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111.
Omar Sarheed Manar Dibi Kanteti V. R. N. S. Ramesh Markus Drechsler 《Molecules (Basel, Switzerland)》2021,26(9)
Transdermal drug delivery of lidocaine is a good choice for local anesthetic delivery. Microemulsions have shown great effectiveness for the transdermal transport of lidocaine. Oil-in-water nanoemulsions are particularly suitable for encapsulation of lipophilic molecules because of their ability to form stable and transparent delivery systems with good skin permeation. However, fabrication of nanoemulsions containing lidocaine to provide an extended local anesthetic effect is challenging. Hence, the aim of this study was to address this issue by employing alginate-based o/w nanocarriers using nanoemulsion template that is prepared by combined approaches of ultrasound and phase inversion temperature (PIT). In this study, the influence of system composition such as oil type, oil and surfactant concentration on the particle size, in vitro release and skin permeation of lidocaine nanoemulsions was investigated. Structural characterization of lidocaine nanoemulsions as a function of water dilution was done using DSC. Nanoemulsions with small droplet diameters (d < 150 nm) were obtained as demonstrated by dynamic light scattering (DLS) and cryo-TEM. These nanoemulsions were also able to release 90% of their content within 24-h through PDMS and pig skin and able to the drug release over a 48-h. This extended-release profile is highly favorable in transdermal drug delivery and shows the great potential of this nanoemulsion as delivery system. 相似文献
112.
Vijayakumar Uppar Sandeep Chandrashekharappa Chandan Shivamallu Sushma P Shiva Prasad Kollur Joaquín Ortega-Castro Juan Frau Norma Flores-Holguín Atiyaparveen I. Basarikatti Mallikarjun Chougala Mrudula Mohan M Govindappa Banuprakash Jayadev Katharigatta N. Venugopala Belakatte P. Nandeshwarappa Ravindra Veerapur Abdulaziz A. Al-Kheraif Abdallah M. Elgorban Asad Syed Kiran K. Mudnakudu-Nagaraju Basavaraj Padmashali Daniel Glossman-Mitnik 《Molecules (Basel, Switzerland)》2021,26(9)
113.
114.
Kumar A. Kishore Sunitha V. Ramesh G. Jeshma K. 《Russian Journal of General Chemistry》2021,91(12):2546-2553
Russian Journal of General Chemistry - A series of novel 1,2,3-triazoles (8a–8m) were synthesized using click chemistry in excellent yields and were characterized by IR, NMR, MASS... 相似文献
115.
June Cyriac Justin Paulose Mathai George Marupaka Ramesh Ragampeta Srinivas Daryl Giblin Michael L. Gross 《Journal of the American Society for Mass Spectrometry》2014,25(3):398-409
ESI-protonated 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one (1) undergoes a gas-phase Nazarov cyclization and dissociates via expulsions of ketene and anisole. The dissociations of the [M + D]+ ions are accompanied by limited HD scrambling that supports the proposed cyclization. Solution cyclization of 1 was effected to yield the cyclic ketone, 2,3-bis-(2-methoxyphenyl)-cyclopent-2-ene-1-one, (2) on a time scale that is significantly shorter than the time for cyclization of dibenzalacetone. The dissociation characteristics of the ESI-generated [M + H]+ ion of the synthetic cyclic ketone closely resemble those of 1, suggesting that gas-phase and solution cyclization products are the same. Additional mechanistic studies by density functional theory (DFT) methods of the gas-phase reaction reveals that the initial cyclization is followed by two sequential 1,2-aryl migrations that account for the observed structure of the cyclic product in the gas phase and solution. Furthermore, the DFT calculations show that the methoxy group serves as a catalyst for the proton migrations necessary for both cyclization and fragmentation after aryl migration. An isomer formed by moving the 2-methoxy to the 4-position requires relatively higher collision energy for the elimination of anisole, as is consistent with DFT calculations. Replacement of the 2-methoxy group with an OH shows that the cyclization followed by aryl migration and elimination of phenol occurs from the [M + H]+ ion at low energy similar to that for 1. Figure
The role of methoxy group in the Nazarov cyclization of 1,5-bis-(2-methoxyphenyl)-1,4-pentadien-3-one in the gas-phase and condensed phase by June Cyriac, Justin Paulose, M. George, Department of Chemistry, Sacred Heart College, Thevara, Cochin, Kerala, India-682013., M. Ramesh, R. Srinivas, National center for Mass Spectrometry, IICT, Hyderabad, India. Daryl Giblin and Michael L. Gross, Department of Chemistry, Washington University in St.Louis, St.Louis, USA, MO 63130. 相似文献
116.
Satish Gaddam Harshavardhan Reddy Kasireddy Karnakar Konkala Ramesh Katla Nageswar Yadavalli Venkata Durga 《中国化学快报》2014,25(5):732-736
A simple and practical method for the synthesis of N-substituted-2-aminobenzothiazoles via a crosscoupling reaction of 2-iodo anilines with isothiocyanates is envisaged using nano copper oxide as a recyclable catalyst and Cs2CO3as a base in PEG-400,as a bio-degradable,reusable,inexpensive and nontoxic reaction medium,under ligand-free conditions.The present tandem process underlines environmental acceptability to access a wide range of N-substituted-2-aminobenzothiazoles in good to excellent yields. 相似文献
117.
