Zopfiellasins A–D,Two Pairs of Epimeric Cytochalasins from Kiwi-Associated Fungus Zopfiella sp. and Their Antibacterial Assessment

In our continuous search for antibacterial agents against Pseudomonas syringae pv. actinidiae (Psa) from kiwi-associated fungi, two pairs of epimeric cytochalasins, zopfiellasins A–D (1–4), were characterized from the fungus Zopfiella sp. The structures were established on the basis of spectroscopic data analysis, while the absolute configurations were determined by single-crystal X-ray diffraction. Compounds 1 and 3 exhibited antibacterial activity against Psa with MIC values of 25 and 50 μg/mL, respectively. This is the first report of anti-Psa activity of cytochalasin derivatives.     

Chlovalicin B,a Chlorinated Sesquiterpene Isolated from the Marine Mushroom Digitatispora marina

As part of our search for bioactive metabolites from understudied marine microorganisms, the new chlorinated metabolite chlovalicin B (1) was isolated from liquid cultures of the marine basidiomycete Digitatispora marina, which was collected and isolated from driftwood found at Vannøya, Norway. The structure of the novel compound was elucidated by spectroscopic methods including 1D and 2D NMR and analysis of HRMS data, revealing that 1 shares its molecular scaffold with a previously isolated compound, chlovalicin. This represents the first compound isolated from the Digitatispora genus, and the first reported fumagillin/ovalicin-like compound isolated from Basidiomycota. Compound 1 was evaluated for antibacterial activities against a panel of five bacteria, its ability to inhibit bacterial biofilm formation, for antifungal activity against Candida albicans, and for cytotoxic activities against malignant and non-malignant human cell lines. Compound 1 displayed weak cytotoxic activity against the human melanoma cell line A2058 (~50% survival at 50 µM). No activity was detected against biofilm formation or C. albicans at 50 µM, or against bacterial growth at 100 µM nor against the production of cytokines by the human acute monocytic leukemia cell line THP-1 at 50 µM.     

A new isochroman from the marine endophytic fungus 1893#

A new isochroman, 6-hydroxy-3-methylisochroman-5-carboxylic acid, and six known compounds were isolated from the culture of marine-derived mangrove fungus 1893#. Their structures were elucidated by analysis of spectroscopic data. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 114–116, March–April, 2006.     

双波长分光光度法同时测定水杨醛和苯酚

利用水杨醛、苯酚的紫外吸收光谱特征及水杨醛在271 nm波长处有一个等吸收点,提出了同时测定水杨醛和苯酚的双波长分光光度法。选择328 nm和271 nm为测定波长,以其回归方程为基础建立了联立方程组,C水杨醛=31.31A328 nm+0.344;C苯酚=44.53A271 nm-1.866A328 nm-0.136,求得组分浓度与吸光度之间的关系,浓度在0.005~0.030 g.L-1范围内符合朗伯-比耳定律。     

铝-水杨醛苯甲酰腙荧光反应的研究及应用

本文研究了Al~(3+)-水杨醛苯甲酰腙高灵敏度荧光体系,络合物的荧光激发波长=375nm,发射波长=450nm。铝量在0～1.4μg/10ml范围内,荧光强度与其含量成正比,灵敏度为0.4ppb。方法可用于试剂中微量铝的检测,结果令人满意。     

A new isoprenyl phenyl ether compound from mangrove fungus

A new isoprenyl phenyl ether, 3-hydroxy-4-(3-methylbut-2-enyloxy)benzoic acid methyl ester (1), together with 4-hydroxybenzoic acid (2), 2-hydroxy-6-methylbenzoic acid (3), and 4-hydroxy-3-methoxybenzoic acid (4) were isolated from Mangrove fungus (No. B60) from the South China Sea. The structures of the compounds were established on the basis of NMR spectroscopic and mass spectrometric data. In the preliminary bioassay, compound 1 exhibited antibacterial and antifungal activities. Compound 1 also inhibited cytotoxicity to the hepG2 cell line with an IC₅₀ value of 10.0 μg/mL. Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 313–314, July–August, 2007.     

Structure elucidation of three diphenyl ether derivatives from the mangrove endophytic fungus SBE‐14 from the South China Sea

Two new natural products, tenelate A ( 1 ) and B ( 2 ), together with the known compound, tenellic acid C ( 3 ), were isolated from the mangrove endophytic fungus Talaromyces sp. (SBE‐14), from the South China Sea. Their structures were elucidated by spectroscopic methods, mainly 1D and 2D NMR techniques. Copyright © 2009 John Wiley & Sons, Ltd.     

