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1.
A moderately thermophilic actinomycete strain, which was identified as Thermoactinomyces strain TA66-2, was isolated from hot-spring water. Fermentation, followed by solvent partition and chromatographic separations, resulted in the isolation of two new and two known molecules. The structures of the new compounds were elucidated as 2-(1-Propionylaminoethyl)thiazole-4-carboxylic acid [2-(1H-indol-3-yl)ethyl]amide and 2-(1-Acetylaminoethyl)thiazole-4-carboxylic acid [2-(1H-indol-3-yl)-ethyl]amide by using spectral methods (1D-, 2D-NMR and LC-ESI-MS).  相似文献   

2.
Triterpenoid saponins from the seeds of Pharbitis nil   总被引:1,自引:0,他引:1  
From the seeds of Pharbitis nil (Convolvulaceae), two new oleanene-type triterpene glycosides, pharbitosides A (1) and B (2), together with beta-sitosterol, beta-sitosterol glucoside (daucosterol), caffeic acid, and methyl caffeate were isolated. The structure of pharbitoside A (1) was elucidated to be queretaroic acid 3-O-alpha-L-rhamnopyranosyl-(1-->2)-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside (1). Pharbitoside B (2) is a 21alpha-hydroxyoleanolic acid saponin carrying the same sugar moiety as that of pharbitoside A (1).  相似文献   

3.
Three pentacyclic triterpenoids including one new guajavanoic acid (2) and two known obtusinin (1) and goreishic acid I (3) have been isolated from the leaves of Psidium guajava. The new constituent 2 has been characterized as 2alpha-hydroxy-3beta-p-E-coumaroyloxyurs-12, 18-dien-28-oic acid through 1H-NMR and 13C-NMR (broad band and DEPT). This is the first report of isolation of compound 1 and 3 from the genus Psidium.  相似文献   

4.
Bioassay-guided fractionation allowed the isolation of two new cytotoxic ent-kaurene diterpenoids, licamichauxiioic-A and -B acids (1 and 2) from the root extract of Licania michauxii Prance (Chrysobalanaceae). They were characterized as ent-15-oxo-9(11),16-kauradien-19-oic acid (1) and ent-15-oxo-13(14),16-kauradien-19-oic acid (2) by various spectroscopic methods, in particular, 1D and 2D NMR spectra, and chemical evidence.  相似文献   

5.
Two new pentacyclic triterpenoids, 3alpha, 30-dihydroxylup-20(29)-en-27-oic acid (1) and (20S)-3alpha, 29-dihydroxylupan-27-oic acid (2) were isolated from the whole herbs of Potentilla discolor Bunge. The structures of these two new compounds were elucidated, and complete assignments of the (1)H and (13)C NMR spectroscopic data were achieved by 1D and 2D NMR experiments (HSQC, HMBC, (1)H-(1)HCOSY and ROESY).  相似文献   

6.
Ursolic acid (1) and kaempferol (3) are two major constituents of the Mediterranean plant Nerium oleander L. Microbial metabolism of (1) with Aspergillus flavus (ATCC 9170) resulted in the formation of 3-oxo-ursolic acid derivative, ursonic acid (2). On the other hand, Cunninghamella blakesleeana (ATCC 8688A) was able to convert (3) into kaempferol 3-O-beta-D-glucopyranoside (4) as well as the new natural product kaempferol 4'-sulfate (5). Incubation of kaempferol with Mucor ramannianus (ATCC 9628) led to the isolation of one metabolite identified as kaempferol 4'-O-alpha-L-rhamnopyranoside (6). Transformation of kaempferol to the new compound kaempferol 7-O-beta-D-4-O-methylglucopyranoside (7) and herbacetin 8-O-beta-D-glucopyranoside (8) was observed after fermentation with Beauveria bassiana (ATCC 13144). Cytotoxic as well as antioxidant activities of the isolated metabolites were determined.  相似文献   

7.
Three new triterpene saponins from the seeds of Aesculus chinensis   总被引:5,自引:0,他引:5  
Three new triterpenoid saponins were isolated from the seeds of Aesculus chinensis, and characterized as 22-tigloylprotoaescigenin 3-O-[beta-D-glucopyranosyl (1-->2)] [beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranosiduronic acid (escin IVg, 1), 22-angeloylprotoaescigenin 3-O-[beta-D-glucopyranosyl (1-->2)] [beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranosiduronic acid (escin IVh, 2) and 16-angeloyl-21-acetylprotoaescigenin 3-O-[beta-D-glucopyranosyl (1-->2)] [beta-D-glucopyranosyl (1-->4)]-beta-D-glucopyranosiduronic acid (escin VIb, 3), together with two known compounds, escin IIIa (4) and desacylescin 1 (5). Their structures were established on the basis of spectroscopic and chemical evidence.  相似文献   

