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1.
Two new antibiotic metabolites, dacrymenone (1) and VM 3298-2 (2), were isolated from fermentations of a Dacrymyces sp., and their structures were determined by spectroscopic techniques. Dacrymenone (1) is a new eremophilane sesquiterpenoid while VM 3298-2 (2) is a bis-enol ether between methyl pyruvate and 4,6-dihydroxycyclohexan-1,3-dione. Dacrymenone (1) shows weak antibacterial and antifungal activity while VM 3298-2 (2) exhibits cytotoxic and antifungal activities.  相似文献   

2.
金铁锁根中的环肽成分   总被引:25,自引:0,他引:25  
从云南民间重要的药用植物金铁锁(Psammosilene tunicoides W.C.Wu et C.Y.Wu)的根中分离得到2个新的天然环二肽以及2个新的环八肽:金铁锁环肽A和B(psammosilenins A and B)。它们的结构经光谱方法鉴定为cyclo(-Ala-Ala-),cyclo(-Val-Ala-),cyclo(-Pro1-Phe1-Pro2-Phe2-Phe3-Ala-p  相似文献   

3.
Two known and four new quinoline and 4-quinolone type alkaloids were isolated from Ruta montana collected from Rommani (Morocco). The known compounds were 1-methyl-4-methoxy-2-quinolone and evolitrine. The structures of the new compounds were established from 1D and 2D NMR experiments including HMQC, HMBC and MS spectral methods as 2-(nonan-8-one)-(1H)-4-quinolone, 2-(nonan-8-one)-4-methoxy-quinoline, 2-(nonan-8-one)-N-methyl-4-quinolone and 2-(decan-9-one)-N-methyl-4-quinolone.  相似文献   

4.
Two new types of imidazole derivatives: N-(2-R1-5-R2-1H-imidazol-4-yl) thioureas 7a-g and N-(2-R1-5-R2-1H-imidazol-4-yl) formamides 8b,c,g were obtained in high yields by the hydrolytic degradation of 6-R1-8-R2-2-thioxo-2,3-dihydroimidazo[1,5-a]-1,3,5-triazin-4(1H)-ones 5a-g and 6-R1-8-R2-imidazo[1,5-a]-1,3,5-triazin-4(3H)-ones 6b,c,d, respectively. The tautomeric preferences of the new imidazoles were determined.  相似文献   

5.
Bioassay-guided fractionation of an EtOAc-soluble extract of the stem bark of Erythrina addisoniae (Leguminosae), using an in vitro PTP1B inhibitory assay, resulted in the isolation of three new (1-3) and three known (4-6) 2-arylbenzofuran derivatives. The new compounds were identified as 2-[2',4'-dihydroxy-3'-(3-methylbut-2-enyl)phenyl]-6-hydroxybenzofuran (1), 2-[2'-methoxy-4'-hydroxy-5'-(3-methylbut-2-enyl)phenyl]-6-hydroxybenzofuran (2), and 2-(2'-methoxy-4'-hydroxyphenyl)-5-(3-methylbut-2-enyl)-6-hydroxybenzofuran (3). The new 2-arylbenzofurans 1-3 inhibited PTP1B activity with IC(50) values ranging from 13.6+/-1.1 to 17.5+/-1.2 microM in vitro assay. On the basis of the data obtained, 2-arylbenzofurans with prenyl group may be considered as a new class of PTP1B inhibitors.  相似文献   

6.
Two new megastigmane glycosides (1 and 2) and two new flavone glycosides (3 and 4) were isolated from the methanol extract of the whole plant of Caralluma negevensis Zohary (Asclepiadaceae). The structures of the isolated compounds were characterized as (9R)-2beta,9-dihydroxymegastigma-4,7-dien-3-one-9-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (1), 2beta,9-dihydroxymegastigma-4-en-3-one 9-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (2), luteolin 3'-O-beta-D-glucopyranoside-4'-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside (3), and luteolin 3',4'-di-O-beta-D-glucopyranoside (4). The structures of the isolated compounds were established on the basis of spectral evidence and chemical transformation.  相似文献   

