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1.
From the fresh leaves of Sophora tomentosa, three new lupin alkaloids, (?)-epilamprolobine, (+)-epilamprolobine N-oxide and 5-(3′-methoxycarbonylbutyroyl)aminomethyl-trans-quinolizidine N-oxide, have further been isolated along with (+)-matrine, (+)-matrine N-oxide, (+)-sophocarpine N-oxide, (?)-anagyrine, (?)- baptifoline, (?)-cytisine, (?)-N-methylcytisine, (?)-N-formylcytisine, (?)-N-acetylcytisine and (±)-ammodendrine. The absolute configurations of (+)-epilamprolobine N-oxide (1R:5R:6S) and (?)-epilamprolobine (5R:6S) have also been established by spectroscopic data and by comparison with synthetic (+)-epilamprolobine (5S:6R)derived from (?)-lupinine (5R:6R). (?)-Epilamprolobine is a diastereomer of (+)-lamprolobine (5R:6R) in Lamprolobium fruticosum and 5-(3′-methoxycarbonylbutyroyl) aminomethyl-trans-quinolizidine N-oxide is presumed to be an artefact. A biosynthetic pathway for the formation of (?)-epilamprolobine is also proposed.  相似文献   

2.
From the flowers of Sophora flavescens, a new dipiperidine-type alkaloid, (+)-kuraramine, has been isolated together with (+ )-mamanine and the oth  相似文献   

3.
The first synthesis of (?)-isishippuric acid A was accomplished in two steps from a bicyclic synthetic intermediate for isishippuric acid B, which confirmed the structure of isishippuric acid A, including its absolute stereochemistry.  相似文献   

4.
《Phytochemistry》1987,26(12):3375-3377
A new β-carboline dimeric alkaloid, (±)-picrasidine-T was isolated from the bark of Picrasma quassioides. The structure was determined by spectral analysis and chemical evidence.  相似文献   

5.
Chemical investigations of the MeOH extract of air dried flowers of the Australian tree Angophora woodsiana (Myrtaceae) yielded two new β-triketones, woodsianones A and B (1, 2) and nine known β-triketones (311). Woodsianone A is a β-triketone-sesquiterpene adduct and woodsianone B is a β-triketone epoxide derivative. The structures of the new and known compounds were elucidated from the analysis of 1D/2D NMR and MS data. The relative configurations of the compounds were determined from analysis of 1H–1H coupling constants and ROESY correlations. All compounds (111) had antiplasmodial activity against the chloroquine sensitive strain 3D7. The known compound rhodomyrtone (5) and new compound woodsianone B (2) showed moderate antiplasmodial activities against the 3D7 strain (1.84 µM and 3.00 µM, respectively) and chloroquine resistant strain Dd2 (4.00 µM and 2.53 µM, respectively).  相似文献   

6.
The floral organogenesis of Phytolacca dodecandra L′Her. (Phytolaccaceae) has been observed under both scanning electron microscope (SEM) and light microscope. The primordia of the floral appendage are arranged according to a pentamerous pattern and acropetal succession. Five sepal primordia arise in a 2/5 sequence, and no petal primordia have been observed. The stamen primordia arise centrifugally. The first two pairs arise successively opposite sepal one and two. In the subsequent initiation of inner and outer stamens, P. dodecandra differs from other species in the genus Phytolacca. The four or five carpel primordia arise in rapid succession, usually equal in number and alternating with the inner stamens. The effects of temporal and spatial factors during the floral organogenesis of P. dodecandra are discussed. The data on the androecial ontogeny in P. dodecandra refute the existence of diplostemony in Phytolaccaceae, in which P. dodecandra occupies a pivotal systematic position. The androecial ontogeny in P. dodecandra supports the viewpoint that in the genus Phytolacca pentamerous flowers have been derived from trimerous flowers.  相似文献   

7.
《Phytochemistry》1987,26(11):3090-3091
The bark of an Indian medicinal plant, Flacourtia indica, yielded a new phenolic glucoside ester, flacourtin, identified as 3-hydroxy-4-hydroxymeth  相似文献   

8.
《Phytochemistry》1987,26(6):1844-1845
A new flavonoid alkaloid, lilaline, was isolated from the aerial part of Lilium candidum. Its structure has been elucidated as 3,5,7,4′-tetrahydroxy-8-(3-methyl-2-oxo-pyrrolidmyl)flavone.  相似文献   

9.
《Phytochemistry》1986,25(5):1234-1235
A tertiary bicyclic sesquiterpene alcohol has been isolated from Valeriana officinalis, and identified as (−)-pacifigorgiol, the optical antipode of the alcohol isolated from Pacifigorgia adamsii.  相似文献   

10.
11.
The structure of 3, 21, 24 trimethyl-5,7-dihydroxyhentriacontanoic acid δ-lactone, a new δ-lactone, isolated from the flowers of Grewia asiatica has been deduced on the basis of physico-chemical studies.  相似文献   

