试剂加入次序不同造成镉对肝脂质过氧化的诱导或拮抗作用

采用TBA检测方法，体外观察了CaCl2对大鼠线粒体脂质过氧化产物丙二醛(MDA)生成的毒性作用和对半胱氨酸-Fe^2 诱导的线粒体脂质过氧化的影响。结果表明，1 μmol／L～1mol／L CdCl2均能诱导肝线粒体的脂质过氧化，使MDA含量增加，但只有CdCl2浓度高于1 mmol／L时，诱导作用才与对照组有显著性差异。在Fe^2 -Cd^2 半胱氨酸共同对肝线粒体作用时，由于试剂加入顺序的不同，100～1000 mmol／L CdCl2对线粒体脂质过氧化可产生诱导或拮抗作用。结果提示，CdCl2可直接诱导线粒体脂质过氧化，在做几种金属离子体外协同对肝脂质过氧化影响的实验时，应考虑试剂加入顺序所产生的不同影响。     

Antioxidant flavonol glycosides from Dorycnium hirsutum

Seven flavonol glycosides were isolated and identified from the aerial parts of Dorycnium hirsutum, together with catechin, D-pinitol, β-sitosterol, and stearic acid. The extracts and the isolated flavonol glycosides were evaluated for their antioxidant activity, using the DPPH test (radical scavenging) and the lipoxygenase assay (lipid peroxidation). Dedicated to the memory of Prof. I. Morelli. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 233–235, May–June, 2006.     

Aluminium(III) as a promoter of cellular oxidation

Aluminium has been known as a neurotoxic agent to experimental animals since the last century (Arch. Exp. Pharmacol. 40 (1897) 98). However, great interest arose in it bioinorganic chemistry as well biology when it was demonstrated to be the causative agent in pathologies related to the long-term dialysis treatment of uremic subjects with renal failure (Life Chem. 11 (1994) 197), and as a potential etiopathogenic cofactor for several neurodegenerative diseases. The inorganic biochemistry of aluminium is still largely to be discovered. In this review the pro-oxidative property of aluminium toward biological membrane will be presented and its implications in involvement in human pathology will be discussed in an interdisciplinary frame from the bioinorganic point of view.     

苯并异硒唑酮氨基酸衍生物的合成及抗脂质过氧化作用

在已知具有氧化作用的2-苯基-1,2-苯并异硒唑-3(2H)-酮(Ebselen)的基础上, 将其2-位苯环更换成氨基酸乙酯, 设计并合成了9个苯并异硒酮的氨基酸衍生物3～11. 这类化合物的抗氧化作用药理研究表明,它们对Fe^2^+/半胱氨酸及维生素C诱发的大鼠肝微粒体脂质过氧化有抑制活性, 部分化合物活性比母体化合物Ebselen更优.     

稀土离子对大鼠肝细胞核脂质过氧化的影响

用光度法测定丙二醛 (MDA)研究不同浓度La3 +,Ce3 +,Pr3 +,Nd3 +,Eu3 +对大鼠肝细胞核脂质过氧化的影响。结果表明 :稀土离子在 1×10 - 4 ～ 1× 10 - 6mol·L- 1 浓度范围内能抑制振荡温育或H2 O2 引起的脂质过氧化 ,且与浓度正相关。但是对大鼠肝细胞核用稀土离子处理一定时间 ,稀土离子Eu3 +对脂质过氧化的抑制作用明显减弱 ,甚至会导致脂质过氧化加强     

Allylic Peroxidations with Bis(2‐pyridylimino)isoindolato‐Cobalt and ‐Iron Complexes

Several novel substituted bis(2‐pyridylimino)isoindolato (BPI) cobalt(II) and iron(II) complexes [M(BPI)(OAc)(H₂O)] (M = Co: 1 ‐ 6, Fe: 7) have been synthesized by reaction of bis(2‐pyridylimino)isoindole derivatives with the corresponding metal(II) acetates. Reaction of 1‐6 with 1.5 ‐ 2 molar equivalents of t‐BuOOH gave the corresponding alkylperoxocobalt(III) complexes [Co(BPI)(OAc)(OOtBu)] (10 ‐ 15). Using an aqueous solution of t‐BuOOH (70 %), cyclohexene was selectively catalytically oxidized to the dialkylperoxide cyclohex‐2‐ene‐1‐t‐butylperoxide.     

