Coumarins and carbazoles with antiplasmodial activity from Clausena harmandiana

Activity guided fractionation of extracts from Clausena harmandiana have led to the identification of four known compounds, heptaphylline (1), clausine K (2), dentatin (5), and clausarin (6). All these compounds, except clausine K (2), exhibited antiplasmodial activity against Plasmodium falciparum. While the new dimethylated derivative 4, derived from 2, showed no antiplasmodial activity, the monomethylated product 3 (clausine H) exhibited activity comparable to that observed for compounds 1 and 5.     

Carbazole alkaloids from the stems of Clausena excavata

A new carbazole alkaloid, sansoakamine (8), together with 11 known compounds, was isolated from the stems of Clausena excavata. All structures were elucidated by spectroscopic methods. Compound 7 showed moderate anti-malarial activity against Plasmodium falciparum with a MIC value of 6.74 μg/ml.     

Coumarins from the bark of Juglans mandshurica exhibited anti-hepatoma activities via inducing apoptosis

Hepatocellular carcinoma (HCC), the most common type of liver cancer, has high morbidity and mortality rates, and its prognosis is poor. The treatment options of HCC are limited by the lack of effective chemotherapy. Therefore, looking for effective drugs with little toxicity is very urgent. The aim of this study was to search for small molecule targeting on liver cancer from Juglans mandshurica, which has been used to treat cancers for a long time in China. Under the guide of anti-hepatoma activity, a new coumarin (1), together with eight reported analogs (2?9), was isolated from the 75% EtOH extract. The structures of these compounds were determined by 1D and 2D NMR experiments. The absolute configuration of 1 was established by comparison of experimental and calculated electronic circular dichroism (ECD) spectra. The in vitro cytotoxicity experiments on two liver cancer cell lines (HepG2 and Hep3B) showed that compounds 2 and 5 had moderate antitumor activities on both cell lines. And further studies of antitumor mechanisms by the observation of morphological changes and Western blot analyses exhibited that induction of apoptosis might be a possible way that inhibited cell growth.     

GC-MS法分析黄皮叶和假黄皮叶中挥发油成分的差异

目的:分析黄皮叶和假黄皮叶中挥发油成分的差异。方法:通过水蒸气蒸馏法分别提取黄皮叶和假黄皮叶中的挥发油。然后采用气相色谱-质谱联用(GC-MS)技术进样分析获得总离子流图,采用HPMSD化学工作站对总离子流图中各色谱峰进行质谱扫描后,通过检索比对图谱库NIST Version 1.7鉴定两种药材中挥发油的化学成分,并采用峰面积归一化法计算各成分的相对质量分数。结果:从黄皮叶、假黄皮叶挥发油中分别鉴定出了43、31个成分,相对质量分数总和分别为97.59%、98.57%。其中,相对质量分数超过1%的成分分别有19、18个,均主要为倍半萜类;相对质量分数超过5%的挥发油成分分别有7、5个,在黄皮叶挥发油中主要以(-)-斯巴醇(12.35%)和(E)-5-{(1R,3R,6S)-2,3-二甲基三环[2.2.1.02,6]庚烷-3-基}-2-甲基戊-2-烯醛(14.70%)为主,在假黄皮叶中主要以(E)-倍半水合桧烯(24.94%)和1-(1,5-二甲基-4-己烯基)-4-甲基-苯(16.15%)为主。两者中共有挥发油成分4个,分别为α-蛇麻烯、(E)-5-{(1R,3R,6S)-2,3-二甲基三环[2.2.1.02,6]庚烷-3-基}-2-甲基戊-2-烯醛、石竹烯氧化物和(-)-斯巴醇,两者中共有成分含量差异均不大。结论:黄皮叶和假黄皮叶挥发油中成分类型基本相似,但具体成分组成和含量差异较大,不可相互替代使用。     

Clausine Z, a new carbazole alkaloid from Clausena excavata with inhibitory activity on CDK5

A new carbazole alkaloid, named clausine Z, has been isolated from the stems and leaves of Clausena excavata Burm. (Rutaceae). Its structure was established by spectroscopic methods. The compound exhibits inhibitory activity against cyclin-dependent kinase 5 (CDK5) and shows protective effects on cerebellar granule neurons in vitro.     

