New azo derivatives of gossypol

New azo derivatives of gossypol are described. Their physicochemical properties are reported. The presence of hydroxyazo- and quinonhydrazo-tautomers is proposed.A. S. Sadykov Institute of Bioorganic Chemistry, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (99871) 162 70 71. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 145–148, March–April, 2000.     

Synthesis of porous divinylbiphenyl copolymers and their sorptive properties towards phenol and its derivatives

Seven porous divinylbiphenyl polymers having the same nominal crosslinking degree (51.8 wt.%) have been synthesized using suspension polymerization method in the presence of the following inert diluents or their mixtures: toluene, heptane, dodecane, isooctane. The use of various inert diluents was aimed at changing the extent of polymeric network-diluent interactions. The obtained polymers have specific surface area in the range 50-300 m²/g depending on the type and amount of inert diluents used during polymerization. Their sorptive properties have been studied using dilute (0.5 mmol/l) aqueous solutions of phenol and its derivatives (2-chlorophenol, 2,4-dichlorophenol, 2,4,5-trichlorophenol, 2,6-dimethylphenol, 4-hydroxyphenol). It has been found that sorption, at low equilibrium concentration, follows the order: 2,4,5-trichlorophenol > 2,4-dichlorophenol > 2-chlorophenol > 2,6-dimethylphenol > phenol > 4-hydroxyphenol. Full characteristic of the porous structure of polymers has been obtained by nitrogen adsorption at 77K.     

Synthesis of porous vinylnaphthalene/divinylnaphthalene copolymers and their sorptive properties towards phenol and its derivatives

Four porous vinylnaphthalene/divinylnaphthalene (VN/DVN) polymers having three different nominal crosslinking degrees (60, 80 and 100 wt.%) have been synthesized using the suspension polymerization method in the presence of toluene and decane.The use of various crosslinking levels and inert diluents was aimed at changing the extent of polymeric network-diluent interactions. The resultant polymers have specific surface area in the range 450-700 m²/g depending on the DVN content. Two sets of pores were detected in all resins: one with the diameter of ≈2 nm and the second one in the range of 30-40 nm. Their sorptive properties have been studied using dilute (0.5 mmol/l) solutions of phenol and its derivatives (o-chlorophenol, 2-methylphenol, o-nitrophenol, m-nitrophenol and p-nitrophenol). It has been found that sorption, at low equilibrium concentration, follows the order: o-nitrophenol > o-chlorophenol > m-nitrophenol > o-methylphenol > p-nitrophenol > phenol. Full characteristics of the porous structure of resultant polymers was obtained by nitrogen adsorption at 77 K and their surface properties analyzed using Inverse Gas Chromatography.     

Biological activity of gossypol and its derivatives

This review of the literature and of the authors' own investigations is devoted to the biological activity of gossypol and its derivatives. Certain results of the structural—functional analysis of gossypol ethers and the products of its condensation with amines and CH-acids are discussed. The results of pharmacokinetic investigations of radioactively labeled samples of gossypol and its physiologically active derivatives are given.     

Antioxidant activity and kinetics studies of eugenol and 6-bromoeugenol

In this work, we report the antioxidant and free radical scavenging activity of 6-bromoeugenol and eugenol. EC₅₀, the concentration providing 50% inhibition, is calculated and the antioxidant activity index (AAI) is evaluated. The antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method. EC₅₀ values of 6-bromoeugenol, ascorbic acid and eugenol were 34.270 μg/mL, 54.888 μg/mL and 130.485 μg/mL, respectively. 6-Bromoeugenol showed higher AAI value (1.122) followed by ascorbic acid (0.700), then by eugenol (0.295). We also investigate the kinetics of DPPH radical scavenging activity of our products to determine the useful parameter TEC₅₀ to evaluate their antiradical efficiency (ARE). Our results have shown high ARE. This study has provided the following ARE ( × 10^? 3) order for the tested antioxidants: ascorbic acid (70.119)>6-bromoeugenol (34.842) > eugenol (21.313). Finally, we classify ascorbic acid and eugenol as fast kinetics reaction (TEC₅₀ 8.82 and 11.38 min, respectively) and 6-bromoeugenol as medium kinetics reaction (TEC₅₀ 39.24 min).     

Biological activity of gossypol and its derivatives

This review of the literature and of the authors' own investigations is devoted to the biological activity of gossypol and its derivatives. Certain results of the structural—functional analysis of gossypol ethers and the products of its condensation with amines and CH-acids are discussed. The results of pharmacokinetic investigations of radioactively labeled samples of gossypol and its physiologically active derivatives are given.A. S. Sadykov Institute of Bioorganic Chemistry of the Academy of Sciences of the Uzbekistan Republic, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 334–349, May–June, 1993.     

