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1.
From the dried roots of Panax ginseng two new minor dammarane saponins named koryoginsenoside-R1 and -R2 were isolated, along with fourteen known saponins. On the basis of spectral and chemical evidence, the structure of the new saponins were elucidated as 6-O-[trans butenoyl-(1-->6)-beta-D-glucopyranosyl]-20-O-beta-D- glucopyranosyl dammar-24-en-3 beta,6 alpha,12 beta,20(S)-tetrol and 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D- glucopyranosyl-(1-->6)-beta-D-glucopyranosyl] dammar-22-en-3 beta,12 beta, 20(S),- 25-tetrol, respectively.  相似文献   

2.
The methanol extract of the whole plant of Sansevieria trifasciata has yielded 12 steroidal saponins, 10 of which are new constituents. The respective structures of the new compounds have been shown by the spectroscopic evidence, and alkaline- and acid-catalysed degradation. This is the first report of the isolation of steroidal saponins from S. trifasciata.  相似文献   

3.
Extraction of the roots of Baptisia australis afforded a new triterpenoid saponin, baptisiasaponin I together with kaikasaponin III. The structure of baptisiasaponin I was elucidated as 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranosyl- (1-->2)-beta-D-glucuronopyranosyl sophoradiol on the basis of its spectral data and chemical degradation.  相似文献   

4.
Four novel triterpenoid saponins were isolated from the seeds of Vaccaria segetalis. Their structures were established as vaccaroside A, gypsogenic acid-28-O-beta-D- glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6)-[beta-D- glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; vaccaroside B, gypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->2)-[3-hydroxyl-3- methylglutaroyl-(1-->6)]-beta-D-glucopyranosyl-(1-->6)-[beta-D- glucopyranosyl-(1-->3)]-beta-D-glucopyranoside; vaccaroside C, 23-O-beta-D-glucopyranosyl-gypsogenic acid-28-O-beta-D- glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->6)- [beta-D-glucopyranosyl-(1-->3)]-beta-D-glucopyranoside and vaccaroside D, 3,4-secogypsogenic acid-28-O-beta-D-glucopyranosyl-(1-->3)- [beta-D-glucopyranosyl-(1-->6)]-beta-D-glucopyranoside by a combination of extensive NMR (DEPT, COSY, HOHAHA, HETCOR, HMBC and NOESY) studies and chemical degradation.  相似文献   

5.
A new steroidal saponin, dumoside, characterized as (20S)-3 beta, 16 beta-dihydroxy pregn-5-ene-22-carboxylic acid (22, 16)-lactone-3-O-beta-chacotrioside, was isolated from the whole plant of Asparagus dumosus Baker and the structure was deduced from spectral data. In addition to dumoside three more steroidal saponins characterized as 3 beta-dihydroxy pregn-5,16-dien-20-one 3-O-beta-chacotrioside, 3 beta, 22 alpha, 26-trihydroxyfurost-5-ene-3-O-beta-chacotrioside-26-O- beta-D-glucopyranoside and its corresponding 22 alpha-O methoxy analogue were also isolated for the first time from this source. The structures have been identified with the help of FAB-MS, 1H NMR, 13C NMR and extensive 2D NMR spectroscopy, as well as comparison with reported spectroscopic data.  相似文献   

6.
Four dammarane-type saponins were isolated by means of centrifugal partition chromatography from the root bark of Zizyphus lotus. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy. One of these glycosides is the known jujuboside A. The others are three new dammarane saponins, identified as 3-O-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl (1-->3)-[alpha-L-rhamnopyranosyl(1-->2)]-alpha-L-arabinopyranosyl jujubogenin = jujuboside C, 3-O-alpha-L-rhamnopyranosyl (1-->2)-[beta-D-glucopyranosyl(1-->3)]-beta-D-galactopyranosyl lotogenin = lotoside I, and 3-O-alpha-L-rhamnopyranosyl(1-->2)-[beta-D-glucopyranosyl (1-->3)]-beta-D-glucopyranosyl lotogenin = lotoside II. Lotogenin is a new dammarane derivative identified as (15R, 16R, 20R, 22R)-16 beta, 22-epoxydammar-24-ene-3 beta, 15 alpha, 16 alpha, 20 beta-tetraol.  相似文献   