Coumarins from Daphne feddei and their potential anti-inflammatory activities

Chemical examination of the methanolic extract from the stem bark of Daphne feddei led to the isolation of three new dicoumarin glucosides (1–3), and eight known coumarins, dicoumarins and dicoumarin glucosides. Their structures were elucidated by extensive analysis of spectral data and comparison with the literature values. All compounds were tested for inhibitory activity against lipopolysaccharide-induced NO production in RAW 264.7 macrophages, and compounds 4 and 5 showed potent inhibitory activity with IC₅₀ values of 0.161 and 0.127 μM, respectively.     

Coumarins from Daphne feddei and their potential anti-inflammatory activities

Chemical examination of the methanolic extract from the stem bark of Daphne feddei led to the isolation of three new dicoumarin glucosides (1-3), and eight known coumarins, dicoumarins and dicoumarin glucosides. Their structures were elucidated by extensive analysis of spectral data and comparison with the literature values. All compounds were tested for inhibitory activity against lipopolysaccharide-induced NO production in RAW 264.7 macrophages, and compounds 4 and 5 showed potent inhibitory activity with IC?? values of 0.161 and 0.127 μM, respectively.     

Clauraila E from the roots of Clausena harmandiana and antifungal activity against Pythium insidiosum

A new carbazole alkaloid named clauraila E (1) together with 8 known compounds were isolated from the methanol extract of the roots of Clausena harmandiana. All compounds were evaluated for antifungal activity against Pythium insidiosum using disc diffusion assay. Pythium insidiosum is a fungus-like microorganism, for which antifungals available now are not effective. It was found that compounds 3, 6, 7 and 9 could inhibit the mycelia growth of P. insidiosum. The results show convincingly that they may be lead to compounds for the development of probiotic or novel antifungal drugs.     

Synthesis, antimycobacterial and antifungal evaluation of 3-arylaminopyrazine-2,5-dicarbonitriles

This paper describes preparation and biological evaluation of pyrazinamide analogues. Pyrazinamide with its simple structure gives a good opportunity for further modification regarding an increase of its antimycobacterial activity. We prepared a series of compounds derived from pyrazine-2,5-dicarbonitrile with arylamino substitution in position 3. All compounds were assayed in vitro against major Mycobacterium and various Fungi species. The best activity was found in 3-{[3-(trifluoromethyl)phenyl]amino}pyrazine-2,5-dicarbonitrile 11 with the value of 6.25 micromol(-1) against M. tuberculosis H(37)Rv and moderate activity against minor Mycobacterium pathogens.     

Antibacterial,antifungal, and antimycobacterial activity of Ilex aquifolium leaves

The objective of this study was to examine antibacterial, antifungal, and antimycobacterial properties of Ilex aquifolium L. (Aquifoliaceae) growing in Turkey. The ethanol, ethyl acetate, chloroform, and n-hexane extracts prepared from the leaves of I. aquifolium were tested against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter aerogenes, Proteus vulgaris, Salmonella typhimurium, and Candida albicans for antibacterial and antifungal evaluation using the microdilution broth susceptibility assay. In addition, antimycobacterial activity of the crude extracts of I. aquifolium was evaluated by microplate Alamar blue assay. The results showed that the extracts tested, except n-hexane, possessed moderate antibacterial and antifungal activity varying from 62.5 to 250?μg/mL. On the other hand, the ethanol extract of the leaves exhibited a minimum inhibitory concentration value (MIC) against Mycobacterium tuberculosis H₃₇Ra strain of 200 μg/mL.     

Antibacterial, antifungal and cytotoxic activities of amblyone isolated from Amorphophallus campanulatus

Objective:

To assess the in vitro antibacterial, antifungal and cytotoxic activities of amblyone, a triterpenoid isolated from Amorphophallus campanulatus (Roxb).

