SYNTHESIS OF 3,4-DIPHENYL-1.3,4-DIAZAPHOSPHOLID1N-2-ONE-4-OXIDE BY MANNICH-TYPE REACTION

Phenylurea reacted with dichlorophenylphosphine and aldehydes or ketones by Mannich-type reaction in anhydrous benzene to give five-mem- bered phosphorous heterocyclic compounds.However.derivatives of α-ureidoalkylphosphonic acids were obtained as the reaction performed in glacial acetic acid.

Synthesis and Crystal Structure of 1,2-Dis(1,3-diphenylpropan-2-yl)disulfane

A novel compound of 1,2-dis（1,3-diphenylpropan-2-yl）disulfane（C30H30S2,Mr=454.27）was synthesized in ethanol with 1,3-diphenyl-2-propanone as raw materials,giving high yield of product（90%）.Its structure was determined by IR,1H NMR,MS,elemental analysis and X-ray diffraction.The crystal belongs to monoclinic,space group C2 with a=18.727（3）,b=6.5179（9）,c=13.7576（18）,β=131.0610（10）o,V=1266.2（3）3,Z=2,Dc=2.136 g/cm3,μ=1.078 mm-1,F（000）=843,R=0.0490 and wR=0.1247 for 3211 observed reflections with I2（I）.X-ray analysis reveals that the molecule is not symmetrical.There exist no classical hydrogen bonds andπ-πstacking interactions.Moreover,the thermal stability of compound 3 was investigated.

Antioxidant Activity Evaluation in a Series of Heterocyclic Compounds Derived from 1,8-Diaminonaphthalene

From (2,3-dihydro-1H-perimidin-2-yl)-phenyl, the substitution of OH group in ortho or para position on the phenyl ring, allows us to synthesize the studied compounds. These three compounds have been characterized by conventional spectroscopic methods (NMR and MS). The interest of this work is to review the antioxidant activity of our compounds. The antioxidant activity screening carried out according to FRAP and DPPH methods revealed significant anti-free radical properties for compounds 1 and 2 even at low concentrations. In contrast to the compound 2, compound 3 for which the OH group is substituted in para position has the lowest activity in both cases. Therefore the para position seems to be the least sensitive position to increase the antioxidant activity of this pharmacophore.

几种天然黄酮类化合物对二苯代苦味肼自由基的清除作用

采用循环伏安法、示差脉冲伏安法对四种天然黄酮类化合物清除二苯代苦味肼自由基(DPPH)的能力进行了探讨.研究表明:此法可直接观测样品对DPPH的清除作用,而且灵敏度高、准确可靠,是一种检测自由基及物质对其清除作用的有效方法.

Synthesis of a New β-Mercaptoalcohol

In this letter, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol was synthesized from L-valine and two synthetic routes have been tried.

A Comparative Study of Antioxidant Activities between Fresh and Dry Mushrooms in the Genera <i>Cantharellus</i>and <i>Afrocantharellus</i>from Tanzania

Cantharellus and Afrocantharellus mushrooms are widely consumed in both fresh and dry forms. However, their antioxidant and whether their values changing with drying processes are not known. This study establishes their values and the effect of sun drying on their quality and quantity. Methanolic extracts of five Cantharellus and two Afrocantharellus species were investigated. The investigation used (1,1-diphenyl-2-picrylhydrazyl radical) DPPH as a substrate to determine radical scavenging abilities. Further quantitative analyses for carotenoids, flavonoid, total phenolic compounds and vitamin C content were done using spectrophotometric assay at 515 nm. Comparatively, fresh mushroom had higher vitamin C and Lycopene contents than their dry counterparts with β-carotene. Flavonoid and phenolic compounds were higher in dry forms than those in their fresh counterparts. Radical scavenging ability also varied with fresh forms depicting higher activity compared to dry forms. The variation was low in Afrocantharellus species (0.8% and 0.99%) while it was higher in Cantharellus species (24.12% and 7.52%). The highest ability was observed in fresh forms of Cantharellus pseudocibarius (EC50 50 = 0.4 mg/ml) was from dry form of Cantharellus rufopunctatus. This shows that studied mushrooms are rich in antioxidants and their quality and quantities are affected differently in both forms. Both dry and fresh mushrooms are potential sources of natural antioxidants. The portrayed high scavenging ability by these mushrooms envisages promoting them into potential nutraceutics.

