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1.
Lowdenic acid (1), a new antifungal metabolite with an unusual structure and a mixed biogenetic origin, has been obtained from nonsporulating cultures of a previously undescribed Verticillium sp. (MYC-406 = NRRL 29280) that was isolated as a colonist of polypore basidiomata. The gross structure of 1 was proposed by analysis of NMR data and confirmed by X-ray diffraction analysis, which enabled assignment of relative stereochemistry. Compound 1 occurs as an equilibrium E/Z mixture. The known antifungal metabolite canescin A (2) was also isolated.  相似文献   

2.
Fatty acid synthase (FAS) has been identified as a potential antifungal target. FAS prepared from Saccharomyces cerevisiae was employed for bioactivity-guided fractionation of Chlorophora tinctoria,Paspalum conjugatum, Symphonia globulifera, Buchenavia parviflora, and Miconia pilgeriana. Thirteen compounds (1-13), including three new natural products (1, 4, 12), were isolated and their structures identified by spectroscopic interpretation. They represented five chemotypes, namely, isoflavones, flavones, biflavonoids, hydrolyzable tannin-related derivatives, and triterpenoids. 3'-Formylgenistein (1) and ellagic acid 4-O-alpha-l-rhamnopyranoside (9) were the most potent compounds against FAS, with IC(50) values of 2.3 and 7.5 microg/mL, respectively. Furthermore, 43 (14-56) analogues of the five chemotypes from our natural product repository and commercial sources were tested for their FAS inhibitory activity. Structure-activity relationships for some chemotypes were investigated. All these compounds were further evaluated for antifungal activity against Candida albicans and Cryptococcus neoformans. Although there were several antifungal compounds in the set, correlation between the FAS inhibitory activity and antifungal activity could not be defined.  相似文献   

3.
Piper crassinervium, P. aduncum, P. hostmannianum, and P. gaudichaudianum contain the new benzoic acid derivatives crassinervic acid (1), aduncumene (8), hostmaniane (18), and gaudichaudianic acid (20), respectively, as major secondary metabolites. Additionally, 19 known compounds such as benzoic acids, chromenes, and flavonoids were isolated and identified. The antifungal activity of these compounds was evaluated by bioautographic TLC assay against Cladosporium cladosporioides and C. sphaerospermum.  相似文献   

4.
Five new asterric acid derivatives, ethyl asterrate (3), n-butyl asterrate (4), and geomycins A-C (6-8), have been isolated from cultures of an isolate of the Antarctic ascomycete fungus Geomyces sp. The structures of these metabolites were elucidated by NMR spectroscopy. The absolute configuration of 8 was determined by application of the CD excitation chirality method. Compound 7 displayed antifungal activity against Aspergillus fumigatus, whereas 8 showed antimicrobial activities against gram-positive and gram-negative bacteria.  相似文献   

5.
 目的设计合成2,3,3a,4-四氢硫色烯并[4,3-c]吡唑类化合物,并对其抗真菌活性进行初步评价。方法以取代苯硫酚为起始原料,首先合成中间体3-次苄基硫色满酮;然后利用水合肼和3-次苄基硫色满酮在醋酸中反应生成目标化合物。采用二倍稀释法对目标化合物的体外抗真菌活性进行测试。结果共合成了8个新的2,3,3a,4-四氢硫色烯并[4,3-c]吡唑类化合物,并经过H-核磁共振、质谱和元素分析等确认了其结构。抗真菌活性实验结果表明,目标化合物对大部分供试真菌具有好的活性。结论2,3,3a,4-四氢硫色烯并[4,3-c]吡唑类化合物在体外具有抗真菌活性,有待深入研究。  相似文献   