Methods:

Disc diffusion technique was used for in vitro antibacterial and antifungal screening. Cytotoxicity was determined against brine shrimp nauplii. In addition, minimum inhibitory concentration (MIC) was determined using serial dilution technique to determine the antibacterial potency.

Results:

Large zones of inhibition were observed in disc diffusion antibacterial screening against four Gram-positive bacteria (Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus and Streptococcus pyogenes) and six Gram-negative bacteria (Escherichia coli, Shigella dysenteriae, Shigella sonnei, Shigella flexneri, Pseudomonas aeruginosa and Salmonella typhi). The MIC values against these bacteria ranged from 8 to 64 μg/ml. In antifungal screening, the compound showed small zones of inhibition against Aspergillus flavus, Aspergillus niger and Rhizopus aryzae. Candida albicans was resistant against the compound. In the cytotoxicity determination, LC₅₀ of the compound against brine shrimp nauplii was 13.25 μg/ml.

Conclusions:

These results suggest that the compound has good antibacterial activity against the tested bacteria, moderate cytotoxicity against brine shrimp nauplii and insignificant antifungal activity against the tested fungi.     

Antibacterial,antifungal and cytotoxic activities of salviasperanol isolated from Amorphophallus campanulatus

Salviasperanol, a diterpenoid isolated from Amorphophallus campanulatus (Roxb.) Bl. (Araceae) was studied for in vitro antibacterial, antifungal, and cytotoxic activities. The disc diffusion technique was used to determine in vitro antibacterial and antifungal activities. Cytotoxicity was determined against brine shrimp nauplii. In addition, minimal inhibitory concentration (MIC) was determined using serial dilution technique to determine antibacterial potency. The MIC values against these bacteria ranged from 8 to 64 μg/mL. The compound showed significant antibacterial activity against four Gram-positive bacteria (Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Streptococcus β-haemolyticus) and six Gram-negative bacteria (Escherichia coli, Shigella dysenteriae, Shigella sonnei, Shigella flexneri, Pseudomonus aeruginosa, Salmonella typhi). The compound showed weak antifungal activity against a number of fungi. In the cytotoxicity determination, the LC₅₀ of the compound against brine shrimp nauplii was 8.02 μg/mL.     

Synthesis and antifungal activities of N-arylideneaminoimidazole derivatives

The synthesis and microbiological activities of 1-arylideneaminoimidazole derivatives are reported. Antimicrobial data show that some of the tested imidazoles exhibited an interesting activity on Candida albicans.     

Evaluation of antifungal and DNA-damaging activities of alkaloids from branches of Porcelia macrocarpa

Bioactivity-guided fractionation of the alkaloidal fractions of the CH2Cl2 extract from branches of Porcelia macrocarpa using mutant yeast strains of Saccharomyces cerevisiae and fungi Cladosporium cladosporioides and C. sphaerospermum led to the isolation of bioactive alkaloids: two tetrahydrobenzylisoquinolines (1 and 2), two aporphines (3 and 4), one proaporphine (5), one oxoaporphine (6), four azantraquinones (7-10) and four azafluorenones (11-14). The alkaloids cleistopholine (7) and 6-methoxycleistopholine (8) showed the highest fungitoxic activity while the mixture of 6- and 7-methoxyonychine (12+13) and 6,7-dimethoxyonychine (14) showed a weak DNA-damaging potential.     

Bioenhancing and antimycobacterial agents from Ammannia multiflora

The methanolic extract of Ammannia multiflora (Lythraceae) showed significant bioenhancing activity with the antibiotic nalidixic acid. Bioassay-guided fractionation of MeOH extract resulted in the isolation of a novel compound, 2,5-bis-(3,3'-hydroxyaryl)tetrahydrofuran, named as ammaniol (5), along with 9 other known compounds (1-4, 6-10). Furthermore, compound 4-hydroxy- α-tetralone (1) was converted into five semisynthetic acyl derivatives, 1A-1E, which were evaluated along with compounds 1, 5, 6, 9, and 10 for their bioenhancing activity in combination with nalidixic acid against the two strains, CA8000 and DH5 α, of Escherichia coli. The results showed that the methanolic extract of A. multiflora and compounds 1 and 9 possessed significant bioenhancing activity and reduced the dose of nalidixic acid fourfold while compounds 5, 6, 10 and semisynthetic derivatives 1A- 1E reduced the dose of nalidixic acid twofold. Compound 5 was also tested for antimycobacterial activity against Mycobacterium H37Rv and was found to show moderate activity (MIC 25?μg/mL) against this pathogen.     

