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Reza Heydari Malek Taher Maghsoodlou Sayyed Mostafa Habibi-khorassani Nourallah Hazeri Farahnaz Barahuie Mohsen Rostamizadeh 《Arabian Journal of Chemistry》2010,3(4):229-232
Stable crystalline phosphorus ylides and 1,4-diionic organophosphorus compounds were obtained in good to excellent yields from the 1:1:1 addition reaction between triphenylphosphine, dialkyl acetylenedicarboxylates and β-dicarbonyl or heterocyclic compounds, such as diethyl malonate, acetyl acetone, 1,3-diphenyl propane-1,3-dione, 1,3-dimethylbarbituric acid, meldrum’s acid, 2-benzoxazolinone, benzotirazole, and 2-thiazoline-2-thiol in the presence of sodium dodecyl sulfate as a surfactant in water. Green synthesis, mild conditions, decreasing timescale of reaction, low cost, and easy workup are the main advantages of this method. 相似文献
83.
Fatemeh Ghodsi Sayyed Mostafa Habibi-Khorassani Mehdi Shahraki Saeedreza Emamian Mar Ríos-Gutiérrez Luis R. Domingo 《Tetrahedron》2019,75(19):2807-2816
The domino reactions of alkyne-tethered N-mesylhydrazones yielding fused polycyclic pyrazoles have been studied within the Molecular Electron Density Theory (MEDT). Analysis of the Gibbs free energies indicates that the more favourable reactive path is the one in which the elimination of mesylate anion takes place before the intramolecular [3 + 2] cycloaddition (IM32CA) reaction, which corresponds with the rate-determining step of these domino processes. ELF topological analysis of the bond formation along the IM32CA reaction indicates that in spite of the high activation energy associated to this intramolecular reaction, it shows a pmr-type mechanism characterised by the presence of a pseudoradical carbon at the phenyldiazomethane framework. 相似文献
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Ghalamkari Safoura Khosravian Farinaz Mianesaz Hamidreza Kazemi Mohammad Behjati Mohaddeseh Hakimian Sayyed Mohammadreza Salehi Mansoor 《Applied biochemistry and biotechnology》2019,187(3):975-983
Applied Biochemistry and Biotechnology - One of the most common somatic mutations in breast cancer is found in PIK3CA with a prevalence rate of 18–45%. Different variants of this gene are... 相似文献
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Malek Taher Maghsoodlou Sayyed Mostafa Habibi Khorassani Nourollah Hazeri Mohsen Rostamizadeh Seyed Sajad Sajadikhah Zahra Shahkarami Nariman Maleki 《Heteroatom Chemistry》2009,20(5):316-318
α‐Amino phosphonates were obtained in a one‐pot, simple, and efficient method from the reaction between aldehyde, aniline, trialkyl phosphite, and silica sulfuric acid as a catalyst in acetonitrile at room temperature. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:316–318, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20543 相似文献
86.
K.?A.?M.?Sayyed M.?S.?MetwallyEmail author M.?T.?Mohamed 《Southeast Asian Bulletin of Mathematics》2003,26(1):121-132
In this paper we introduce an estimation, namely, the upper bounds of the order and type, logarithmic order and logarithmic type and q-order and q-type of generalized Hadamard product of functions of the complex variables z. We append this study by getting a result concerning the subject of linear substitution. 相似文献
87.