8.
From the roots of Saliva caespitosa Montbret and Aucher ex. Bentham a new diterpene 6beta-hydroxyisopimaric acid (1) has been isolated together with four known diterpenes, one new triterpenoid, 3-acetylvergatic acid (2), as well as five known triterpenoids, two steroids and a flavone. The structures of the compounds were established by spectroscopic analyses. The isolated compounds were tested against standard bacterial strains. Only the new diterpene, 6beta-hydroxyisopimaric acid has strong activity (MIC 9 microg/ml) against S. aureus and (MIC 18 microg/ml) against S. epidermidis as well as against B. subtilis (MIC 9 microg/ml).  相似文献   

9.
山芝麻 (Helicteresangustifolia L inn.)是梧桐科 (Sterculiaceae)山芝麻属植物 ,主要分布在广东、广西、云南及长江以南各省 ,用以治疗感冒发热、麻疹、疟疾和疔疮等症 [1] .王明时等 [2 ,3]曾从该植物中分离出 3个三萜类化合物和 1个萘醌化合物 .为进一步寻找有效成分 ,我们从山芝麻中又分离到 2个新的三萜化合物 1和 2 ,用波谱方法测定了其化学结构 .1 实验部分1 .1 仪器与材料 北京泰克仪器公司的双目镜 X-6型显微熔点仪 ;EQUINOX-55(Bruker)红外光谱仪 ;Varian Unity INOVA 50 0型核磁共振仪 (TMS为内标 ) ;VG Autospec-…  相似文献   

10.
A new phenolic ester 2-( p-hydroxyphenyl)ethyl eicosaheptanoic acid ester (1) and a known one hexacosylferulate (2) were isolated from the acetone extract of Salvia microphylla. In addition, two sesquiterpenes beta-eudesmol (3) and 8alpha-hydroxy-beta-eudesmol (4), a diterpene carnosic acid 12-methyl ether (12-methoxycarnosic acid) (5), three triterpenes erithrodiol 3-acetate, oleanolic acid, lupeol and beta-sitosterol were obtained as known compounds from this plant extract. The structures of the isolated compounds were elucidated by spectroscopic methods, including one- and two- dimensional 1H- and 13C-NMR and MS spectroscopies. The selected compounds were tested for antimicrobial activity against standard bacterial strains, and only carnosic acid 12-methyl ether showed antimicrobial activity against S. aureus at 78 microg mL(-1).  相似文献   

11.
A new minor polyoxygenated triterpene named glutinolic acid (1) and two new aeginetic acid quinovosides (2, 3) were isolated from the roots of Rehmannia glutinosa LIBOSCH. (Scrophulariaceae) cultivated in Gunwi-gun, Korea. The structures of these compounds were established as 3α,19α,20β,24,30-pentahydroxyurs-12-en-28-oic acid (1, glutinolic acid), aeginetic acid 5-O-β-D-quinovoside (2) and aeginetoyl ajugol 5″-O-β-D-quinovoside (3) on the basis of chemical and spectroscopic evidence.  相似文献   

12.
Arylation Reaction of Cyclic Guanidine-Analogs with α-Halo- anthraquinones: New Anthrapyrimidines 2-Amino-benzimidazole gives on Ullmann-reaction with α-halo-athraquinones such as 1-amino-4-bromoanthraquinone-2-sulfonic acid (la) the new benzimidazo-anthrapyrimidine 2a , whereas 3-amino- triazole gives under the same conditions two products: the 1,2,4-triazoloanthrapyrimidine 7 and l-amino-4-(3-amino-1,2,4- triazolyl)anthraquinone-2-sulfonic acid ( 8 ). The new structures were elucidated by 1H- and 13C-NMR. and X-ray analysis.  相似文献   

13.
九子参苷A的结构   总被引:2,自引:0,他引:2  
谭宁华  赵守训  周俊  陈昌祥 《化学学报》1995,53(10):1024-1033
从石竹科植物九子参(Silene rubicunda Franch.)根中得到一个糖链上带双乙酰基的新三萜八糖苷──九子参苷A(rubicunoside A, 1)。以化学降解反应、酶解和波谱分析, 得到15个衍生物, 其结构最后确定为皂树酸-3-O-β-D-吡喃半乳糖-(1→2)-[β-D-吡喃木糖-(1→3)]-β-D-吡喃葡萄糖醛酸-28-O-β-D-吡喃木糖-(1→3)-β-D-吡喃木糖-(1→4)-α-L-吡喃鼠李糖-(1→4)-[2'-O-乙酰基-β-D-吡喃鸡纳糖-(1→2)]-[3'-O-乙酰基]-β-D-吡喃夫糖苷{3-O-β-D-galactopyranosyl-(1→2)-[→β-D-xylopyranosyl-(1→3)]-β-D-glucuronopyranosyl quillaic acid 28-O-β-D-xylopyranosyl-(1→3)-β-D-xylopyranosyl-(1→4)-α-L-rhamnopyranosyl-(→4)-[2'-OAc-→β-D-quinovopyranosyl-(1→2)]-[3'-OAc]-β-D-fucopyranoside, 1}。同时发现甘草酸酶的两个新酶解特性。。  相似文献   