6.
Hassallidin A (1), a new antifungal glycosylated lipopeptide, was isolated from an epilithic cyanobacterium collected in Bellano, Italy, identified as Tolypothrix (basionym Hassallia) species. Chemical, mass spectrometric, and spectroscopic analyses, including one- and two-dimensional NMR, were performed to determine an esterified eight-residue cyclic peptide linked with a carbohydrate and a fatty acid residue. Chiral GC-MS analysis revealed the occurrence of the nonproteinogenic amino acids D-allo-Thr, D-Thr, D-Tyr, D-Gln, and dehydroaminobutyric acid (Dhb) within the peptide moiety. The additional components of hassallidin A could be identified as alpha,beta-dihydroxytetradecanoic acid (Dht) and mannose. This is the first report on a cyclic peptide of cyanobacterial origin that contains both a fatty acid and a carbohydrate moiety. Compound 1 exhibits antifungal activity against Aspergillus fumigatus and Candida albicans with MIC values of 4.8 microg/mL for both test organisms.  相似文献   

7.
A systematic screen for new natural products that displayed antifungal activity by inhibition of fungal fatty acid synthase (FAS) led to the discovery of two new fungal metabolites, designated CT2108A (1) and CT2108B (2). The metabolites were produced by Penicillium solitum (Westling) strain CT2108 and were classified as azaphilones. The structures of these new metabolites were determined using a variety of 1D and 2D NMR experiments, including COSY, HMQC, and HMBC. The chemical conversion of CT2108A to CT2108B was effected using WCl(6). The related metabolite, patulodin (3), was also isolated from the fermentation culture of this P. solitum isolate. Both new compounds inhibited fungal FAS, and neither was found to significantly inhibit human FAS activity.  相似文献   

8.
土荆皮抗真菌化学成分研究   总被引:3,自引:1,他引:2  
徐云辉  张帅  张念  孔德云  华茉莉 《中草药》2012,43(2):220-222
目的对土荆皮Pseudolaricis Cortex抗真菌活性部位进行化学成分研究。方法土荆皮粗粉以95%乙醇回流提取,所得浸膏采用溶剂法分为不同提取部位,体外抗真菌活性测试显示其醋酸乙酯部位对白色念珠菌具有显著的抑制作用。采用硅胶、Sephadex LH-20、制备高效液相色谱对土荆皮醋酸乙酯部位进行分离纯化,并通过波谱数据分析对化合物进行结构鉴定。结果从土荆皮醋酸乙酯部位分离得到5个化合物,分别鉴定为土荆皮酸B(1)、土荆皮酸C(2)、香草酸(3)、香草酸-4-O-β-D-阿洛糖苷(4)、17-羟基土荆皮酸B(5)。结论化合物5为一新化合物,命名为土荆皮酸I;化合物4为首次从该植物中分离得到。体外抗真菌活性测试显示,化合物1对白色念珠菌生长具有显著的抑制作用,化合物2和5仅显示微弱的抑菌活性。  相似文献   

9.
The natural product dihydroferulic acid (DFA, 1) and the synthesized DFA methyl (4a), ethyl (4b), propyl (4c), hexyl (4d), octyl (4e), and decyl (4f) esters were examined for antifungal activity. Test fungi included Saccharomyces cerevisiae (wild type, and deletion mutants slt2 Delta and bck1 Delta), Aspergillus fumigatus, and A. flavus. Growth inhibition of S. cerevisiae treated with 5 mM DFA or the corresponding esters was 4a, 4b, and 4c >98%; 4d 18.8%; 1 6.4%; 4e 6.2%; and 4f 2.8%, relative to the control. The 50% minimum inhibitory concentrations for the more active propyl, methyl, and ethyl esters were 1.5, 2.1, and 4.0 mM, respectively. Compound 4c inhibited 100% growth of both aspergilli at 6.4 mM.  相似文献   

10.
Jomthonic acid A (1), a new modified amino acid, was isolated from the culture broth of a soil-derived actinomycete of the genus Streptomyces. The structure and absolute configuration of 1 were determined by spectroscopic analyses and chemical conversion. Jomthonic acid A (1) induced differentiation of preadipocytes into mature adipocytes at 2-50 μM.  相似文献   

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