A new biphenyl derivative from an unidentified marine fungus E33

A new biphenyl derivative 3,5′-dihydroxy-4′,5-dimethoxy-2′-methyl-[1,1′-biphenyl]-2-carboxylic acid methyl ester (1), was isolated from the culture broth of a fungus isolated from the rhizosphere soil of mangrove root on the South China Sea. The structure of 1 was determined by comprehensive spectroscopic methods, primarily 2D NMR techniques. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 128–129, March–April, 2008.     

Xyloketal H from the mangrove endophytic fungus Xylaria sp. 2508

(3R*,3aR*,9aR*)-3,9a-Dimethyl-2,3,3a,9a-tetrahydro-4H-furo[2,3-b]chromene-5,7-diol (xyloketal H), a representative of a new family of xyloketals, was isolated from the marine-derived mangrove fungus Xylaria sp. 2508. Its structure was elucidated by spectroscopic data and single-crystal X-ray diffraction analysis. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1051–1052, June, 2006.     

Metabolites of the marine fungus <Emphasis Type="Italic">Humicola fuscoatra</Emphasis> KMM 4629

A new sesquiterpene of the caryophyllene series, fuscoatrol A (1), and known compounds, 11-epiterpestacin (2) and -nitropropionic acid (3), were isolated from the marine fungus Humicola fuscoatra (Traaen) KMM 4629 associated with the Kuril colonial ascidium. The structure of 1 was established on the basis of X-ray diffraction data and 2D NMR spectroscopy. The antimicrobial and cytotoxic activities of compounds 1–3 were studied.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2534–2537, November, 2004.     

水杨醛苯腙与铜荧光反应的研究及其应用

水杨醛苯腙与铜荧光反应的研究及其应用江崇球，唐波，傅红燕，曹红，张晓刚（山东师范大学化学系，济南，２５００１４）关键词铜，水杨醛苯腙，荧光分析胺类试剂是一类理想的荧光分析试剂［１］，用其测定Ａｌ３＋［２］、Ｇａ３＋［３］、Ｚｎ２＋［４］已显示出其灵敏...     

三种水杨醛类席夫碱的合成与性质研究

以取代水杨醛和3-氨基噻吩为原料合成了三种水杨醛类席夫碱,探讨了水杨醛结构中酚羟基对位取代基结构变化对于该席夫碱探针的激发态内质子转移过程、pH响应和金属离子响应的影响。研究结果表明,改变取代基团的推、吸电子能力,可调节酚氧负离子对活泼氢的束缚能力,进而影响这些席夫碱分子的激发态内质子转移性能。同时,酚氧负离子的电荷密度也决定了其与阳离子的配位能力,从而表现出不同结构的席夫碱对金属离子的选择性和灵敏性差异。     

Benzophenone and chromone derivatives and their dimers from the scale-insect pathogenic fungus Orbiocrella petchii BCC 51377

A benzophenone derivative, orbiophenone A, and its homodimer, orbiocrellone A, a chromone derivative, orbiochromone A, four benzophenone–chromone heterodimers, orbiocrellones B–E, and a benzophenone–tetrahydroxanthone dimer, ent-secalonic acid I, were isolated from cultures of the scale-insect pathogenic fungus Orbiocrella petchii BCC 51377. Their structures were elucidated by spectroscopic analyses and chemical correlations. Orbiochromone A was isolated for the first time as an optically active natural product, and its absolute configuration was determined by the ECD spectrum combined with TD-DFT calculations. Four of the dimeric compounds, orbiocrellones B–D and ent-secalonic acid I, exhibited antimalarial activity against Plasmodium falciparum K1 with IC₅₀ values of 5.7, 5.6, 14, and 5.5 μM, respectively.     

水杨醛苯甲酰腙高灵敏度荧光法测定土壤和水中痕量铍的研究

详细研究了铍－水杨醛苯甲酰腙（ＳＡＢＨ）荧光反应新体系的最佳条件在ｐＨ为６２介质中，试剂与铍所形成配合物的λｅｘ为３６５ｎｍ，λｅｍ为４４８ｎｍ，建立的铍荧光分析法的线性范围为０～０２０ｍｇ／Ｌ，检出下限５３×１０－４ｍｇ／Ｌ，相对标准偏差１４％，考察了４０种共存物的干扰情况。该法成功地用于土壤、污水和饮用水中痕量铍的测定。     