7.
Three new triterpenoid saponins were isolated from the roots of Gypsophila oldhamiana. Their structures were elucidated, using a combination of homonuclear and heteronuclear 2D nmr and fabms, as 3-0-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranolyl-(1-->3)] -beta-D-glucuronopyranosyl quillaic acid methyl ester [1], 3-0-beta-D-galactopyranosyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3)]-beta- D-glucuronopyranosyl gypsogenin methyl ester [2], and 3-0-beta-D-galactopyranolsyl-(1-->2)-[beta-D-xylopyranosyl-(1-->3) ]-beta-D-glucuronopyranosyl quillaic acid 28-[0-beta-D-fucopyranosyl(1-->4)-beta-D-glucopyranosyl(1-->3)]-alpha-L- rhamnopyranosyl] ester.  相似文献   

8.
Three new triterpenoid saponins, latifolosides F, G, H were isolated from the leaves of Ilex latifolia. Their structures were elucidated on the basis of chemical and spectral evidence. Latifoloside F was determined to be 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl ilexgenin B 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside. Latifoloside G was 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl pomolic acid 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside. Latifolioside H(3) was 3-O-[alpha-L-rhamnopyranosyl(1-2)]-[beta-D-glucopyranosyl(1-3)-]- alpha-L-arabinopyranosyl siaresinolic acid 28-O-[alpha-L-rhamnopyranosyl(1-2)]-beta-D-glucopyranoside.  相似文献   

9.
Two new saponins were isolated as the major components of the deacylated saponin extract from the underground parts of Celmisia spectabilis. Their structures were established by NMR and mass spectral data and derivative formation as 2 beta,3 beta,17,23- tetrahydroxy-28-norolean-12-en-16-one-3-O-alpha-L-arabinopyrano syl (1-->2)-alpha-L-arabinopyranosyl(1-->6)-beta-D-glucopyranoside and 2 beta,3 beta,17,23- tetrahydroxy-28-norolean-12-en-16-one-3-O-alpha-L-arabinopyrano syl (1-->2)-alpha-L-arabinopyranosyl(1-->6)-[alpha-L-rhamnopyranosyl (1-->2)]-beta-D-glucopyranoside.  相似文献   

10.
Uropontin is the urinary form of osteopontin, an aspartic acid-rich phosphorylated glycoprotein. Uropontin has been previously shown to be a potent inhibitor of the nucleation, growth and aggregation of calcium oxalate crystals and the binding of these crystals to renal epithelial cells. Quantitative data defining the excretion of this protein are necessary to determine its role in urinary stone formation. In the present studies, we determined uropontin excretion rates of normal humans. Urine samples were obtained under conditions of known dietary intake from young adult human volunteers with no history, radiographic or laboratory evidence of renal disease. Urinary concentrations of uropontin were measured by a sensitive ELISA employing an affinity purified polyclonal antiserum to uropontin. Thirteen normal subjects ingested a constant diet providing 1 gram of calcium, 1 gram of phosphorus, 150 mEq of sodium and 1 gram of protein per kilogram of body wt per day during an eight day study period. The relationship of urinary volume to uropontin excretion was assessed by varying fluid intake on the last four days of the study to change the mean urine volume/24 hr by > 500 ml. Urine collected in six hour aliquots for eight days was analyzed for uropontin by ELISA, and for calcium, and creatinine. Daily uropontin excretion of 13 individual subjects was 3805 +/- 1805 micrograms/24 hr (mean +/- 1 SD). The mean urinary levels (1.9 micrograms/ml) detected in the present study are sufficient for inhibition of crystallization; our previous studies have demonstrated that the nucleation, growth and aggregation of calcium oxalate crystals and their binding to renal cells in vitro are inhibited by this concentration of purified uropontin. In contrast to the regular pattern of diurnal variation of calcium excretion seen in most subjects, uropontin excretion showed no regularity of diurnal variation and was not directly related to either calcium or creatinine excretion or changes in urinary volume. However, uropontin concentration varied inversely with urine volume (P < or = 0.001), so that the highest uropontin concentrations occurred when urine volume was the lowest. We conclude that the physiologic characteristic of an inverse relationship of uropontin concentration to urine volume favors protection from urinary crystallization of calcium oxalate by uropontin. Our quantitative definition of urinary uropontin excretion of normal adults provides the basis for the evaluation of uropontin excretion by individuals who have formed urinary stones.  相似文献   

