Four new glycosides from the seeds of Cassia obtusifolia

Four new glycosides, including one anthraquinone glycoside (1), one naphthalene glycoside (2), and two naphthopyrone glycosides (3–4), with 10 known compounds (5–14) were isolated from the seeds of Cassia obtusifolia L. The new structures were determined by spectroscopic analysis and chemical transformations.     

Germitorosone and methylgermitorosone,two hydroanthracene derivatives from seedlings of Cassia torosa

Two new yellow pigments, germitosone and methylgermitorosone, were isolated from the seedling of Cassia torosa. The structures of these substances were established as 3,7 dimethyl - 6 - methoxy - 1 - oxo - 2,3,8,9 - tetrahydroxy - 1,2,3,4 - tetrahydroanthracene and 6,9 dimethoxy - 3,7 - dimethyl - 1 - oxo - 2,3,8 - trihydroxy - 1,2,3,4 - tetrahydroanthracene respectively.     

Isolation and structural characterization of the water-extractable polysaccharides from Cassia obtusifolia seeds

The seed of Cassia obtusifolia is a food or herbal medicine used for improving eyesight, treating constipation and other disorders, and polysaccharides have been implicated in these pharmacological activities. The endosperm of the seeds, Cassia gum, is a commercial thickening or gelling agent, composed mainly of galactomannans. However, the whole seeds of C. obtusifolia, rather than the endosperm, are used in folk medicine or food, which might contain more complex constituents of polysaccharides. In this study, the whole seeds of C. obtusifolia were extracted with boiling water, and from the water extract, three homogeneous fractions were isolated, designated CFAA-1, CFAA-3, and CFBB2, respectively, after treatment with Fehling solution followed by anion-exchange and gel permeation chromatography. Using chemical and spectroscopic methods, CFAA-1, and CFAA-3 were elucidated to be both branched galactomannans with different molecular weights, consisting of 1,4-linked β-d-mannopyranosyl backbone with single-unit α-d-galactopyranosyl branches attached to O-6 of mannose, while CFBB2 was shown to be a linear (1→4)-α-polygalacturonic acid.     

Dimeric hydroanthracenes from the unripe seeds of Cassia torosa

From the unripe seeds of Cassia torosa three new dimeric hydroanthracene derivatives were isolated along with stigmasterol, sitosterol, campesterol, physcion-9-anthrone, torosachyrsone and the phlegmacins A₂ and B₂. The structures of the new derivatives were established as physcion-10, 10′-bianthrone, anhydrophlegmacin B₂ [2-(6′-methoxy-3′-methyl-3′, 8′, 9′-trihydroxy-1′-oxo-1′, 2′, 3′, 4′-tetrahydroanthracene-10′-yl)-1, 8-dihydroxy-3-methoxy-6-methyl-9-oxo-9, 10-dihydroanthracene] and torosanin [2-(6′-methoxy-3′-methyl-3′, 8′,9′-trihydroxy-1′-oxo-1′, 2′, 3′,4′-tetrahydroanthracene-5′-yl)-1, 8-dihydroxy-3-methoxy-6-methyl-9-oxo-9, 10-dihydroanthracene], respectively.     

Iso-erysopinophorine,a new quaternary alkaloid from the seeds of Erythrina arborescens

The ethanolic extract of the seeds of Erythrina arborescens yielded a new quaternary alkaloid provisionally named as iso-erysopinophorine besides the other alkaloids reported previously. The new alkaloid was characterised by chemical and spectral studies.     

Stereostructures of inunal and isoalloalantolactone,two biologically active sesquiterpene lactones from Inula racemosa

Two new sesquiterpene lactones, inunal and isoalloalantolactone, have been isolated from Inula racemosa. Inunal, an aldehydolactone, displays considerable biological activity as a plant growth regulator. Structures have been assigned to these compounds on the basis of spectral data and chemical correlation with alantolactone and isotelekin.     

The flavonoids of Cassia renigera stem bark

A new flavanone glycoside 5-hydroxy-6,7,3′,4′,5′-pentamethoxyflavanone 5-O-α-l-rhamnopyranoside along with quercetagetin 3,6-dimethyl ether and an anthraquinone glycoside have been isolated from the stem bark of Cassia renigera. The two flavonoids were characterized by spectral and chemical studies.     

Tetrahydrolathyrine: A new amino acid from seeds of Lonchocarpus costaricensis

A new non-protein amino acid, tetrahydrolathyrine (2(S)-3(2-amino-1,4,5,6- tetrahydropyrimidin-4-yl)alanine), has been isolated from seeds of Lonchocarpus costaricensis.     

