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181.
Anumula Rajini Muralasetti Nookaraju Ingala Ajit Kumar Reddy Venkatathri Narayanan 《Chemical Papers》2014,68(2):170-179
A novel vanadium dodecylamino phosphate was synthesised by an instant reaction between phosphoric acid and vanadyl acetylacetonoate using dodecylamine as the structure-directing agent at ambient temperature. The physicochemical characteristics of the material were investigated by a variety of analytical techniques. XRD studies revealed the presence of vanadium phosphate and hydrated vanadium phosphate phases in the framework of the material. The catalytic application of this material toward in the synthesis of polyhydroquinolines via Hantzsch condensation was investigated at ambient temperature. This method affords high yields within short reaction times. The influence of various reaction parameters such as different solvents, catalyst dosage, effect of aldehydes, and reusability was studied and a plausible mechanism proposed. 相似文献
182.
Rama Raju Baadhe Naveen Kumar Mekala Satwik Reddy Palagiri Sreenivasa Rao Parcha 《Applied biochemistry and biotechnology》2012,167(5):1172-1182
In this case study, we designed a farnesyl pyrophosphate (FPP) biosynthetic network using hybrid functional Petri net with extension (HFPNe) which is derived from traditional Petri net theory and allows easy modeling with graphical approach of various types of entities in the networks together. Our main objective is to improve the production of FPP in yeast, which is further converted to amorphadiene (AD), a precursor of artemisinin (antimalarial drug). Natively, mevalonate (MEV) pathway is present in yeast. Methyl erythritol phosphate pathways (MEP) are present only in higher plant plastids and eubacteria, but not present in yeast. IPP and DAMP are common isomeric intermediate in these two pathways, which immediately yields FPP. By integrating these two pathways in yeast, we augmented the FPP synthesis approximately two folds higher (431.16 U/pt) than in MEV pathway alone (259.91 U/pt) by using HFPNe technique. Further enhanced FPP levels converted to AD by amorphadiene synthase gene yielding 436.5 U/pt of AD which approximately two folds higher compared to the AD (258.5 U/pt) synthesized by MEV pathway exclusively. Simulation and validation processes performed using these models are reliable with identified biological information and data. 相似文献
183.
D. Bhaskar Reddy P. V. Ramana Reddy M. Muralidhar Reddy M. V. Ramana Reddy S. Vijayalakshmi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):325-329
Abstract Some new 1,1,2-trisubstituted ethylenic sulfones have been prepared by the condensation of aryl- and benzylsulfonylmethylsulfonylacetic acid esters with araldehydes. 相似文献
184.
G. V. P. Chandramouli B. Prasanna P. Naveen Kumar P. Vijayakumar Reddy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):511-522
The key step for the synthesis of 7-hydroxy 2,3-diarylsubstituted benzothiophenes 5a-f , by starting from substituted 2-aryl-2-((2-methoxy phenyl)thio)acetophenones 3a-f as an intermediate, consists of a Friedel-Crafts cyclization followed by demethylation by Lewis acids like BF 3 OEt 2 and AlCl 3 in DCM. 相似文献
185.
E-2-Penten-4-yn-1-ol (3) has been utilized as a source for 1,3-diene systems by employing lithium amide induced alkylation, and curpous iodide catalysed Grignard coupling reaction as key steps. Its application for the synthesis of (Z,E)-9,11-tetradecadienyl acetate and (E,E)-10,12-hexadecadienal is described. 相似文献
186.
Disulfide bond formation by the oxidative cleavage of thiol acetates and thiol esters using “Clayan”s under microwave irradiation is described. The non-metallic and inexpensive nature of the reagent are the important features of the procedure. 相似文献
187.
The synthesis and characterization of more than a hundred achiral compounds composed of banana-shaped molecules and belonging to eleven different homologous series are reported. All these symmetrical five-ring compounds are esters and are derived from resorcinol. The compounds have been systematically substituted by fluorine on the phenyl rings of the arms of these banana-shaped molecules. The mesophases exhibited by these compounds have been characterized using a combination of polarized light optical microscopy, differential scanning calorimetry and X-ray diffraction studies. Electro-optical investigations have been carried out on several compounds and both ferroelectric and antiferroelectric properties are observed. The influence of the position of the fluorine substituent on the nature of the mesophase obtained has been examined. 相似文献
188.
Pulla Reddy Singam Curt W. Bradshaw Jerome A. Menzia B. A. Narayanan Todd W. Rockway Noel Welch 《合成通讯》2013,43(14):2751-2756
An efficient process for the preparation of renin inhibitor, ABT-517 is described. The process avoids solvent extractions or chromatographic purifications and is used on multi-kilogram scale. 相似文献
189.
A concise approach for the total synthesis of attenols A and B is described involving MacMillan’s α-aminooxylation, Evan’s asymmetric alkylation, Brown’s allylation, and spiro-ketalization as key steps. This approach has successfully demonstrated the α-aminooxylation protocol for the construction of the anti-1,3-diol unit. 相似文献
190.
Rao Bolla Govinda Sudarsanam Putla Nallappareddy P. R. G. Yugandhar Reddy M. Venkateshwar Rao T. Reddy Benjaram M. 《Research on Chemical Intermediates》2018,44(10):6151-6168
Research on Chemical Intermediates - Selective allylic oxidation of cyclohexene was investigated over nanostructured CeO2/SiO2 and CeO2–Sm2O3/SiO2 catalysts synthesized by a feasible... 相似文献