14.
Phytochemical examination of the methanol extract of the fruit bodies of the Japanese fungus Tyromyces fissilis led to the isolation of two new lanostane derivatives called tyromycic acids F (1) and G (2), together with two known compounds, tyromycic acid (3) and trametenolic acid B (4). Their structures were identified by 2D NMR, IR, and UV spectroscopy.  相似文献   

15.
A new triterpenoid saponin, together with five known saponins, were isolated from the nonpolar n-hexane fraction of the leaves of Aralia elata. The structure of the new saponin, durupcoside C, was elucidated as hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranoside on the basis of spectroscopic analysis. The known saponins were characterized as 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-beta-D-xylopyranosyl(1-->6)-beta-D-glucopyranosyl ester, hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside, oleanolic acid 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside, hederagenin 3-O-alpha-L-rhamnopyranosyl(1-->2)-alpha-L-arabinopyranoside (alpha-hederin), and hederagenin 3-O-beta-D-glucopyranosyl(1-->3)-alpha-L-arabinopyranoside (collinsonidin). In addition, two known lipids, Arisaema glyceride 3 and ceramide mixtures were also isolated and characterized. Collinsonidin and two known lipids were isolated for the first time from this plant.  相似文献   

16.
Investigation of the methanolic extract of Vietnamese inedible Xylariaceous mushroom Xylaria intracolorata resulted in the isolation of two new compounds named coloratin A [3,5-dimethoxy-2-(6-oxo-5-pentyl-6H-pyran-3-carbonyl)-benzoic acid] (1) and coloratin B (2-carbomethoxyl-3,5-dimethoxybenzoic acid) (2). Their structures were elucidated by 2D-NMR, MS, IR, and UV spectroscopy. Coloratin A (1) showed strong antimicrobial activity.  相似文献   

17.
Bioassay guided investigation of whole parts of Polygala japonica afforded two new triterpenoid saponins, characterized as 3-O-beta-D-glucopyranosyl medicagenic acid 28-O-{beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl} ester (1), 3-O-beta-D-glucopyranosyl 2-oxo-olean-12-en-23, 28-dioic acid 28-O-{beta-D-xylopyranosyl(1-->4)-[beta-D-apiofuranosyl(1-->3)]-alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl} ester (2), together with four known triterpenoid saponins (3-6). Their structures were elucidated by spectroscopic and chemical methods. Saponins 3, 4 and 5 showed significant anti-inflammation effects on carrageenan-induced acute paw edema in mouse.  相似文献   

18.
Four new plastoquinones, together with two known compounds, sargahydroquinoic acid and sargaquinoic acid, were isolated from the brown alga, Sargassum yezoense collected from the eastern coast of Korea. The structures of these compounds were elucidated based on spectroscopic analyses including NMR and MS. Their structures designated as meroterphenol A (1), B (2), C (3) and D (4) were characterized by a 6-methyl-1,4-benzohydroquinone moiety with an oxygenated diterpenoic acid chain. Meroterphenols A-D showed potent activation effects on peroxisome proliferator-activated receptor gamma (PPARγ).  相似文献   

19.
A new sucrose ester, acretoside, was isolated from the roots of the Greek endemic species Aristolochia cretica and identified as 6-O-p-coumaroyl-beta-D-fructofuranosyl-(2 --> 1)-alpha-D-glucopyranoside (1). In addition, a known sucrose ester, identified as arillatose B, two phenylpropanoid glucose esters, and five derivatives of aristolochic acid were isolated. Their structures were elucidated on the basis of MS and NMR data.  相似文献   

20.
Chemical studies on the crude methanolic extract of Coprinus micaceus, collected from the Canadian Prairie region, have resulted in the isolation of two new natural products, micaceol (1), a sterol and (Z,Z)-4-oxo-2,5-hetpadienedioic acid (2). Compound 2 was isolated for the first time as a natural product. Structures of these new compounds were established with the aid of extensive NMR spectroscopic studies. Compound 1 has shown anti-bacterial activity against Corynebacterium xerosis and Staphylococcus aureus, whereas compound 2 exhibited glutathione S-transferase inhibition.  相似文献   

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