Chemically characterised Pimenta dioica (L.) Merr. essential oil as a novel plant based antimicrobial against fungal and aflatoxin B1 contamination of stored maize and its possible mode of action

Abstract

The chemical characterisation of Pimenta dioica essential oil (PDEO) revealed the presence of 50 components, amongst which α-Terpineol (30.31%) was the major component followed by β-Linalool (6.75%) and γ-Terpinene (4.64%). The oil completely inhibited the growth of aflatoxin B₁ secreting strain Aspergillus flavus LHP-VS-8 and aflatoxin B₁ production at 2.5?µL/mL and 1.5?µL/mL, respectively. The oil caused dose dependent reduction of methylglyoxal (an AFB₁ inducer), enhanced leakage of Ca²⁺, Mg²⁺ and K⁺ ions and significantly reduced ergosterol content of fungal plasma membrane. During in situ experiments, PDEO exhibited complete protection of fumigated maize cob slices from fungal infestation without affecting seed germination. The chemically characterised PDEO is recommended as a plant based preservative and shelf life enhancer of food commodities by preventing fungal growth, AFB₁ production and lipid peroxidation. This is the first report on PDEO as inhibitor of AFB₁ secretion and methylglyoxal biosynthesis.     

Synthesis and pharmacological evaluation of 3-diphenylmethyl-6-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles: A condensed bridgehead nitrogen heterocyclic system

A series of 3-diphenylmethyl-6-substituted-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole derivatives (4a–j and 5a–d) were synthesized by condensation of 4-amino-5-diphenylmethyl-4H-1,2,4-triazole-3-thiol with various substituted aromatic acids and aryl/alkyl-isothiocyanates. The structures of synthesized compounds were characterized by elemental analysis, IR, ¹H NMR, ¹³C NMR and mass spectroscopic studies. These compounds were tested in vivo for their anti-inflammatory activity. The compounds which showed activity comparable to the standard drug ibuprofen were screened for their analgesic, ulcerogenic, lipid peroxidation and hepatotoxic effects. Compounds 6-(4-chlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole (4a) and 6-(2,4-dichlorophenyl)-3-diphenylmethyl-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazole(4c) emerged as the most active compounds of the series and were moderately more potent than the standard drug ibuprofen.     

铜掺杂钙铝水滑石催化氧化异丙苯制备异丙苯过氧化氢

采用共沉淀法制备了铜掺杂钙铝水滑石Ca₄Cu _x Al-LDHs（x=0,0.1,0.3,0.5,0.8,1.0）,并对其催化异丙苯液相氧化制备异丙苯过氧化氢的活性进行了研究。采用X射线衍射、傅里叶红外光谱、扫描电子显微镜和热分析等手段对Ca₄Cu _x Al-LDHs进行了表征,制备的Ca₄Cu _x Al-LDHs保留了水滑石的片层状结构,铜的掺杂使孔径变小,比表面积增大。当进料比（催化剂/异丙苯）为7.5 mg/mL,反应温度85 ℃,氧气流速为15 mL/min,反应时间7 h,异丙苯的转化率为34.5%,异丙苯过氧化氢的选择性为86.9%,催化剂循环使用5次后,异丙苯的转化率为31.2%,异丙苯过氧化氢的选择性为83.3%。研究为异丙苯过氧化氢开发了新的催化体系。     

Screening of anti-inflammatory and antioxidant potential of functionalized tetrahydrocarbazole linked 1,2-diazoles and their docking studies

Inflammatory diseases are associated with life-threatening syndromes like hepatitis, cancer, and trauma injury while some decrease the quality of life such as rheumatism, arthritis, and tuberculosis. 1,2-Diazoles (pyrazolines) play a vital role in COX-2 inhibition thus dinitro-tetrahydrocarbazole linked pyrazolines have been synthesized and endeavor to screen for anti-inflammatory, antioxidant and molecular docking studies. For this purpose, 6,8-dinitro-acetyl-2,3,4,9-tetrahydrocarbazole (I), aromatic aldehydes (IIa-e) and hydrazines (IIIa-b) were combined via multicomponent reaction approach under the influence of microwave irradiations to afford pyrazolines (1–10). All new molecules were screened for in vitro anti-inflammatory activity by human red blood cells membrane stabilization, antioxidant potential by2,2-diphenyl-1-picrylhydrazyl,2,2´-azinobis (3-ethylbenzo thiazoline)-6-sulphonic acid, lipid peroxidation, and total antioxidant capacity assays along with cytotoxicity by brine shrimp lethality assay. Molecular docking was performed by using the Auto Dock program. Both disubstituted and trisubstituted diazoles showed excellent membrane stabilizing effects, (91.89 % and 77 %, respectively). The presence of phenol, furan, thiocarbamide, and chloro-moieties have the most prominent effect. Toxicity results indicated that compounds were less toxic at the tested dose (0.1 mg/ml). The antioxidant study showed that compound 2 was more active showing low IC₅₀ values (32.2 and 39.2 µg/ml) in DPPH and total phenolic contents assays respectively. Compound 3 (44.0 µg/ml) showed the highest potential assay in ABTS radical neutralization assay while compound 7 (65.0 µg/ml) showed maximum potential in lipid peroxidation. All diazoles (1–10) were screened for in vitro anti-inflammatory potential where disubstituted diazoles were found better than trisubstituted analogs and exhibited significant antioxidant potential. Molecular docking of diazoles showed a good correlation of their anti-inflammatory activity with p38α MAPK, COX-2, and 5-LOX enzymes that are molecular therapeutic targets of inflammation.