11.
A novel triterpene, viburgenin (1), has been isolated from an extract of the ripe fruit rinds of Rudgea viburnioides, together with the known saponins, arjunglucoside I and trachelosperosides B-1 and E-1, and the triterpenes trachelosperogenin B (2) and arjungenin. Compound 2 was previously obtained as a product from enzymatic hydrolysis, and it is reported for the first time as a natural product. The structure of compound 1 was determined as 2alpha,3beta, 19alpha,23,24-pentahydroxyurs-12-ene by extensive use of 1D and 2D NMR spectroscopic methods. Compound 1 exhibited moderate antifungal activity against Cladosporium cladosporioides.  相似文献   

12.
Two new pyrrole alkaloids, solsodomine A and B, were isolated from the fresh berries of Solanum sodomaeum L., collected from the Libyan desert. The structures of these compounds were established by 2D-NMR, including 15N NMR spectroscopy and chemical degradation. Solsodomine A (1) shows activity against Mycobacterium intracellulare. This is the first report of pyrrole alkaloids from the genus Solanum.  相似文献   

13.
Triterpenes and triterpenoid saponins from Mussaenda pubescens   总被引:1,自引:0,他引:1  
Two novel triterpenoid saponins, named mussaendosides U and V, together with one known saponin and four known triterpenes were isolated from the aerial parts of Mussaenda pubescens (Rubiaceae). The structures were determined on the basis of chemical analysis ad spectral methods. All these compounds were identified for the first time from the genus Mussaenda.  相似文献   

14.
When two species have predators in common, animals might be able to obtain important information about predation risk from the alarm calls produced by the other species. The behavioural responses of adult yellow-bellied marmots, Marmota flaviventris, and golden-mantled ground squirrels, Spermophilus lateralis, to conspecific and heterospecific alarm calls were studied to determine whether interspecific call recognition occurs in sympatric species that rarely interact. In a crossed design, marmot and squirrel alarm calls were broadcast to individuals of both species, using the song of a sympatric bird as a control. Individuals of both species responded similarly to conspecific and heterospecific anti-predator calls, and distinguished both types of alarms from the bird song. These results indicate that both marmots and squirrels recognized not only their own species' anti-predator vocalizations, but also the alarm calls of another species, and that these vocalizations were discriminated from an equally loud non-threatening sound. These findings suggest that researchers ought to think broadly when considering the sources of information available to animals in their natural environment. Copyright 1998 The Association for the Study of Animal Behaviour Copyright 1998 The Association for the Study of Animal Behaviour.  相似文献   