Chemiluminescence determination of melatonin and some of its derivatives using potassium permanganate and formaldehyde system

It was found that melatonin and its derivatives, such as N-acetyl- 5-methoxytryptamine (MT), N-acetyl-5-hydroxytryptamine (NAS), 5-Methoxytrypt- amine (5-MT), 5-Methoxyindolyl acetic acid (5-MIAA) and N-acetyl-5-methoxy- 6-hydroxytryptamine (6-HMT) would give chemiluminescence in the acidic potassium permanganate solution, and formaldehyde would enhance this chemiluminescent reaction greatly. The optimum conditions for this chemiluminescent reaction were studied in detail by a flow injection system. A new simple rapid method has been developed under the optimum conditions for determination of melatonin. This method has the advantages of high sensitivity, wide range of linear response and low detection limit. On the basis of investigation of chemiluminescent, fluorescent and UV spectra of melatonin in acidic solution containing potassium permanganate and formaldehyde, a possible mechanism of this reaction was proposed.     

肼及其衍生物在固体电极上的直接电化学行为研究

肼及其衍生物被广泛应用于医药,化工,军事,航天等领域,并被用作推进剂,水处理剂,农药,医药,燃料电池,光稳定剂以及化工生产助剂等诸多方面。因此对肼及其衍生物的研究和开发有着极其重要的理论意义和应用价值。本文研究了肼(Hydrzdine,DH),苯肼(Phenylhydrazine,PH),对硝基苯肼(p-Nitrophenykhzille,PNPH)和2,4-二硝基苯肼(2,4-DinitrophenyIhydrazine,DPH)在固体玻碳电极和铂电极上的不可逆电化学氧化行为,     

壳聚糖及其衍生物递送miRNA/siRNA的研究进展

微小RNA(microRNA,miRNA)和短链干扰RNA (small interfering RNA,siRNA)是两类具有调节基因表达功能的内源性非编码性小RNA分子.它们已成为多种疾病的潜在治疗药物,逐渐被应用于基因治疗中,而将小RNA应用于基因治疗亟需一种安全高效的递送载体.壳聚糖及其衍生物作为一种可降解、低...     

Liquid structure of benzene and its derivatives as studied by means of X-ray scattering

The liquid structures of benzene, toluene, aniline, benzaldehyde and nitrobenzene were investigated by the X-ray scattering method. The X-ray scattering data were analysed by a method without constructing any structure models. The obtained liquid structure of benzene is different from the previous X-ray scattering results which were derived from the quasi-lattice structure for the liquid based on the crystal structure of benzene. This is because a molecular arrangement which is not found in the crystal structure is left out of consideration. In liquid toluene, benzaldehyde and nitrobenzene, two molecules are associated with the dipole–dipole interaction in the antiparallel fashion. Two aniline molecules are hydrogen-bonded in liquid aniline. The third molecule weakly interacts with the other two in liquid toluene, aniline and benzaldehyde. In liquid nitrobenzene, the parallel dipole–dipole interaction of the third molecule with another one is present in the coplanar form. The substituent effect on the liquid structures is discussed.     

Synthesis and antifungal activity of trichodermin derivatives

<正>A series of derivatives were synthesized from trichodermin(1) which was an antifungal metabolite produced by Trichoderma taxi sp.nov.Their structures were confirmed by ~1H NMR,MS spectrum.Their antifungal activities were evaluated in vitro.The preliminary structure activity relationships(SAR) results indicated that the double bond,epoxide moiety and ester group were main pharmacophore elements,the stereochemistry of C4 position played a key role as well,and the compounds 1e-1g displayed stronger antifungal activity against Magnaporthe grisea than 1.     

二苯乙烯衍生物的合成及抗肿瘤活性

以甲氧基取代的4’-氨基二苯乙烯与4-溴甲基-5-甲基-1,3-二氧杂环戊烯-2-酮为原料,通过亲核取代反应合成得到了4种新的二苯乙烯衍生物。这些化合物的结构经NMR、IR和元素分析确定。以HeLa、SMMC-7721、BGC-823和A549为受试细胞株,用MTT法测试了这4种化合物的抗肿瘤活性。测试结果表明,这些化合物具有一定的抗肿瘤活性。     

Thermophysical properties of sulfur heterocycles: Thiane and thiophene derivatives

The present study reports a DSC study of the sulfur heterocyclic compounds: 2,2’-bithiophene [492-97-7]; 2,5-thiophenedicarboxylic acid [4282-31-9]; 3-acetylthiophene [1468-83-3]; 2-thiopheneacetic acid [1918-77-0]; 3-thiopheneacetic acid [6964-21-2]; 1,4-dithiane sulfone [139408-38-1]; 1,3-oxathiane-3,3-dioxide (1,3-oxathiane sulfone) [109577-03-9] and 1,4-oxathiane-4,4-dioxide (1,4-oxathiane sulfone) [107-61-9] in the temperature interval T = 268 K and the melting temperatures. Temperatures, enthalpies and entropies of fusion are reported. 1,4-Oxathiane sulfone presents solid-solid phase transitions near to fusion. No additional solid-solid phase transitions were observed for the other solid compounds. For the compounds that are solids over the temperature interval, the heat capacity of the condensed phase was measured. Heat capacities at T = 298.15 K for the liquids 2-acetylthiophene [88-15-3]; methyl, 2-thiopheneacetate [19432-68-9]; methyl, 3-thiopheneacetate [58414-52-1] and thiazole [288-47-1] were also measured. The C_p,m (298.15 K) values obtained in this work were compared with the available experimental data and with values estimated with group contribution schemes.     

