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61.
Bhagyashri B. Kamble Tawade Anita K. Kamble Pravin Padavi Mukesh N. Sharma Kiran Kumar K. Ajalkar Balu D. Tayade Shivaji N. 《Russian Journal of Electrochemistry》2020,56(9):766-774
Russian Journal of Electrochemistry - A micro-bricks shaped tungsten oxide (WO3) was prepared by hydrothermal method. The prepared material was characterized by field emission scanning electron... 相似文献
62.
P. Madhavan B. M. Rao Pravin Abhishek P. R. Kumar M. Sreenivasulu K. B. Chandrasekhar 《Chromatographia》2007,65(1-2):81-84
A normal phase chiral LC method for chiral purity evaluation of β-amino-β-(4-methoxyphenyl) propionic acid was developed on
donor–acceptor (pirkle) column. The chiral stationary phase used was a 250 × 4.6 mm (R, R) Whelk-01 with 5 μm particle size,
which was accompanied with a 1 cm long guard column. The “hybrid” pi-electron donor–acceptor based stationary phase (R, R)
Whelk-01 was found to be enantiomeric selective for (R) and (S) enantiomers of β-amino-β-(4-methoxyphenyl) propionic acid
with a resolution >2.5. The concentration of 2-propanol and TFA in the mobile phase plays an important role on the chrmatographic
efficiency and resolution between the enantiomers. The limit of detection and limit of quantification of (S) enantiomer was
0.3 and 1.0 μg mL-1 for 20 μL injection volume. The percentage RSD of the peak area of six replicate injections of (S) enantiomer at LOQ concentration
was 4.5. The percentage recovery of (S) enantiomer from (R) enantiomer samples ranged from 92 to 100. The test solution was
observed to be stable up to 24 h after the preparation. The developed method was also checked by different analysts and on
different lots of columns, reagents and it was proved to be rugged. The developed normal phase chiral LC method can be used
for the determination of the enantiomeric purity of R-β-amino-β-(4-methoxyphenyl) propionic acid. 相似文献
63.
A convenient one-pot three-component method for the preparation of tetra-substituted thiophene derivatives has been developed. Reaction of acetyl acetone 1, phenyl isothiocynate 2 and 2-chloromethyl derivatives 3a–3c in the presence of potassium carbonate afforded the target compounds, namely ethyl2-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-2-oxoacetate derivatives 4a–4e, ethyl 3-(4-acetyl-3-methyl-5-(phenylamino)thiophen-2-yl)-3-oxopropanoate derivatives 4f–4i, di((4-acetyl-3-methyl-5-phenylamino)thiophen-2-yl)ketone derivatives 4j–4n in reasonable overall yields. The synthesized compounds were screened for antimicrobial activity. The detailed synthesis, spectroscopic data and antimicrobial activities of synthesized compounds were reported. 相似文献
64.
65.
The design and facile synthesis of a novel chiral six-membered PNA analogue (2S,5R )-1-(N-Boc-aminoethyl)-5-(thymin-1-yl)pipecolic acid, aepipPNA, that upon incorporation into PNA sequences effected stabilization of complexes with target complementary DNA. This is the first example where a six membered-PNA is shown to be capable of forming stable complexes with DNA and further expands the repertoire of cyclic PNA analogues. 相似文献
66.
Pravin C. Patil Dinesh S. Bhalerao Prasad S. Dangate Krishnacharya G. Akamanchi 《Tetrahedron letters》2009,50(42):5820-5822
Thioamides undergo oxidative dimerization on treatment with hypervalent iodine(V)-containing reagents, particularly o-iodoxybenzoic acid (IBX), in the presence of tetraethylammonium bromide (TEAB) to generate 3,5-disubstituted 1,2,4-thiadiazoles in excellent yield. 相似文献
67.
The limitations and factors affecting the hydride reduction of pyrrolo [1,4]benzodiazepine-5,10-diones to anthramycin-type analogs have been explored. 相似文献
68.
Pottabathula Srinivas Pravin R. Likhar Balsubramanian Sridhar Suresh Bhargava 《Journal of organometallic chemistry》2011,696(3):795-801
The synthesis and structure of palladium(II) complexes bearing uridato/pyridyl ligands as an anionic N-donor coordination sites are reported. The complexes have been shown to be highly active catalysts for the Heck reaction of aryl bromides (TON 4.0×104-9.1×104) and moderate activity for the activation of aryl chlorides under phosphine-free conditions. 相似文献
69.
An analysis is carried out to study the momentum, mass and heat transfer characteristics on the flow of visco-elastic fluid (Walter's liquid-B model) past a stretching sheet in the presence of a transverse magnetic field.In heat transfer, two cases are considered:
- 1.
- The sheet with prescribed surface temperature (PST case); and
- 2.
- The sheet with prescribed wall heat flux (PHF case).
70.
Pravin S. Bhale Babasaheb P. Bandgar Sakharam B. Dongare Sadanand N. Shringare Dnyaneshwar M. Sirsat 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):843-849
AbstractKetene dithioacetal mediated chemo- and regioselective synthesis of a series of novel 1,3,4,5-tetrasubstituted pyrazole derivatives (4a-l) integrated with a bioactive indole nucleus was achieved by reacting substituted 2-(1-methyl-1H-indole-3-carbonyl)-3,3-bis-(methylthio)-acrylonitrile (2) and substituted phenyl hydrazine hydrochloride (3) in the presence of a catalytic amount of anhydrous K2CO3 under reflux conditions. The structures were ascertained by 1H NMR, NOESY, 13C NMR, FT-IR, and HRMS data. In vitro cytotoxicity evaluation of the synthesized compounds against MCF 7 (breast carcinoma) and normal Vero (monkey kidney) cell lines revealed that the compound 5-(5-Bromo-1-methyl-1H-indol-3-yl)-1-(4-cyano-phenyl)-3-methylsulfanyl-1H-pyrazole-4-carbonitrile (4k) showed significant cytotoxicity against MCF 7 (GI50 = 15.6 µM) with low cytotoxicity against normal Vero cell line. Most of the synthesized compounds were also found to possess excellent anti-inflammatory and antioxidant (DPPH, NO, H2O2 and SOR) potential. 相似文献