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1.
Six new lanostane triterpenes, artabotryols A, B, C1, C2, D, and E ( 1, 2, 3a, 3b, 4 , and 5 , resp.) have been isolated from the seeds of Artabotrys odoratissimus (Annonaceae). Their structures have been established as (3α,22S,25R)‐3‐hydroxy‐22,26‐epoxylanost‐8‐en‐26‐one ( 1 ), (3α,22S,25R)‐22,26‐epoxylanost‐8‐ene‐3,26‐diol ( 2 ), (3α,22S,25R,26R)‐26‐methoxy‐22,26‐epoxylanost‐8‐en‐3‐ol ( 3a ), (3α,22S,25R, 26S)‐26‐methoxy‐22,26‐epoxylanost‐8‐en‐3‐ol ( 3b ), (3α,22S,25R)‐3,22‐dihydroxylanost‐8‐en‐26‐oic acid ( 4 ) and (3α,7α,11α,22S,25R)‐3,7,11‐trihydroxy‐22,26‐epoxylanost‐8‐en‐26‐one ( 5 ) by spectroscopic studies and chemical correlations.  相似文献   
2.
Chloroform extract of bark of Artabotrys crassifolius Hook.f. & Thomson exhibited antibacterial activities against both American Type Culture Collection and clinical bacterial strains in vitro with zones of inhibition ranging from 7 to 14 mm. Further analysis of this extract yielded artabotrine, liridine, lysicamine and atherospermidine. Artabotrine displayed a broad array of antibacterial activity mostly against Gram-positive bacteria with minimum inhibitory concentration (MIC) values ranging from 1.25 μg/mL to 5 μg/mL. Of note, artabotrine, liridine and lysicamine are bactericidal against Gram-negative extended-spectrum beta-lactamase-producing Klebsiella with MIC values equal 2.5, 2.5 and 10 μg/mL, respectively, and minimum bactericidal concentrations values equal to 2.5, 5 and 20 μg/mL.  相似文献   
3.
A new polyoxygenated cyclohexene derivative, artahainanol A (1), together with three known analogues (24), was isolated from the stems and leaves of Artabotrys hainanensis. Among them, 1 is an unusual polyoxygenated cyclohexene containing 14 carbon atoms on the carbon skeleton. All known compounds (24) were isolated from the genus Artabotrys for the first time. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 14 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 2.68 to 18.32 μM.  相似文献   
4.
The Annonaccac family is a main one of the tropical plants flora and there are totally 127 genus, about 2231 species in the world, wildly distributed in the tropical zone and subtropics areas.China is one of the countries where species of this family are mostly distributed, with 24 genus, 103 species and 6 variant, among which, 45 species and 1 variant are endemic to China. There are about 100 types of plants of Artabotrys genus in the world, among which, 10 species are in China. Scholars from home and abroad have found a series of new substance of biological activities in the plants of Annonaccac family with antimalarial, anti-tumor, anti-leukemia and obvious cardiotonic effects,which has aroused great interest. Plants of Artabotrys genus, Artabotrys Hainanensis are endemic to Hainan, distributed widely in Hainan Island. They have long been used among the ordinary people as medicinal plants with antipyretic, antidotal, antiphlogistic and analgesic effects. The flavonoid is a very important secondary metabolite in plants with many physiological activities such as fat-reduction, antithrombus, antioxidant and blood-sugar-reduction. This paper studies the total flavonoids from stem and leaf of Artabotrys by spectrophotometry. Artabotrys Hainanensis R.E.Fries were collected from Hainan Jianfeng Mountain and were identified. Spectrophotometry was used to determination of the total flavonoids from stem and leaf of Artabotrys. The total flavonoids of Artabotrys were tested with rutin as check sample. By adding aluminium ion agent and controling proper pH, the flavonoids and the aluminium ion were combined into complex compound and the characteristic absorption peak was obtainable in the visible spectrum. The total flavonoids from stem and leaf of Artabotrys were determined to be 2.29% in stem and 6.83% in leaf. The regression equation was Y=0.000786A+0.0058, and the correlation coefficient r=0.9997. This method is easily operated and the result determined is stable and accurate.  相似文献   
5.
Artabotrys Hainanensis R.E. Fries are plants of the Annonaccac family artabotrys genus,which includes an estimated 100 types of plants distributed mainly in the tropical zone and the subtropics areas. Four types of the plants are discovered in our country, two of which, A.Hongkongensis Hance and A. hexapetalus (Linn. F.) Bhandari, in Guangdong Province, and the other two, A. Pilosus and A. Hainanensis R.E. Fries, in Hainan Province. The latter are widely distributed in Hainan Island with very rich reserves. They have long been used among the ordinary people as medicinal plants with antipyretic, antidotal, antiphlogistic and analgesic effects and are often used for malaria. Scholars from home and abroad have paid much attention to the plants of the Annonaccac family for their containing anti-tumor activities, and after early or late research of the chemical constituents of the root, stem (derm), leaf and fruit of many types of plants of Artabotrys genus, more than 40 compounds including alkaloid, flavone and terpenoid have been isolated and obtained. Artabotrys Hainanensis R.E. Fries are Hainan endemic plants and there has been no report on the research of their chemical constituents and biological activities so far. In order to find new constituents of pharmacologic activity, we have researched the chemical constituents of the leaf and stem.The crude drugs were collected from Hainan Jianfeng Mountain and were identified as Artabotrys Hainanensis R.E. Fries of the Annonaccac family artabotrys genus. Its sample specimen is now kept in Chemistry Department of Hainan Normal University.After isolation and identification of constituent, six compounds were isolated from the leaf of Artabotrys Hainanensis R.E. Fries and elucidated as β -sitosterol (Ⅰ), catechin (Ⅱ), mangiferin (Ⅲ),(Ⅳ), (Ⅴ), (Ⅵ). All the compounds were obtained from this plant for the first time. Compounds Ⅱ, Ⅲ,Ⅳ, Ⅴ and Ⅵ were obtained from the genus of Artabotrys for the first time.  相似文献   
6.
