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1.
A New Annonaceous acetogenin,squamostolide(1),was isolated from the seeds of Annona squamosa.Its structure was elucidated based on spectroscopic methods and comparison with known compounds.It is the first example of Annonaceous acetogenin with each of the two ends of the aliphatic chain bearing a γ-lactone.Thenew compound exhibited cytotoxic activity in vitro against bel-7402 and CNE2 human tumor cell lines.  相似文献   
2.
The cyclopeptide, squamtin A (1, formula: C39H60O11N8S), was found to crystallized in two pseudopolymorphisms, i.e. 1·(H2O)3.5 and 1·(H2O)3.9. The composition of the amino acids and their linkage sequences are the same. The main differences between the two kinds of crystals lie in the positions and occupancies of the water molecules, the positions of the sulfur atoms and the conformation of the side chains. The absolute configuration of 1 is established by X-ray analysis in combination with the Marfey's analysis of its hydrolysates.  相似文献   
3.
From the hexane and MeOH extracts of Annona coriacea Mart . (Annonaceae) seeds, two novel acetogenins, coriapentocins A and B ( 1 and 2 , resp.) were isolated. The known acetogenin bullacin ( 3 ) was also isolated from the hexane extract. The structures of compounds 1 – 3 were elucidated by NMR and MS analysis, and relative configurations were established by comparison with literature data.  相似文献   
4.
We investigated the antidiarrhoeic effect of the aqueous extract of Annona crassiflora leaves (AEAC). The AEAC decreased the diarrhoeic stools and enteropooling induced by castor oil, without altering total faecal output; moreover, the distance travelled by charcoal meal in the intestine was increased. Twenty-eight compounds were identified by LC-DAD-MS in the AEAC, including flavonoids, alkaloids and proanthocyanidins. In addition, two oligomeric series of condensed tannins of up to nine flavan-3-ol units were characterised by MALDI-MS. These data suggest that the antidiarrhoeic effect of the AEAC is related to its ability to inhibit intestinal secretion and/or to increase intestinal absorption. Moreover, the prokinetic effect of AEAC, together with its inhibitory effect on enteropooling induced by castor oil, explains why this extract decreased diarrhoeic faeces without altering the total faecal output. All these effects are in agreement with the pharmacological activity reported in the literature for many of the secondary metabolites identified.  相似文献   
5.
A new N-fatty acyl tryptamine, cheritamine ( 30 ), along with thirty-two compounds including nineteen benzenoids, p-hydroxybenzadehyde ( 1 ), p-hydroxybenzoic acid ( 2 ), methylparabene ( 3 ), 3-chlorobenzoic acid ( 4 ), vanillin ( 5 ), isovanillin ( 6 ), vanillic acid ( 7 ), isovanillic acid ( 8 ), methyl vanillate ( 9 ), methyl isovanillate ( 10 ), syringaldehyde ( 11 ), syringic acid ( 12 ), 3,4,5-trimethoxybenzoic acid ( 13 ), trans-methyl p-coumarate ( 14 ), ferulic acid ( 15 ), p-dihydrocoumaric acid ( 16 ), 3-(4-hydroxy-3,5-dimethoxyphenyl)-1,2-propanediol ( 17 ), 3,4,5 -trimethoxyphenyl-β-D-glucopyranoside ( 18 ) and thalictoside ( 19 ); one p-quinone, 2,6-dimethoxy-p-quinone ( 20 ); one purine, uridine ( 21 ); eight alkaloids, nicotinic acid ( 22 ), thalifoline ( 23 ), doryphornine ( 24 ), (–)-norstephalagine ( 25 ), (-)-romucosine ( 26 ), (+)-pronuciferine ( 27 ), (+)-norisocorydine ( 28 ) and oxoasimilobine (29) and three steroids, β-sitosterol-D-glucoside ( 31 ), stigmasterol-D-glucoside ( 32 ) and 6′-(β-sitosteryl-3-O-β-glucopyranosidyl)hexadecanoate ( 33 ), are isolated from the stems of Annona cherimola. These compounds were characterized and identified by physical and spectral evidence.  相似文献   
6.