7.
Karyotypes of the human C32r16 line and its HPRT-mutant derivatives were compared. All three HPRT-mutant strains (TG-A, TG-E1, and TG-E2) studied were hypotetraploid and arose by genomic duplication. TG-A and TG-E had distinct karyotypes, reflecting their independent clonal origins. Both TG-E1 and TG-E2 were similar karyotypically, except that TG-E2 differed from TG-E1 by the presence of two new sets of balanced translocations and a significantly higher number of new markers, viz., 24 new markers in 14 TG-E2 cells as compared to 2 new markers in 13 TG-E1 cells. Comparison of the hypothetical 2s karyotype of C32r16 with the modal karyotypes of the mutants revealed (1) that chromosome changes occurred more frequently among marker chromosomes (57.1%) than among normal chromosomes (18.1%) and also more frequently among tetrasomic (28.6%) than among disomic (3.3%) normal chromosomes, and (2) that one member of a group of paired marker chromosomes tended to be eliminated very frequently, whereas disomic normal chromosomes retained their disomic condition. Chromosome 7 was involved in the formation of new marker chromosomes twice as much as any other chromosome, and even increased to pentasomy in TG-E1. Chromosome changes associated with 6-thioguanine treatment are briefly discussed.  相似文献   

8.
Flavonoid glycosides from Salvia moorcroftiana wall   总被引:1,自引:0,他引:1  
Phytochemical analysis of the whole plant of Salvia moorcroftiana Wall. (Lamiaceae) resulted in the isolation of two new flavonoid glycosides, together with three known compounds. The structures of the new compounds were established as genkwanin 4'-O-alpha-L-arabinopyranosyl-(1-->6)-beta-D-galactopyranoside (1) and genkwanin 4'-O-[alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl-(1-->6)]-beta-D-galactopyranoside] (2). The structures of all compounds were elucidated by spectroscopic methods, including 2D NMR techniques.  相似文献   

9.
Phytochemical analysis of the polar extracts of the leaves of Helleborus viridis (Ranunculaceae) resulted in the isolation of two new furostanol saponins (25R)-26-[(alpha-L-rhamnopyranosyl)oxy]-22alpha-methoxyfurost-5-en-3beta-yl O-beta-D-glucopyranosyl-(1-->3)-O-[6-acetyl-beta-D-glucopyranosyl-(1-->3)]-O-beta-D-glucopyranoside (1) and (25R)-26-[(alpha-L-rhamnopyranosyl)oxy]-22alpha-methoxyfurost-5-en-3beta-yl O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->3)-O-beta-D-glucopyranoside (2) and three new quercetin glycosides, quercetin 3-O-(2-E-caffeoyl)-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside-7-O-beta-d-glucopyranoside (3), quercetin 3-O-(2-E-caffeoyl)-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside (4), and quercetin 3-O-alpha-L-arabinopyranosyl-(1-->2)-beta-D-galactopyranoside (5). The structures of the new compounds were determined by spectroscopic analysis, including 2D NMR data and mass spectrometry.  相似文献   

10.
Two new phenylethanoid glycosides integrifoliosides A (2) and B (3), along with a known phenylethanoid glycoside alyssonoside (1) and a flavone glucoside chrysoeriol-7-O-beta-D-glucopyranoside (4) were isolated from the aerial parts of Phlomis integrifolia. The structures of the new compounds were identified as 3,4-dihydroxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (2) and 3-hydroxy-4-methoxy-beta-phenylethoxy-O-beta-D-apiofuranosyl-(1 --> 4)-alpha-L-rhamnopyranosyl-(1 --> 3)-4-O-feruloyl-beta-D-glucopyranoside (3), on the basis of spectroscopic (UV, IR, 1D- and 2D-NMR, and HR-FABMS) methods.  相似文献   

11.
The new PN ligands 5, 6 and 7 were prepared by Schiff base condensation of 2-formylphenyl(diphenyl)phosphine (1) with the optically active amines (R)-(−)-2-aminobutanol (2), (S)-(+)-2-aminobutanol (3) and (1S,2S)-2-amino- 1-phenyl-1,3-propanediol (4). These new ligands were used in the Pd catalysed allylation of 1,5-dimethylbarbituric acid with allylacetate. 5-Allyl-1,5-dimethylbarbituric acid was obtained with an optical induction of up to 12.7% ee.  相似文献   

12.
蝉翼藤茎中的两个新酮成分(英文)   总被引:1,自引:0,他引:1  
首次从蝉翼藤 (SecuridacainappendiculataHassk)茎乙醇提取物的乙酸乙酯部分分离到两个新的具有抗氧化作用的口山酮类化合物securixanthoneC (1)和securixanthoneD (2 )。这两个新化合物的结构是通过波谱方法 (1D_NMR和 2D_NMR、EI_MS、UV和IR)鉴定的。  相似文献   

13.
A new indole derivative colletoindole A ( 1 ), along with two new indole derivatives ( 2 and 3 ) and one known compound acropyrone ( 4 ) were isolated from cultures of Colletotrichum tropicale SCSIO 41022 derived from a mangrove plant Kandelia candel. The structures of 1 – 4 were determined by analysis of NMR and MS data. The cytotoxicity of 1 , 2 and 4 , and the COX‐2 inhibitory activity of 1 and 2 were evaluated.  相似文献   