Abstract

A new naturally occurring trinoreudesmane sesquiterpene, artahongkongol A (1), together with seven known eudesmane sesquiterpenes (2?8), was isolated from the stems and leaves of Artabotrys hongkongensis Hance. Among them, 1 is a rare trinoreudesmane sesquiterpene containing 12 carbon atoms on the carbon skeleton. All known compounds (2?8) were isolated from the genus Artabotrys for the first time. The structure of 1 was elucidated by extensive spectroscopic methods and the known compounds were identified by comparisons with data reported in the literature. All isolated compounds were evaluated for their cytotoxicities against five human cancer cell lines: HL-60, SMMC-7721, A-549, MCF-7 and SW480 in vitro. Compounds 1?8 showed significant inhibitory effects against various human cancer cell lines with IC50 values ranging from 0.57 to 15.68?μM.  相似文献   
7.
山绿茶化学成分的研究   总被引:2,自引:0,他引:2  
硅胶柱色谱、凝胶柱色谱分离,高效液相色谱纯化,得到单体化合物,用各种有机波谱鉴定化合物结构。分离得到6个化合物,鉴定为:α-香树脂素(Ⅰ),乌索酸(Ⅱ),3β,19α-二羟基乌索-12-烯-24,28-二酸(Ⅳ),2α,3β,23-三羟基乌索-12-烯-28-羧酸(),3β,19α,20β-三羟基乌索-12-烯-24,28-二羧酸(V),3β,19α-二羟基乌索-12-烯-23,28-二羧酸(Ⅲ)。化合物Ⅰ,Ⅲ,Ⅳ,Ⅴ,Ⅵ都是首次从该植物中分离得到。  相似文献   
8.
The purpose of this work was to evaluate chemical constituents, antioxidant and antimicrobial activities of Artabotrys hildebrandtii, an endemic medicinal plant from Madagascar. Ethanol extracts from the leaves and stem bark were tested to evaluate DPPH free radical scavenging, using butylated hydroxytoluene and quercetin as standard antioxidants. An high-performance liquid chromatography/mass spectrometry method was developed to investigate the presence of phenolic compounds in the studied samples; gentisic acid, chlorogenic acid, hyperoside, isoquercitrin, rutin, quercitrin, quercetol, apigenin and luteolin were identified. Total polyphenolic content was determined by a spectrophotometric method using Folin–Ciocâlteu reagent. Results showed the efficiency of A. hildebrandtii leaves extract against strains of Staphylococcus aureus and Listeria monocytogenes, as the inhibitory activity is more powerful compared to Gentamicin, used as the standard drug. The leaves of A. hildebrandtii can be considered an important source of polyphenols, especially of rutin, with good antioxidant and antimicrobial activities.  相似文献   
9.
The medicinal plant Artabotrys hexapetalus (synonyms: A. uncinatus and A. odoratissimus) is known as yingzhao in Chinese. Extracts of the plant have long been used in Asian folk medicine to treat various symptoms and diseases, including fevers, microbial infections, ulcers, hepatic disorders and other health problems. In particular, extracts from the roots and fruits of the plant are used for treating malaria. Numerous bioactive natural products have been isolated from the plant, mainly aporphine (artabonatines, artacinatine) and benzylisoquinoline (hexapetalines) alkaloids, terpenoids (artaboterpenoids), flavonoids (artabotrysides), butanolides (uncinine, artapetalins) and a small series of endoperoxides known as yingzhaosu A-to-D. These natural products confer antioxidant, anti-inflammatory and antiproliferative properties to the plant extracts. The lead compound yingzhaosu A displays marked activities against the malaria parasites Plasmodium falciparum and P. berghei. Total syntheses have been developed to access yingzhaosu compounds and analogues, such as the potent compound C14-epi-yingzhaosu A and simpler molecules with a dioxane unit. The mechanism of action of yingzhaosu A points to an iron(II)-induced degradation leading to the formation of two alkylating species, an unsaturated ketone and a cyclohexyl radical, which can then react with vital parasitic proteins. A bioreductive activation of yingzhaosu A endoperoxide can also occur with the heme iron complex. The mechanism of action of yingzhaosu endoperoxides is discussed, to promote further chemical and pharmacological studies of these neglected, but highly interesting bioactive compounds. Yingzhaosu A/C represent useful templates for designing novel antimalarial drugs.  相似文献   
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