15.
16.
Corticosteroids were withdrawn from the immunosuppressive regimen of 168/197 (85%) of liver transplant patients who survived for more than three months. In 14, steroids were restarted for reasons other than rejection. The remaining 154 patients were evaluated for the occurrence of rejection and graft loss. Risk factors for the development of rejection after steroid withdrawal were assessed. There were 13 episodes of rejection in 12 (7.8%) grafts; 7 (4.5%) experienced acute cellular rejection, and 6 (3.9%) developed chronic ductopenic rejection. All cases of acute rejection resolved with high-dose steroids. Graft and patient loss due to chronic rejection was 3 (1.9%) and 2 (1.3%), respectively. Chronic rejection resolved in 1 patient, 1 was successfully retransplanted, and in the other 2 the principal cause of death was recurrent tumor. None of the risk factors examined (primary indication for transplant, severity of previous acute rejection, use of OKT3, retransplantation, ABO blood group donor/recipient match, CMV infection, and CsA mono versus CsA and AZA double therapy) were associated with the development of chronic rejection poststeroid withdrawal. The prevalence of side effects, after steroid withdrawal, was low; 66% of patients never required antihypertensive medication; 14% experienced a significant septic episode, and only 4 died with sepsis as the major factor. There were no fungal sepsis and no new cases of diabetes. Withdrawal of corticosteroids after 3 months can be successfully achieved in the majority of liver allograft recipients and is associated with a low rate of rejection, graft loss, and complications attributable to immunosuppressive medication.  相似文献   

17.
A two-part study was conducted to determine the sources of variation in nasalance scores derived from the Nasometer. In Study #1, a function generator was used as a signal source to calibrate and input sine and square waves directly into the Nasometer. Ten stimuli ranging from 105 to 330 Hz in 25 Hz increments were evaluated. In Study #2, the same signal source and an amplified loudspeaker were used to calibrate and present square waves to the nasometer via five different sets of microphones. The sound pressure level of all stimuli was maintained at 88 dB. Each microphone set was calibrated using the 105 Hz signals. Results from Study #1 indicated consistent nasalance scores across all frequencies (i.e., all scores were within 2% of calibration). Results from Study #2 demonstrated deviations greater than 2% from calibration as a function of frequency for all five sets of microphones. The smallest deviation was 5%, whereas the largest deviation was 14%. We suggest that the variation in nasalance as a function of stimulus frequency may be due to a mismatch in the sensitivity of microphones (i.e., different frequency response characteristics). It is further suggested (a) that individual investigators determine the response characteristics of their microphones and (b) that relatively small variations in nasalance scores (i.e., 5-14%) either within or across speakers be interpreted with caution.  相似文献   

18.
Solakhasoside (1), a novel steroidal saponin, was isolated from the fruit of Solanum khasianum. Its structure was determined as (23S, 25S)-spirot-5-en-3beta,17alpha, 23-triol-3-O-[alpha-L-rhamnopyranosyl-(1-->2)[beta-D-xylopyranosyl-(1 -->3)]-beta-D-galactopyranoside] (1) by spectroscopic analysis.  相似文献   

19.
A new iridoid ester glycoside acylated with p-coumaric acid was isolated from the flowers of Verbascum phlomoides, together with one known one, specioside. Caffeic acid esters, verbascoside and forsythoside B were found as minor constituents. A new saponin was also obtained and identified as desrhamnosylverbascosaponin.  相似文献   

20.
Pharmacologic intervention in the management of allergic conjunctivitis was evaluated with different topical ocular agents in man. Their effect can be precisely assessed with the conjunctival provocation test (CPT). A potent specific H1-receptor antagonist, 0.05% mequitazine eye-drops, was tested in a double-blind randomized, placebo-controlled study using CPT with grass pollen allergens. Twenty healthy subjects allergic to grass pollen were included outside the pollen season after a positive CPT screening. They received one drop of 0.05% mequitazine in one eye and the vehicle in the contralateral eye in a random order, four times daily for 5 days. CPT was performed 15 min after the last instillation, and the threshold dose inducing a positive reaction was determined. Results were given by Abelson's composite score including redness, chemosis, tearing, and itching. Topical 0.05% mequitazine significantly reduced the composite score compared to placebo. The allergen threshold concentration which induced the positive conjunctival reaction was higher in mequitazine pretreated eyes. No side-effect was reported. These data clearly suggest that mequitazine has potential to treat allergic conjunctivitis.  相似文献   

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