Electrochemical behavior of tryptophan and its derivatives at a glassy carbon electrode modified with hemin

The electrochemical behavior of tryptophan (Trp) and its derivatives, such as indole-3-acetic acid (IAA), 5-hydroxytryptamine (5-HT), 5-hydroxy-indole-3-acetic acid (5-HIAA) and glycyl-tryptophan (Gly-Trp) peptide at a glassy carbon electrode modified with hemin (hemin/GC electrode) by electropolymerization have been investigated in detail. The results showed that the hemin/GC electrode would catalyze the electrochemical oxidation of Trp and its derivatives, based on which a differential pulse voltammetric procedure has been proposed for determination of Trp and its derivatives. Meanwhile, the electrochemical reaction mechanism for these compounds at hemin/GC electrode has been also investigated, and the results indicated that a two electron and two proton transfer was involved in the electrode reaction process.     

Synthesis of (bis-Dimethylaminoethylimino)gossypol and Its Associate with Polyvinylpyrrolidone and Their Effect on Protein Biosynthesis in Rat Liver with Acute Hepatitis

(Bis-dimethylaminoethylimino)gossypol and its associate with PVPwere synthesized. Their effects on in vitro and in vivo synthesis of cytoplasmic proteins in rats with acute heliotrinic hepatitis were studied. It was found that heliotrine intoxication substantially suppresses the incorporation of labeled amino acids into cytoplasmic proteins. Administration of gossypol derivativesrestored markedly the activity of the hepatocytic protein-synthesizing system.     

苯二氮杂卓类化合物的合成及抗血吸虫活性研究

化合物B30属于苯二氮杂卓类化合物.体外实验表明,在50μM具有100％的杀灭血吸虫效果.本文利用药物化学生物电子等排等原理,设计、合成了4个B30衍生物6、10、13、16,并对其抗血吸虫活性进行初步体外评价.结果显示4个化合物均具有一定的杀虫能力.尤其化合物16有较好的抗血吸虫活性,在50μM浓度下血吸虫的存活率降...     

First principles investigation on the key factors of broad absorption spectra and electronic properties for oligothiophene and its derivatives for solar cells

On the basis of optimized structures of two kinds thiophene oligomers, we investigated the configuration and conformation dependent optical and electronic properties of α or β substituted oligothiophene (PT) and oligo(thienylenevinylene) (PTV) isomers, respectively, at the TD‐DFT/6‐31+G(d,p)//PBE0/6‐31G(d) level. The corresponding properties of polymers were predicted by extrapolation method. The broad absorption regions for polythiophene and/or poly(thienylenevinylene) can be ascribed to the coexistence of various conformational and/or configurational isomers with similar energies and each corresponding excited state possessing different absorption spectrum and overlapping each other. Furthermore, the reorganization energies for electron (λ_e) and hole (λ_h) of α or β substituted PTV and PT indicate them to be potential ambipolar charge transport materials under the proper operating conditions. Therefore, these results are important because they can provide a rational way for the design of multifunctional materials with broad absorption and ambipolar charge transport properties for solar cells devices. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011     

Synthesis and antifungal activity of chalcone derivatives

In the present study, using chalcone as a lead compound, a series of its derivatives (compounds 1–30) were designed and synthesised. Their activity of anti-pathogenic fungi of plants has been evaluated. It is found that these compounds have good antifungal activity against Sclerotinia sclerotiorum, Helminthosprium maydis, Botrytis cinerea, Rhizoctonia solani and Gibberella zeae. Among them, the inhibition of growth for compound 30 against S. sclerotiorum showed 89.9%, with the median effective concentrations (EC₅₀) of 15.4 μg mL^? 1. The inhibition of growth for compounds 28, 29 and 30 at a concentration of 100 μg mL^? 1 against H. maydis is 90.3%, 90.7% and 91.1%, with EC₅₀ of 15.1, 18.3 and 18.1μg mL^? 1, respectively.     

氮杂岩白菜素衍生物的合成及其初步抗肿瘤活性

岩白菜素因其广泛的生理活性而备受关注。本文通过Mannich和Mitsunobu反应,合成了8个氮杂岩白菜素衍生物,其结构经1H NMR、13C NMR及质谱确证。采用MTT法初步测试了目标化合物体外抗肿瘤活性,结果表明,化合物3c和3d对细胞株A549均表现出优于岩白菜素的抑制活性(IC50分别为3.74μmol/L和5.05μmol/L),可做进一步研究。