses are conducted on two plastid data sets, one including data from the protein coding genes only, and a second where protein coding data are combined with non‐coding regions, and on a nuclear rDNA data set. Our results clearly show that simply adopting a “more characters” approach does not resolve the relationships in the Rubiaceae. More importantly, we identify conflicting phylogenetic signals in the data. Analyses of the same plastid data, treated as nucleotides or as codon‐degenerated data, resolve and support conflicting topologies in the subfamily Cinchonoideae. As these analyses use the same data, we interpret the conflict to result from erroneous assumptions in the models used to reconstruct our phylogenies. Conflicting signals are also identified in the analyses of the plastid versus the nuclear rDNA data sets. These analyses use data from different genomic compartments, with different inheritance patterns, and we interpret the conflicts as representing “real” conflicts, reflecting biological processes of the past.     

A flavone glycoside from the stem of Ixora arborea

A new flavone glycoside isolated from the stem of Ixora arborea has been characterized as chrysin 5-O-β-D-xylopyranoside on the basis of spectral data, colour reactions and degradation studies.     

Cytotoxic diterpenoids from the aerial parts of Scoparia dulcis

Two formerly undescribed labdane-type diterpenoids, scoparicols C (1) and D (2), one previously unreported scopadulane-type diterpenoid 1β-hydroxydulcinodal-13-one (3), along with six known biogenetically related analogs (4−9) were separated from the aerial parts of a traditional ethnological herb, Scoparia dulcis. Spectroscopic techniques including MS NMR and ECD were employed to characterize the structures of these molecules. While the oxidation at C-1 in 3 was reported for scopadulane-type diterpenoids for the first time, compound 7 was first obtained as a natural product in the present work. The cytotoxicity of all the isolates against four tumor cell lines (MCF-7, MDA-MB231, Hela and A549) were tested, with selective compounds showing activity in the IC₅₀ range of 4.31–28.6 μM.     

Polyphenoloxidase activity in coffee leaves and its role in resistance against the coffee leaf miner and coffee leaf rust

In plants, PPO has been related to defense mechanism against pathogens and insects and this role was investigated in coffee trees regarding resistance against a leaf miner and coffee leaf rust disease. PPO activity was evaluated in different genotypes and in relation to methyl-jasmonate (Meja) treatment and mechanical damage. Evaluations were also performed using compatible and incompatible interactions of coffee with the fungus Hemileia vastatrix (causal agent of the leaf orange rust disease) and the insect Leucoptera coffeella (coffee leaf miner). The constitutive level of PPO activity observed for the 15 genotypes ranged from 3.8 to 88 units of activity/mg protein. However, no direct relationship was found with resistance of coffee to the fungus or insect. Chlorogenic acid (5-caffeoylquinic acid), the best substrate for coffee leaf PPO, was not related to resistance, suggesting that oxidation of other phenolics by PPO might play a role, as indicated by HPLC profiles. Mechanical damage, Meja treatment, H. vastatrix fungus inoculation and L. coffeella infestation caused different responses in PPO activity. These results suggest that coffee resistance may be related to the oxidative potential of the tissue regarding the phenolic composition rather than simply to a higher PPO activity.     

A diterpenoid from Elaeoselinum foetidum

A new diterpene acid has been isolated from the roots of Elaeoselinum foetidum. Its structure was established as ent-7α-senecioxy-15α-hydroxy-atis-16-en-19-oic acid by ¹H NMR and ¹³C NMR spectroscopic studies of its methyl ester derivative and confirmed by correlation with a margotianin derivative.     

Two new 11-noriridoids from the aerial parts of Morinda umbellata

This work was done as a part of our ongoing projects to catalog the chemical constituents and biological activities of the Morinda species growing in Vietnam. Phytochemical investigations of the methanol extract of Morinda umbellata aerial parts resulted in the isolation of two new 11-noriridoids, umbellatolides A (1) and B (2). Their structures were elucidated by NMR (¹H NMR, ¹³C NMR, HSQC, HMBC, ¹H–¹H COSY, and NOESY) and FTICRMS data. This is the first report of 11-noriridoids from M. umbellata. The cytotoxic activity and protective effect on oxidative stress injury stimulated by H₂O₂ in murine hepatocyte of 1 and 2 were also evaluated.     

Iridoid glucosides from the stems of three bioactive Brazilian Faramea species (Rubiaceae)

In this paper our previous chemical study of the anti-dengue active species Faramea bahiensis, Faramea hyacinthina and Faramea truncata (synonym of Faramea caudata) (Rubiaceae) is complemented by isolating from their stems, through a combination of silica gel and Sephadex LH-20 column chromatography and reversed-phase solid-phase extraction, the known iridoid glucosides monotropein (1), monotropein methyl ester (2) and 10-deacetylasperulosidic acid (3). The structures were established by HPLC-DAD-MS/MS analysis, NMR spectroscopy and comparison with literature data. This is the first report on the occurrence of these compounds in the genus Faramea Aubl. This work contributes to expand the knowledge of the chemical diversity of this botanical genus, of which a limited number of identified compounds have been reported.     

8β-hydroxypimar-15-en-19-oic acid from Taxodium mucronatum

A new diterpenoid has been isolated from the leaves and fruits of Taxodium mucronatum. Its structure, 8β-hydroxypimar-15-en- 19-oic acid, was established by chemical and spectroscopic means.     

Margotianin,a new diterpenoid from Margotia gummifera

From the roots and aerial parts of Margotia gummifera a new natural diterpenic methyl ester, margotianin, has been isolated. Its structure was established as methyl ent-7α-angeloxy-15α-acetoxy-atis-16-en-19-oate almost exclusively by ¹³C NMR spectroscopy.     

Ent-3,4-seco-labdane and ent-labdane diterpenoids from Croton stipuliformis (Euphorbiaceae)

From a methanolic extract of the leaves of Croton stipuliformis, three ent-3,4-seco-labdanes (1-3) and an ent-labdane (4) together with the known compounds 6-hydroxynidorellol (5), maravuic acid, and sitosterol were isolated and identified from their spectroscopic data. The absolute stereochemistry of compound 4 was determined by application of Mosher's method in the NMR tube.     

峨眉翠雀花中生物碱成分的研究

从峨眉翠雀花(Delphinium omeiense)块根中分得12个已知生物碱氨茴酰基牛扁碱(anthranoyllycoctonine)1、牛扁碱(lycoctonine)2、甲基牛扁碱(methyllycaconitine)3、德尔塔生(deltatsine)4、德尔色明甲(delsemine A)5、德尔色明乙(delsemine B)6、delsoline 7、potanine 8、delectine 9、delectinine 10、isodelectine11、kusnesoline 12,除1、2和3外,其余化合物均系首次自该植物中分得.应用光谱学和化学方法鉴定了报告的所有化合物的结构.