黄皮种子中香豆素类化合物的分离、鉴定及其α-葡萄糖苷酶抑制活性和全齿复活线虫致死活性研究

目的:分离、鉴定黄皮种子中香豆素类化合物,并研究其α-葡萄糖苷酶抑制活性和全齿复活线虫致死活性。方法:采用柱层析、反相硅胶柱色谱及高效液相色谱技术对黄皮种子的香豆素类化合物进行分离、纯化,并根据理化性质和氢谱(1H-NMR)、碳谱(13C-NMR)数据进行结构鉴定。分别以阿卡波糖、阿维菌素为阳性对照,采用对硝基苯基-α-D-吡喃葡萄糖苷(PNPG)法和贝曼漏斗法分别对上述化合物进行体外α-葡萄糖苷酶抑制活性和全齿复活线虫致死活性考察。结果:从黄皮种子中共分离鉴定出7个香豆素类化合物,分别为7-羟基香豆素(Ⅰ)、黄皮呋喃香豆精(Ⅱ)、Lansiumarin-C(Ⅲ)、Claucoumarin A(Ⅳ)、ClausenalansiminA(Ⅴ)、(E,E)-8-(7-羟基-3,7-二甲基-2,5-二烯基)补骨脂(Ⅵ)、Dihydroindicolactone(Ⅶ)。在质量浓度为0.25 mg/mL时,化合物Ⅰ、Ⅲ、Ⅴ的α-葡萄糖苷酶抑制率分别为(32.4±1.9)%、(37.1±6.0)%、(39.5±1.1)%;在质量浓度为2.5 mg/mL时,化合物Ⅰ、Ⅳ的线虫校正死亡率分别为50.5%、47.9%。结论:香豆素类化合物Ⅰ、Ⅲ、Ⅴ具有α-葡萄糖苷酶抑制活性,化合物Ⅰ、Ⅳ具有全齿复活线虫致死活性。其中,化合物Ⅲ、Ⅴ的α-葡萄糖苷酶抑制活性、化合物Ⅳ的全齿复活线虫致死活性均为首次发现。     

Antibacterial and antifungal activities of some trimethoprim salts

In this study, the antimicrobial activities of Trimethoprim (1), Trimethoprim + Maleic acid (2), Trimethoprim + Oxalic acid dihydrate (3), and Trimethoprim + trans-1,2-Cyclohexanedicarboxylic acid (4) were investigated for their in vitro growth inhibitory activity against human pathogenic as some bacteria and fungi. Substances were tested using the micro-broth dilution assay. The chemical agents showed the same activity against Escherichia coli, Pseudomonas aeruginosa, and Proteus vulgaris. Inhibitory activities of test chemicals against different Candida strains were determined to be widely moderate.     

新型三唑类衍生物的合成及其抗真菌活性研究

目的：研究具有萘苄结构的三唑醇类化合物的抗真菌活性。方法设计合成了9个目标化合物;其结构通过1 H NMR、MS确证,选择8种真菌为实验菌株,根据美国国家临床实验室标准委员会（NCCLS）推荐的标准化抗真菌敏感性实验方法,进行体外抑菌活性测试。结果所有化合物对所选真菌均表现出了一定的抑菌活性,化合物1c对除烟曲霉菌以外的其他7种真菌的MIC80值＜0．125μg/ml,是伏立康唑活性的16倍。结论引入萘环和烃基侧链的目标化合物都有抗真菌活性。