14.
A new phosphonoglycosphingolipid containing two 2-aminoethylphosphonate residues was isolated from the skin of Aplysia kurodai, a marine gastropod, using two systems of silicic acid chromatography. By methanolysis, permethylation, mild acid hydrolysis and hydrogen fluoride treatment combined with thin layer chromatography and gas chromatography-mass spectrometry, the new phosphonoglycosphingolipid was shown to be 3-O-MeGal (1----3) GalNAc (1----3) [6'-O-(2-aminoethylphosphonyl) Gal (1----2)] [2-aminoethylphosphonyl (----6)] Gal (1----4) Glc (1----1) ceramide. Most of the fatty acid (90 per cent) was palmitic acid. Octadeca-4-sphingenine and anteiso-nonadeca-4-sphingenine were the major sphingosine bases of the new glycolipid.  相似文献   

15.
簇序草化学成分的研究   总被引:1,自引:0,他引:1  
首次从族序草(Craniotome furcata(Link.)O.Kuntze)的乙酸乙酯部分分离到化合物cranioside A(1)、cranioside B(2)、mussaenoside(3)和ningpogenin(4)。利用波谱方法(^1H-NMR,^13C-NMR和ESI-MS等)对这些化合物的结构进行了鉴定,其中1和2为新化合物。  相似文献   

16.
Six triterpene saponins, including two new compounds, were isolated from the fruits of Hedera helix L. (Araliaceae). The structures of the new compounds, named helixosides A and B, were established as 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl hederagenin 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, and 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, respectively, on the basis of chemical and spectral data.  相似文献   

17.
为植物界最大的类群—被子植物建立一个能真正反映植物的进化历史和系统发育(phylogeny)的分类系统一直是许多植物系统学家和进化学家所向往的。到目前为止,已经提出的被子植物分类系统至少有二十多个。问题在于这样的分类系统能否说已符合于系统发育的要求?要回答这个问题,首先必须弄清系统发育的真正含义是什么。  相似文献   

18.
Two new cyclobutane-type norlignans, methyl rel-(1R,2S,3S)-2-(7-methoxy-1,3-benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)cyclobutanecarboxylate (1), and methyl rel-(1R,2R,3S)-2-(7-methoxy-1,3-benzodioxol-5-yl)-3-(2,4,5-trimethoxyphenyl)cyclobutanecarboxylate (2), and a new lignanamide, 3-hydroxy-N-[2-(4-hydroxyphenyl)ethyl]-α-[4-(2-{N-[2-(4-hydroxyphenyl)ethyl]carbamoyl}ethenyl)-3-methoxyphenoxy]-4-methoxycinnamamide 4,8″-ether (3), along with five known amides, 4-8, were obtained from the whole plant of Peperomia tetraphylla. Their structures were elucidated mainly by the analysis of NMR and MS data. The new compounds 1-3 and the known compound 4 were tested for their cytotoxic activities against the HepG2 (human hepatocarcinoma), A549 (human lung cancer), and HeLa (human cervical cancer) cell lines. Compound 4 showed significant cytotoxicity against HepG2 cell lines with an IC(50) value of 9.4 ± 1.0?μM.  相似文献   

19.
Four compounds, craniosides A (1) and B (2), mussaenoside (3) and ningpogenin (4) were isolated from the ethyl acetate fraction of Craniotome furcata (Link.) O. Kuntze for the first time. Among them, craniosides A (1) and B (2) were identified as new compounds. The structures of the two new compounds were assigned mainly by spectral methods.  相似文献   

20.
Mass-directed isolation of the CH(2)Cl(2)/CH(3)OH extract from the marine bryozoan Amathia tortusa resulted in the purification of two new brominated alkaloids, convolutamines I (1) and J (2). The structures of 1 and 2 were determined following spectroscopic data analysis. Both compounds were isolated during a drug discovery program aimed at identifying new antitrypanosomal leads from a prefractionated natural product library. Compounds 1 and 2 were shown to be active toward the parasite Trypanosoma brucei brucei with IC(50) values of 1.1 and 13.7 μM, respectively. Preliminary toxicity profiling was also performed on both 1 and 2 using the human embryonic kidney cell line, HEK293. Compound 1 was shown to exhibit cytotoxicity against HEK293 with an IC(50) of 22.0 μM whilst 2 was inactive at 41.0 μM.  相似文献   

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