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71.
Asha V. Chate Ankita S. Kulkarni Chetan K. Jadhav Amol S. Nipte Girabala M. Bondle 《Journal of heterocyclic chemistry》2020,57(5):2184-2193
In this article, we have developed a straightforward, easy and exceedingly competent approach for the synthesis of 5-phenyl-5,6-dihydropyrido[2,3-d]pyrimidine-2,4,7(1H,3H,8H)-triones obtain in superior yields in a sole reaction pace with an air and humidity steady catalyst in water as a green solvent at 100°C. The present procedure paves the approach for the synthesis of biologically fascinating molecular frameworks and has reward in conditions of little catalyst loading with palpable ambiguous and straightforward-to-do reaction circumstances with easy purification process. The used β-cyclodextrin catalyst was recuperated and repeated several times devoid of noteworthy loss of catalytic activity, which is a crucial parameter of green synthesis. 相似文献
72.
Acid phosphatase is ubiquitous in distribution in various organisms. Although it catalyzes simple hydrolytic reactions, it is considered as an interesting enzyme in biological systems due to its involvement in different physiological activities. However, earlier reviews on acid phosphatase reveal some fragmentary information and do not give a holistic view on this enzyme. So, the present review summarizes studies on biochemical properties, structure, catalytic mechanism, and applications of acid phosphatase. Recent advancement of acid phosphatase in agricultural and clinical fields is emphasized where it is presented as potent agent for sustainable agricultural practices and diagnostic marker in bone metabolic disorders. Also, its significance in prostate cancer therapies as a therapeutic target has been discussed. At the end, current studies and prospects of immobilized acid phosphatase are included. 相似文献
73.
Structural Chemistry - The current study primarily involves the investigation of reducing properties of dithia-substituted bicyclic hydrocarbons. Adiabatic electron affinities (AEA) of the selected... 相似文献
74.
Liquid crystalline supramolecular crosslinked polymer complexes of ditopic rylenebisimides and P4VP 下载免费PDF全文
Perylenebisimide and naphthalenebisimide (PBI‐PDP and NBI‐PDP) end functionalized with pentadecyl phenol is designed as ditopic hydrogen bonding acceptors to form supramolecular crosslinked network with poly(4‐vinyl pyridine) (P4VP). The pristine PBI‐PDP has been grown as single crystals from DCM‐MeOH (dichloromethane‐methanol) mixture at room temperature, which revealed a P21 space group. Noticeably, the pentadecyl alkyl chain shields the aromatic perylene core on both sides resulting in the absence of π–π interaction in single‐crystal assembly. The naphthalenebisimide derivative exhibits thermotropic liquid crystalline behavior, while both the molecules exhibits lyotropic liquid crystalline phases in tetrahydrofuran (THF), which were characterized using a combination of differential scanning calorimeter, X‐ray diffraction, and polarized light microscopy. The hydrogen‐bonded complex of both the rylenebisimides with P4VP preserves the mesomorphic properties in THF. The electron transport mobility measured by space charge limited current measurements reveals a two orders of magnitude increase in the charge transport in the P4VP complex compared to that of the pristine molecule. The average electron mobility obtained is μ e,avg: 10?3 cm2/Vs for P4VP‐PBI compared to μ e,avg: 10?5 cm2/Vs for pristine PBI derivative. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 951–959 相似文献
75.
76.
Transition Metal Chemistry - A cis-dioxidomolybdenum(VI) complex of a thiosemicarbazone of the type [MoO2L(DMSO)], where H2L?=?3-ethoxysalicylaldehyde-N4-(3-methoxyphenyl)... 相似文献
77.
Amol S. Nipate Chetan K. Jadhav Asha V. Chate Kanchan S. Taur Charansingh H. Gill 《Journal of heterocyclic chemistry》2020,57(2):820-829
An eco-friendly multicomponent synthesis of substituted imidazole derivatives catalyzed by β-cyclodextrin (β-CD) was scrutinized for the first time via a one-pot three-compound reaction of aldehyde, isatin, and ammonium acetate in H2O–EtOH at 80°C. β-CD is a supramolecule, highly efficient, biodegradable, and recyclable catalyst used to produce high yields of desired 1,8-dihydroimidazo[2,3-b]indoles. The developed protocol contains number of advantages like nontoxic, inexpensive catalyst; green reaction condition; easily available starting material; shorter reaction time; and good yields. 相似文献
78.
M. Asha Jhonsi 《Journal of luminescence》2009,129(8):854-860
Certain porphyrin derivatives namely meso-tetraphenylporphyrin (TPP), meso-tetrakis(4-carboxyphenyl)porphyrin (TCPP), meso-tetrakis(4-sulfonatophenyl)porphyrin (TSPP) were examined as sensitizers for colloidal CdS. The interaction of these porphyrins and colloidal CdS were studied by absorption, infrared, steady state and time resolved fluorescence spectroscopy and transient absorption techniques. The apparent association constants (Kapp) resulting from adsorption of porphyrins on CdS surface were calculated from both absorption and fluorescence studies and they agree well. Using all the spectroscopic measurements we confirmed that the interaction between porphyrins and colloidal CdS occurs through ground state complex formation and the quenching follows static mechanism. 相似文献
79.
Fifteen symmetric and unsymmetric 2,5-diamino benzoquinones have been synthesized and their electrochemical activity was studied by cyclic voltammetry. Presence of electron donating substituent like amino group found to shift the half wave potential towards more negative value which is more prominent in benzyl amino substituted amino benzoquinones (ABQs). All the compounds were checked for their anti-bacterial and anti-fungal activity by agar well diffusion technique. The more negative E1/2 values of benzyl amino substituted ABQs make them more active towards various bacterial and fungal speciesas is evident from MIC values. 相似文献
80.
Performance evaluation of nickel as anode catalyst for DMFC in acidic alkaline medium 《燃料化学学报》2018,46(5):592-599
Direct methanol fuel cell (DMFC) research is highly focused due to its high energy density, portability and inexpensive. In the present study conventional platinum catalyst used for methanol oxidation is being replaced with nickel catalyst supported over nickel mesh. The electrode is synthesized by single step electro deposition technique. Synthesized electrode was characterized by SEM, EDAX and AFM techniques to know the surface morphology, composition and thickness of the catalyst respectively. The electro catalytic behavior of the nickel for methanol oxidation was evaluated using cyclic voltammetry technique. As the DMFC is compatible with both the acidic and alkaline electrolytes the working of the nickel mesh electrode is analyzed in both media. The results showed maximum current density of 0.025 and 0.030 A/cm2 in alkaline and acidic medium respectively with less potential around 0.4 and 0.2 V. The other parameters such as varying the concentration of methanol, electrolyte medium, scan rate and thickness of the catalytic layer were analyzed and optimized. 相似文献