The Application of Novel Electrochemical Approach to Antioxidant Activity Assay of Metal Porphyrins with Bulky 3,5-Diisobornyl-4-hydroxyphenyl Moieties

The complexes of biogenic metals (Zn2+,Cu2+,Co2+,Mn3+,Fe3+) based on meso-tetra(3,5-diisobor- nyl-4-hydroxyphenyl)porphyrin 1 were synthesized. The electrochemical behavior of these com-pounds was studied using cyclic voltammetry (CV) and rotating disk electrode (RDE) techniques. The antioxidant activity of complexes was estimated by means of the electrochemical assay based on the hydrogen atom transfer reaction to the stable radical 2,2’-diphenyl-1-picrylhydrazyl (DPPH). The RDE method was applied for this process monitoring. It was shown that the efficiency of the metal complexes (Cu2+,Co2+,Mn2+,Ni2+,Fe3+) is practically the same order as that of free base porphyrin 1. However the Zn2+ complex demonstrates significantly higher antioxidant activity, and the stoichiometry of the reaction was determined as σ = 4. The results demonstrate that porphyrin macrocycle can directly affect the antioxidant properties of 2,6-diisobornylphenol.

Effect of Induced Mutation on Antioxidant Activity in Ocimum basilicum Linn

Five batches from the same stock of seeds of Ocimum basilicum were irradiated at 5, 10, 15, 20 and 25 Gy, respectively using 60C source. Methanolic leaf extracts of these samples and a control were evaluated for their antioxidant activity by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging method using M2 plants. All the methanolic extracts showed antioxidant activity. The IC50 of the methanolic extracts of the six different treatments, control, 5 Gy, 10 Gy, 15 Gy, 20 Gy and 25 Gy, showed antioxidant activity with IC50 values of 100, 90, 86, 61, 71 and 70 μg/ml, respectively. Three individual mutants, M-15-5, M-20-6 and M-15-4, had IC50 values of 26, 30 and 40 μg/ml, respectively. These mutants were from the 15 Gy and 20 Gy treatments. From the results, it is confirmed that induced mutation can be employed to create variation in the levels of free radical scavenging activity in O. basilicum and can therefore serve as a tool for breeding for high levels of antioxidant activity in O. basilicum.

Comparison of Antioxidant Activities of Silver Nanoparticles and Methanol Extracts of Three Indigenous Nigeria Herbal Seeds

The antioxidant of seeds was carried out using extracts from methanol and Silver Nanoparticles from the spice. The SEM shows the shapes, dispersion and agglomeration of the sample, while the EDX confirms the SEM and the presence of some compounds. The FT-IR reveals the AgNPs capping and reducing the particular biomolecule from the functional group for identification. Compounds found in the FT-IR seeds of Capsicum annum are Ag L (Silver iodide), C K (Cyanogen chloride), P K (Phenol). Monodora myristica are Mo L (Molybdenum), Ag L (Silver iodide), C K (Cyanogen chloride), P K (Phenol), Mg K (Magnesium). Piper guineense are Ag L (Silver iodide), Ci K (Potassium chloride), C K (Cyanogen chloride), P K (Phenol). The seeds show that the AgNPS of CA and MM has a better antioxidant activity than the methanol of CA and MM, while the PG methanol has a better activity than the AgNPS PG. The control (Catechin and Galic acid) has a slight overall better DPPH activity than the AgNPS. It is important to note that there is a concentration dependency in CA, MM AgNPS, PG methanol respectively. Notably, at CA methanol, the conc. at 125 was higher than the conc. at 250. Hence, there is need to create a great part in using plant samples for making tabulated or capsulated drugs for treatment of diseases and using plant silver nanoparticles to develop a healthy food/drug preservative package material “smart packaging” that will enhance shelf-life.