Annona muricata (Am) is a plant used in traditional Mexican medicine to treat cancer. In this study, ethanol extracts of Am collected in Acapulco and Tecpan from Guerrero state were evaluated orally on Balb/c mice inoculated with 4T1 cells, for cytotoxic activity (CA) on 4T1 cells, in brine shrimp lethality assay (BSLA), and for acute oral toxicity in mice. In addition, ethanol extracts were subjected to high-performance liquid chromatography (HPLC) with diode array detection. Results showed that the extracts collected in December in Acapulco (AcDe) and Tecpan (TeDe) exhibited the most significant antitumor and cytotoxic activity. In the BSLA, the most important effect was observed in the extracts from Acapulco and Tecpan collected in June (AcJu) and August (TeAg), respectively. The samples from Acapulco (AcJu, and AcAg) and Tecpan (TeJu and TeAg) showed the highest toxicity. The analysis of the extracts, AcDe and TeDe, by HPLC revealed that flavonoids, rutin, narcissin, and nicotinflorin were the major components. These findings suggest that extracts from Am collected in Acapulco and Tecpan in the month of December may be an important source to obtain flavonoid glycosides with anticancer potential specifically against breast cancer. This also supports the use of Am to treat cancer in Mexican traditional medicine.  相似文献   
7.
从刺果番荔枝(Annonamuricata)的种子分离得到两个新成分,此两成分及其衍生化物经光谱分析,鉴定为两个新番荔枝肉酯,命名为MuricatinA和MuricatinB。它们属无THF环番荔枝内酯。  相似文献   
8.
气相色谱-质谱测定樟林番荔枝种子挥发油的脂肪酸组成   总被引:1,自引:0,他引:1  
用溶剂萃取法提取樟林番荔枝果实种子中的挥发性物质,测定出其挥发油质量分数为13.3%;利用GC-MS方法分离确认出其中的9种化学成分;用面积归一化法得出了9种脂肪酸在挥发油中的质量分数;其中9-十八烯酸占49.42%,十六酸占20.37%,十八酸占14.16%,9,2-十八二烯酸占13.59%;不饱和脂肪酸,占63.01%.该项研究给番荔枝果实的深入开发利用及种质资源的有效保护提供了科学依据.  相似文献   
9.
Chemical investigation of the endophytic fungus Diaporthe melonis, isolated from Annona squamosa, yielded two new dihydroanthracenone atropodiastereomers, diaporthemins A (1) and B (2), together with the known flavomannin-6,6′-di-O-methyl ether (3). The structures of the new compounds were established on the basis of extensive 1D and 2D NMR spectroscopy, as well as by high resolution mass spectrometry and by CD spectroscopy. Compounds 13 were tested for their antimicrobial activity against a multi-resistant clinical isolate of Staphylococcus aureus 25697, a susceptible reference strain of S. aureus ATCC 29213 and against Streptococcus pneumoniae ATCC 49619. Compound 3 strongly inhibited S. pneumonia growth with a MIC value of 2 μg/mL, and showed moderate activity against the S. aureus multi-resistant clinical isolate and susceptible reference strain (MIC 32 μg/mL), whereas 1 and 2 were not active against the tested strains.  相似文献   
10.
A rapid, simple, sensitive, gradient and reproducible, reverse‐phase high‐performance liquid chromatographic method was developed for the quantitative estimation of bioactive alkaloids, lysergol and chanoclavine in the seeds of Ipomoea muricata. The clavine alkaloid, lysergol, is a bioenhancer for the drugs and nutrients. The samples were analyzed by reverse‐phase chromatography on a Waters spherisorb ODS2 column (250 × 4.6 mm, i.d., 10 µm) using binary gradient elution with acetonitrile and 0.01 m phosphate buffer (NaH2PO4) containing 0.1% glacial acetic acid at a flow rate of 0.8 mL/min, a column temperature of 25 °C and UV detection at λ 254 nm. The limits of detection (LOD) and quantitation (LOQ) were 0.035 and 0.106 µg/mL for lysergol and 0.039 and 0.118 µg/mL for chanoclavine, respectively. Standard curves were linear in the range of 2–10 µg/mL (r > 99) for both analytes. Good results were achieved with respect to repeatability (RSD < 2%) and recovery (99.20–102.0). The method was validated for linearity, accuracy repeatability, LOQ and LOD. The method is simple, accurate and precise, and may be recommended for routine quality control analysis of I. muricata seed extracts containing these two clavine alkaloids (1, 2) as bioactive principles of the herb. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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