Lay-Koon Goh Ravi Kiran Purama Kumar Sudesh 《Applied biochemistry and biotechnology》2014,172(3):1585-1598
Poly(3-hydroxybutyrate) [P(3HB)], a polymer belonging to the polyhydroxyalkanoate (PHA) family, is accumulated by numerous bacteria as carbon and energy storage material. The mobilization of accumulated P(3HB) is associated with increased stress and starvation tolerance. However, the potential function of accumulated copolymer such as poly(3-hydroxybutyrate-co-3-hydroxyvalerate) [P(3HB-co-3HV)] remained unknown. In this study, Delftia acidovorans DS 17 was used to evaluate the contributions of P(3HB) and P(3HB-co-3HV) granules during simulated exogenous carbon deprivation on cell survival by transferring cells with PHAs to carbon-free mineral salt medium supplemented with 1 % (w/v) nitrogen source. By mobilizing the intracellular P(3HB) and P(3HB-co-3HV) at 11 and 40 mol% 3HV compositions, the cells survived starvation. Surprisingly, D. acidovorans containing P(3HB-co-94 mol% 3HV) also survived although the mobilization was not as effective. Similarly, recombinant Escherichia coli pGEM-T::phbCAB Cn (harboring the PHA biosynthesis genes of Cupriavidus necator) containing P(3HB) granules had a higher viable cell counts compared to those without P(3HB) granules but without any P(3HB) mobilization when exposed to oxidative stress by photoactivated titanium dioxide. This study provided strong evidence that enhancement of stress tolerance in PHA producers can be achieved without mobilization of the previously accumulated granules. Instead, PHA biosynthesis may improve bacterial survival via multiple mechanisms. 相似文献
118.
Ramesh Kumar Banjare Manoj Kumar Banjare Sandhyarani Panda 《Journal of solution chemistry》2020,49(1):34-51
A comprehensive study the effect of acetonitrile (ACN) with four cationic surfactants, viz. tetradecyltrimethylammonium bromide (TTAB), cetyltrimethylammonium bromide (CTAB), cetylpyridinium chloride (CPC) and cetylpyridinium bromide (CPB) was made by using the conductivity, surface tension, fluorescence and FTIR techniques. Significant micellar, interfacial and thermodynamic properties were studied by the tensiometeric and conductivity methods. The critical micelle concentration (CMC), aggregation number (Nagg), and Stern–Volmer constants (Ksv) have also been studied by the steady state fluorescence method using pyrene as probe. The fluorescence study also supports the CMC results obtained from conductivity and surface tension. FTIR was used to ascertain that the strength of intermolecular interactions such as hydrogen bonding, ion–ion pair interactions and induced dipole interactions between the surfactants and ACN depend upon the head-group of the surfactants. The interaction of surfactants with ACN is energetically favorable and occurs via direct interactions between the surfactants and ACN. The results further revealed that the strength of interactions between the surfactants and ACN follows the order: TTAB > CTAB > CPC > CPB. 相似文献
119.
K. Kasi Amarnath Reddy Smriti Moi Ashwini Dolle Basavaprabhu Hosamani Kiran Krishnamurthy Sunita Prakash Srinivasarao Raghothama Konkallu Hanumae Gowd 《Helvetica chimica acta》2020,103(7):e2000062
Dimedone is the most widely used chemical probe for detection of cysteine sulfenic acid in peptides and proteins. The reaction of dimedone with cysteine sulfenic acid results in the formation of unique cysteine dimedone motif containing thioether bridge. Based on the structure of cysteine dimedone residue in polypeptide, a new building block of Fmoc-Cys(Dmd)-OH was developed for solid phase synthesis of peptide cysteine dimedone. Mass spectrometric sequencing of synthetic peptides have confirmed successful incorporation of cysteine dimedone in peptide chain using HBTU/HOBt as a coupling agent. The new method permits synthesis of peptides containing both cysteine thiol and cysteine dimedone in the same sequence which was difficult to achieve by conventional methods. The synthetic peptide of glutathione cysteine dimedone was used as a standard in probing the air-mediated oxidation of thiol to disulfide form of glutathione. The co-elution of standard peptide and reaction mixture of oxidation of glutathione in presence of dimedone using RP-HPLC have confirmed the formation of glutathione cysteine sulfenic as an intermediate in the air-mediated oxidation of glutathione. The synthetic peptides of cysteine dimedone may find application in the field of redox proteomics and generation of antibodies against modified cysteine residue. 相似文献
120.
Rambabu Sirgamalla Kurumanna Adem Sakram Boda Ashok Kommakula Suryam Neradi Shyam Perka Kiran Bojja Mohammed Arifuddin 《Journal of heterocyclic chemistry》2020,57(9):3375-3383
We report herein DABCO mediated one pot synthesis of 2-(3-benzyl-2, 6-dioxo-3,6-dihydropyrimidin-1[2H]-yl)-N-(4-(1,3-dioxo-1H-benzo[de]isoquinolin-2[3H]-yl) aryl) acetamides ( 4a-j ). The silent features of this new one pot synthesis include the shorter reaction time, high yields, simple workup, and simultaneous formation of N-Amide and N-benzyl bonds in the one pot. The newly synthesized compounds ( 4a-j ) were characterized by different spectral techniques such as IR, 1H-NMR, 13C-NMR, HRMS. All the synthesized compounds were evaluated for their anti-bacterial and anti-fungal activities. The anti-bacterial activities results reveal that the compounds 4a , 4g , 4i , and 4j are most active against S. aureus. In the case of B. subtilis the compounds 4a , 4i , and 4j are found to be most active. The compounds 4c , 4e , 4i , and 4j are most active against E. coli. In the case of P. aeruginosa 4a , 4i & 4j are found to be more active. On the other hand, the anti-fungal activity result shows that the compounds 4d , 4f , 4i , and 4j are more active against A. niger. The compounds 4a , 4d , 4i , and 4j are found to be more active against C. albicans. 相似文献