Nosheen Akhtar Noshin Ilyas Humaira Yasmin R. Z. Sayyed Zuhair Hasnain Elsayed A. Elsayed Hesham A. El Enshasy 《Molecules (Basel, Switzerland)》2021,26(6)
Plant growth-promoting rhizobacteria (PGPR) mediate heavy metal tolerance and improve phytoextraction potential in plants. The present research was conducted to find the potential of bacterial strains in improving the growth and phytoextraction abilities of Brassica nigra (L.) K. Koch. in chromium contaminated soil. In this study, a total of 15 bacterial strains were isolated from heavy metal polluted soil and were screened for their heavy metal tolerance and plant growth promotion potential. The most efficient strain was identified by 16S rRNA gene sequencing and was identified as Bacillus cereus. The isolate also showed the potential to solubilize phosphate and synthesize siderophore, phytohormones (indole acetic acid, cytokinin, and abscisic acid), and osmolyte (proline and sugar) in chromium (Cr+3) supplemented medium. The results of the present study showed that chromium stress has negative effects on seed germination and plant growth in B. nigra while inoculation of B. cereus improved plant growth and reduced chromium toxicity. The increase in seed germination percentage, shoot length, and root length was 28.07%, 35.86%, 19.11% while the fresh and dry biomass of the plant increased by 48.00% and 62.16%, respectively, as compared to the uninoculated/control plants. The photosynthetic pigments were also improved by bacterial inoculation as compared to untreated stress-exposed plants, i.e., increase in chlorophyll a, chlorophyll b, chlorophyll a + b, and carotenoid was d 25.94%, 10.65%, 20.35%, and 44.30%, respectively. Bacterial inoculation also resulted in osmotic adjustment (proline 8.76% and sugar 28.71%) and maintained the membrane stability (51.39%) which was also indicated by reduced malondialdehyde content (59.53% decrease). The antioxidant enzyme activities were also improved to 35.90% (superoxide dismutase), 59.61% (peroxide), and 33.33% (catalase) in inoculated stress-exposed plants as compared to the control plants. B. cereus inoculation also improved the uptake, bioaccumulation, and translocation of Cr in the plant. Data showed that B. cereus also increased Cr content in the root (2.71-fold) and shoot (4.01-fold), its bioaccumulation (2.71-fold in root and 4.03-fold in the shoot) and translocation (40%) was also high in B. nigra. The data revealed that B. cereus is a multifarious PGPR that efficiently tolerates heavy metal ions (Cr+3) and it can be used to enhance the growth and phytoextraction potential of B. nigra in heavy metal contaminated soil. 相似文献
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Malek Taher Maghsoodlou Sayyed Mostafa Habibi Khorassani Nourollah Hazeri Mahmoud Nassiri 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):1363-1369
Stable crystalline phosphorus ylides were obtained in excellent yields from the 1:1:1 addition reaction between triphenylphosphine and di-tert-butyl acetylendicarboxylate, in the presence of antron, dimedone, indandion, and 3,5-dimethylbarbituric acid. These stable ylides exist in a solution as a mixture of two geometrical isomers as a result of restricted rotation around the carbon-carbon partial double bond resulting from conjugation of the ylide moiety with the adjacent carbonyl group. 相似文献
89.
Burhan Hamid Zaffar Bashir Ali Mohd Yatoo Fayaz Mohiddin Neesa Majeed Monika Bansal Peter Poczai Waleed Hassan Almalki R. Z. Sayyed Ali A. Shati Mohammad Y. Alfaifi 《Molecules (Basel, Switzerland)》2022,27(18)
More than 70% of our planet is covered by extremely cold environments, nourishing a broad diversity of microbial life. Temperature is the most significant parameter that plays a key role in the distribution of microorganisms on our planet. Psychrophilic microorganisms are the most prominent inhabitants of the cold ecosystems, and they possess potential cold-active enzymes with diverse uses in the research and commercial sectors. Psychrophiles are modified to nurture, replicate, and retain their active metabolic activities in low temperatures. Their enzymes possess characteristics of maximal activity at low to adequate temperatures; this feature makes them more appealing and attractive in biotechnology. The high enzymatic activity of psychrozymes at low temperatures implies an important feature for energy saving. These enzymes have proven more advantageous than their mesophilic and thermophilic counterparts. Therefore, it is very important to explore the efficiency and utility of different psychrozymes in food processing, pharmaceuticals, brewing, bioremediation, and molecular biology. In this review, we focused on the properties of cold-active enzymes and their diverse uses in different industries and research areas. This review will provide insight into the areas and characteristics to be improved in cold-active enzymes so that potential and desired enzymes can be made available for commercial purposes. 相似文献
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R. Z. Sayyed S. S. Shaikh S. J. Wani Md Tabish Rehman Mohammad F. Al Ajmi Shafiul Haque Hesham Ali El Enshasy 《Molecules (Basel, Switzerland)》2021,26(9)
The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost-effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 accumulates higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the Pseudomonas sp. RZS1 follows the Monod model more closely than A. faecalis RZS4. Both the cultures degrade their PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low-cost sources of nutrients for the growth and production of PHB and other metabolites. Their use would lower the production cost of PHB and the low-cost production will reduce the sailing price of PHB-based products. This would promote the large-scale commercialization and popularization of PHB as an ecofriendly bioplastic/biopolymer. 相似文献