Sesquiterpene lactones of Artemisia: TLC analysis and taxonomic significance

Samples of Artemisia arbuscula ssp. arbuscula, A. tridentata ssp. tridentata, ssp. wyomingensis, ssp. vaseyana and ssp. vaseyana f. spiciformis were collected from various locations in Montana and analyzed by TLC for their sesquiterpene lactone content. Artemisia tridentata ssp. tridentata and ssp. wyomingensis are distinct morphologically and chemically, whereas ssp. vaseyana has three distinct chemical groups not yet separated morphologically. Artemisia arbuscula ssp. arbuscula and A. tridentata ssp. vaseyana f. spiciformis are easily separated by morphology but have identical TLC patterns. It has been further shown that the sesquiterpene lactones produced for a particular species or subspecies are the same regardless of the time of the year collected, although the quantity varies from winter to summer.     

Effects of hematin and carbon monoxide on the salinity stress responses of Cassia obtusifolia L. seeds and seedlings

Aims

The purpose of the present study was to investigate the mechanism of carbon monoxide (CO) and hematin in alleviating the inhibition of Cassia obtusifolia seeds and seedlings. NaCl (100?mM) was used to mimic salinity stress in a series of experiments.

Methods

Varying combinations of CO in a saturated aqueous solution and hematin (1.0?μM) were added to seeds and seedlings under salinity stress. Seed germination indices and seedling parameters were investigated.

Results

Seed germination and seedling growth were significantly inhibited under salinity stress. NaCl-induced inhibitory effects on seed germination and seedling growth were ameliorated by hematin or the CO aqueous solution. Addition of 1.0?μM hematin or 5?% CO-saturated aqueous solution to seeds and seedlings significantly alleviated damage to the plant cells under salinity stress. Hematin and the CO aqueous solution enhanced chlorophyll concentration, total soluble sugars, free proline, and soluble protein, and improved photosystem II (PSII) photochemical efficiency levels, PSII actual photochemical efficiency, and the photochemical quench coefficient. In contrast, the non-photochemical quenching coefficient decreased. Hematin and the CO aqueous solution also enhanced the activities of superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and glutathione reductase, thus alleviating oxidative damage, as indicated by decreases in hiobarbituric acid reactive substances, hydrogen peroxide concentration, relative conductivity, and lipoxygenase activity. Heme oxygenase (HO) activity was increased by hematin treatment. Hematin may contribute to endogenous HO-derived CO, since the addition of zinc protoporphyrin IX or hemoglobin reversed the protective effects conferred by hematin specified above.

Conclusions

Based on the experimental results, we conclude that hematin and CO induce advantageous effects on the attenuation of salt-stress inhibition of C. obtusifolia seeds and seedlings and alleviate oxidative damage by conferring beneficial cytoprotection and activating anti-oxidant enzymes.     

Phlegmacins and anhydrophlegmacinquinones: Dimeric hydroanthracenes from seedlings of Cassia torosa

From seedlings of Cassia torosa four dimeric hydroanthracenes have been isolated. Two, a pair of atropisomeric dimers consisting of two molecules o     

Six new cassane diterpenoids from the seeds of Caesalpinia sappan

Six new cassane diterpenoids (1–6) and 15 known compounds were isolated and identified from the seeds of Caesalpinia sappan. The structures of the new compounds were determined based on the spectroscopic methods, including 1D and 2D NMR techniques. Compound 1 is a rare cassane diterpenoid featuring a nitrogen containing bridge between C-19 and C-20. Compounds 1 and 2 exhibited moderate cytotoxicity against HCT116, AGS, and HepG2 cell lines with IC₅₀ values ranging from 6.36 to 27.86 μM.     

Fenugreekine,a new steroidal sapogenin-peptide ester of Trigonella foenum-graecum

A new C₂₇-steroidal sapogenin-peptide ester, fenugreekine, has been isolated from seeds of Trigonella foenum-graecum. On acid hydrolysis, it afforded diosgenin, yamogenin, (25R)-spirosta-3,5-diene, a mixture of three isomeric (2S,3R,4R-, 2S,3R,4S-, 2S,3S,4R-)-4-hydroxyisoleucine lactones, 4′-hydroxyisoleucyl-4-hydroxyisoleucine lactone, and a C₁₄-dipeptide which was partially characterized. On the basis of this chemical transformation and spectral (UV, IR, PMR, MS) evidence of fenugreekine and its transformation products, the steroidal sapogenin-peptide ester is assigned structure (1). The two dipeptides also have not been encountered before in nature or prepared synthetically. The compound shows a number of interesting pharmacological and virological activities.