A new benzopyrans derivatives from a mangrove-derived fungus Penicillium citrinum from the South China Sea

One new benzopyran derivative (2R^*,4R^*)-3,4-dihydro-5-methoxy-2-methyl-2H-1-benzopyran-4-ol (1), together with five known compounds (2?6), were obtained from the EtOAc extract of the endophytic fungus Penicillium citrinum HL-5126 isolated from the mangrove Brguiera sexangula var. rhynchopetala collected in the South China Sea. Their structures were elucidated by the detailed analysis of comprehensive spectroscopic data. All compounds were evaluated for their antibacterial activities. Compound 6 exhibited potent inhibitory activity against Bacillus subtilis, Bacillus cereus and Micrococcus tetragenus with the same MIC values of 6.94 μM.     

Studies on the Scavenger Activities of Salicylaldehyde and Methyl Salicylate Against Hydroxyl Radical

Introduction Active oxygen species have a carcinogenesis effect, and can cause mutation, cardiovascular diseases, inflammation and aging, etc. Hydroxyl radicals generated either from a radiolysis of water contained in biological tissues or from a redox cycling implicated in a wide range chemical toxicants, have been recognized as the extremely reactive oxidative species which can attack DNA bases and sugar moiety of nucleotides and lead to radiation or chemical injury of DNA and other biological targets[1-5].Therefore, In recent years many pharmacologists and biologists are looking for effective free radical scavengers, especially naturally occurring antioxidants of oxidizing free radicals as drugs.     

Isolation and structure determination of a new indene derivative from endophytic fungus Aspergillus flavipes Y-62

As part of the search for naturally derived secondary metabolites, a novel indene derivative, compound 1, together with nine known metabolites (2–10) have been purified from an ethyl acetate extract of the plant-associated fungus Aspergillus flavipes Y-62, isolated from Suaeda glauca (Bunge) Bunge which was collected along Zhoushan coast, Zhejiang province, East China. The structure of the new compound 1 was elucidated by extensive use of spectroscopic techniques like 1D, 2D NMR, and HR-TOF-MS, while the known metabolites were established based on both spectral methods as well as by comparison with the previous literature. Compound 1 exhibited antimicrobial activities against the gram-negative pathogen Pseudomonas aeruginosa and Klebsiella pneumoniae with equal MIC values of 32 µg/ml.     

Structure elucidation and NMR assignments for three anthraquinone derivatives from the marine fungus Fusarium sp. (No. ZH‐210)

The structure elucidations and complete ¹H and ¹³C NMR assignments are reported for three new anthraquinone derivatives: Fusaquinon A (1), B (2), and C (3) isolated from the fermentation medium of the marine fungus Fusarium sp. (No. ZH‐210). HREIMS, Fourier transform infrared absorption spectrometry (FT‐IR), NMR experiments including gCOSY, gHMQC, gHMBC, and NOESY were used for the determination of the structures and NMR spectral assignments. Preliminary pharmacological test showed that they exhibited low cytotoxic activity towards KB, KBv200, and MCF‐7 cell lines. Copyright © 2009 John Wiley & Sons, Ltd.     

Penicillilactone A,a novel antibacterial 7-membered lactone derivative from the sponge-associated fungus Penicillium sp. LS54

One novel 7-membered lactone derivative, penicillilactone A (1), together with two known compounds, rugulosin A (2) and rugulosin (3) were isolated from the sponge-derived fungus Penicillium sp. LS54. Their structures were elucidated on the basis of spectroscopic analysis and comparison with literature data. Remarkably, penicillilactone A (1) is the first natural product containing a 7-membered lactone ring fused with a furan core. Penicillilactone A (1) exhibited moderate antibacterial activity against aquatic pathogen Vibrio harveyi with an MIC value of 8 μg/mL.     

A novel cyclic dipeptide from deep marine-derived fungus Aspergillus sp. SCSIOW2

A novel cyclic dipeptide, 14-hydroxy-cyclopeptine (1), was purified from a deep sea derived fungal isolate identified as an Aspergillus sp. The structure was elucidated by detailed spectroscopic analyses using 1D and 2D NMR experiments and high resolution mass spectrometry. The absolute configuration of the amino acid was determined by Marfey's method. Two conformational isomers of 1 were established by ROE analyses. 1 inhibited nitric oxide production with IC₅₀ values at 40.3 μg/mL in a lipopolysaccharide and recombinant mouse interferon-γ -activated macrophage-like cell line, RAW 264.7 and showed no cytotoxic effect in the tested dose range up to 100 μg/mL.