12.
13.
Summary Polyclonal antibodies directed against polypeptide epitopes of conglutin , a glycosylated lectin in lupin seed, have been used to identify and quantify this protein in root extracts of germinating lupins. The highest conglutin content was found in protein extracts of root elongation zones after 5 to 7 days germination. Root conglutin showed the same subunit composition, glycosylation pattern, isoelectric point, and lectin activity as the cotyledonary one. Immunolocalization experiments on root thin sections demonstrated that conglutin is chiefly present in the intercellular spaces of the cortical parenchyma, where it forms large aggregates. Labelling of the Golgi complexes and the area between the plasmalemma and cell wall revealed the conglutin pathway from post-synthetic processing to excretion via the secretory system.Abbreviations EDTA ethylene diamino tetraacetic acid - IEF isoelectric focusing - LRW London resin white - NC nitrocellulose - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - Pi inorganic phosphate - SDS sodium dodecylsulphate - TEM transmission electron microscopy  相似文献   

14.
Applied Microbiology and Biotechnology - (−)-vibo-Quercitol is a deoxyinositol (1l-1,2,4/3,5-cyclohexanepentol) that naturally occurs in oak species, honeydew honey, wines aged in oak...  相似文献   

15.
A new β-carboline alkaloid, eudistomidin G (1), has been isolated from the Okinawan marine tunicate Eudistoma glaucus, and the structure was elucidated from spectroscopic data. Furthermore, the structure of eudistomidin B (2), which has been isolated from the same tunicate, was revised from 2a to 2b by detailed analyses of spectroscopic data. Asymmetric synthesis of the revised structure (2b) of eudistomidin B (2) and its (1S,10S)-diastereomer (2c) has been accomplished with the Noyori catalytic asymmetric hydrogen-transfer reaction. The absolute configuration of eudistomidin B (2) was confirmed to be 2b possessing (1R,10S)-configuration, from comparison of the 1H NMR data, CD spectra, [α]D values, and HPLC analysis of 2b, 2c, and natural eudistomidin B.  相似文献   

16.
《Phytochemistry》1986,25(2):453-459
The structures of two γ-lactone carboxylic acids from the lichen Pertusaria albescens, (−)-allo-pertusaric acid and (−)dihydropertusaric acid, have been elucidated by spectroscopic and chemical methods. From P. ophthalmiza, taraxerone and a mixture of long chain aliphatic alcohols and fatty acids have been isolated.  相似文献   

17.
In an investigation of (?)-Cercosporamide derivatives with a plasma glucose-lowering effect, we found that N-benzylcarboxamide derivative 4 was a partial agonist of PPARγ. A SAR study of the substituents on carboxamide nitrogen afforded the N-(1-naphthyl)methylcarboxamide derivative 23 as the most potent selective PPARγ modulator. An X-ray crystallography study revealed that compound 23 bounded to the PPARγ ligand binding domain in a unique way without any interaction with helix12. Compound 23 displayed a potent plasma glucose-lowering effect in db/db mice without the undesirable increase in body fluid and heart weight that is typically observed when PPARγ full agonists are administrated.  相似文献   

18.
Nine new spirocyclic acylphloroglucinol derivatives, hyperpatulols A–I (19), were characterized from the flowers of Hypericum patulum. Their structures were elucidated by the basic analysis of the obtained spectroscopic data, and their absolute configurations were assigned by both the electronic circular dichroism (ECD) exciton chirality method and ECD calculation. The evaluation of their anti-migration effects on U2-OS human osteosarcoma cells showed that compound 4 exhibited moderate inhibitory activity in a dose-dependent manner. Further pharmacological studies revealed that 4 could regulate the expression of the proteins Vimentin and E-cadherin.  相似文献   

19.
Relatively little is known about pollination and other aspects of the reproductive biology of bamboos, but wind pollination is assumed to be the rule, at least in woody bamboos. Documenting the reproductive biology of woody bamboos is a complex task due to the long periods of time between flowering cycles, which range from 3 to 120 years. Insects visiting Guadua paniculata and G. inermis flowers were collected in the field. Scanning electron micrographs were taken of the visiting insects. Four species of bees, three from tribe Meliponini (Geotrigona acapulconis, Plebeia frontalis and Trigona fulviventris) and one from tribe Apini (Apis mellifera), along with a syrphid fly (Toxomerus teligera) were found visiting bamboo flowers. Some species of Hemiptera were also found feeding on the flowers, such as Neortholomus jamaicensis (Lygaeidae), or preying on the flower visitors (Apiomerus pictipes (Reduviidae)). Insects visiting bamboo inflorescences may facilitate the release of pollen grains into the air, promoting outcrossing and genetic flow among the individuals of the flowering bamboo populations.  相似文献   

20.
The essential oils from aerial parts of nine populations of Zuccagnia punctata Cav. (Fabaceae) were obtained by hydrodistillation and analyzed by GC–FID, GC–MS and 13C NMR. A total of 80 constituents, mainly oxygenated monoterpenes, were identified representing from 79.0 to 95.2% of the total oils which showed different composition patterns. The unusual compound (?)-5,6-dehydrocamphor, the major constituent in six of the samples investigated with percentages ranging from 12.3% to 56.5%, was isolated for the first time from nature and its structure was completely defined from NMR spectrometric data. Microscope studies of leaves indicated that not only capitate glands but also non-glandular trichomes, not previously described in this species, were present on the leaf surfaces.The essential oil showed antifungal activity against the dermatophytes Microsporum gypseum, Tricophyton rubrum and T. mentagrophytes with MIC values between 15.6 and 125 μg ml?1, being T. rubrum the most susceptible species.  相似文献   

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