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21.
Hetero Diels–Alder reaction of 3‐butyliminomethyl‐2‐aryl‐1H‐indoles (Schiff's base) 1 with p‐benzoquinone 2 affords six novel 5‐butyl‐11a‐aryl‐4a,5,11,11a‐tetrahydro‐11bH‐indolo[3,2‐c]quinoline‐1,4‐diones 3 in good yields. All the reactions proceeded with complete diastereoselectivity giving only one product in each case, which was characterized on the basis of its elemental analyses and spectral data (IR, 1H NMR, and Mass).  相似文献   
22.
In this communication, a simple and straightforward procedure for the heterocyclization of 1H‐4,5‐dihydro‐3‐(4‐haloaryl)‐5‐substituted phenylpyrazoles (4) with 1‐bromo‐3‐chloropropane and 2,3‐dibromo‐1‐(4‐fluoro‐3‐methylphenyl)‐3‐phe‐ nylpropanone affording 2,3,4,8,9‐pentahydro‐7‐(4‐haloaryl)pyrazolo[5,1‐e]benzo[1,5] oxazocines 5 and regioselective synthesis of 2,3(erythro),7,8‐tetrahydro‐2‐ aryl‐3‐(4‐fluoro‐3‐methylbenzoyl)‐6‐(4‐halophenyl)pyrazolo[5,1‐d]benzo[1,4]oxa‐ zepines 6, respectively, via solid–liquid PTC is reported. All the synthesized compounds have been characterized on the basis of their spectral studies (IR, PMR, and MS) and analytical data.  相似文献   
23.
Pleurotus sajor-caju, an edible mushroom, is a source of protein-rich food.Pleurotus sajor-caju has broad temperature (15–25‡C) and pH (4-6) optima for its growth, thus making it suitable for village-level applications, where it can be cultivated in a generally artificially uncontrolled environment. In the present investigations, the following agro-residues have been used for cultivation of this mushroom: paddy straw, wheat straw, bagasse,Cyamposis tetragonoloba, Sorghum vulgare, Pennesitum typhoideum, mango leaves, banana leaves,Zea mays, etc. and some residues mixed with other materials such as cotton seeds, fiscus fruits,Azadirachta indica leaves, etc. All the substrates (400 g) were pasteurized at 60‡C, soaked in water, packed in polythene bags, and inoculated with 8% wheat spawn on a dry weight basis. The cultivation was carried out for 2 months, during which four crops were harvested. The temperature was 10–25‡C and relative humidity was maintained at 80–90%. The maximum yields in percent of fruit bodies obtained were as follows: banana leaves, 125 (91.8), paddy straw, 124.2 (90.6), wheat straw, 111.7 (90),Sorghum vulgare, 108.8 (92.9),Cyamposis tetragonoloba, 108.3 (91.5), followed by others. The maximum yields in percent of fruit bodies obtained in combinations of some substrates were as follows: paddy straw + cotton seeds, 148.3 (91.3),Cyamopsis tetragonoloba + Azadirachta indica leaves, 105.8 (91.5),Sorghum vulgare + Azadirachta indica leaves, 103.8 (91.8); the figures in parentheses represent the percent moisture content. The biochemical changes effected as a result of mushroom growth in terms of utilization of cellulose, hemicellulose, and lignin were presented.  相似文献   
24.
Pleurotus sajor-caju grows efficiently and degrades all the components present in lignocellulosic residues. Production of cellulase and xylanase enzymes in submerged culture and during solid state cultivation has been studied. An initial pH of 5.0 was found to be optimal for the production of cellulase in shake flasks; this was attained in about 6–8 d in a medium containing either cellulose or rice straw as the sole source of carbon. On the cellulose medium, the maximum filter paper activity attained was 0.15 IU/mL in 7 d whereas the endoglycanase activity of 1.0 IU/mL, xylanase activity of 1.55 IU/mL, and Β-glucosidase activity of 0.57 IU/mL were acheived after 9 d fermentation. The reducing sugars were absent in the culture medium. The cellulases (filter paper activity and endoglucanases) were most active at pH 5.0 and 45‡C. Xylanase had maximum activity at pH 4.8 and 45‡C, and Β-glucosidase at pH 5.5 and 40‡C. In shake cultures,P. sajor-caju produced dispersed suspension of short mycelial threads and various sizes of pellets. The profile and extent of enzyme biosynthesis during submerged cultivation on rice straw was found to be of the same nature as obtained on cellulose. During solid state cultivation ofP. sajor-caju on rice straw beds for 36 d, the elaboration of enzyme activities did not appear to follow any definite pattern. However, filter paper activity, which is representative of cellulase action in hydrolyzing cellulose, remained more or less constant during the period of about the first 20 d of cultivation after the appearance of fruit bodies on the surface of rice straw beds. All the activities attained their minimum values after 23 d of cultivation, during which approximately 1 kg of fresh fruit bodies had been harvested. The total fruit bodies harvested till 36th days were approx. 1.1 kg. ThroughT. sajor-caju elaborates cellulase and xylanse extracellularly, the activity values were not as high as those of other cellulase producers such asTrichoderma reesei.  相似文献   
25.
A green sonochemical protocol using l-phenylalanine as a water soluble promotor ligand has been developed for the regioselective synthesis of fluorogenic 1,4-disubstituted triazoles (3a-o) via well-known click reaction at 40?°C. l-Phenylalanine is a biocompatible, economical, commercially available and non-toxic ligand which not only serves to stabilize Cu(I) oxidation state but also prevents its disproportion to enhances and modulate the rate of reaction. The designed catalytic system exhibits broad substrate compatibility and can be recycled up to 5 cycles without appreciable loss in the yield of desired product. Gram scale synthesis was successfully accomplished with 92% yield.  相似文献   
26.
27.
A series of functional organosilanes and their esters were synthesized by the hydrosilylation reaction of Si? H group‐bearing organosilicon derivatives with maleic anhydride using Speier's catalyst and their esterification with long‐chain alcohols in the presence of stannous oxide. These products have been characterized using elemental analysis, FT‐IR, 1H, 13C and 29Si NMR. Viscosity, density, pour point, flash point and tribological properties of these compounds have also been evaluated. These esters have a pour point of 相似文献   
28.
The syntheses of the bright deep blue emitting mixed ligand Ir(III) complexes comprising two cyclometalating, one phosphine and one cyano, ligands are reported. In this study, a firm connection between the nature of the excited states and the physicochemical behavior of the complexes with different ligand systems is elucidated by correlating the observed crystal structures, spectroscopic properties, and electrochemical properties with the theoretical results obtained by the density functional theory (DFT) methods. The cyclometalating ligands used here are the anions of 2-(4',6'-difluorophenyl)-pyridine (F2ppy), 2-(4',6'-difluorophenyl)-4-methyl pyridine (F2ppyM), and 4-amino-2-(4',6'-difluorophenyl)-pyridine (DMAF2ppy). The phosphine ligands are PhP(O-(CH2CH2O)3-CH3)2 and Ph2P(O-(CH2CH2O)n-CH3), where Ph = phenyl and n = 1 (P1), 3 (P3), or 8 (P350). The thermal stabilities of the complexes were enhanced upon increasing the "n" value. The crystal structures of the complexes, [(DMAF2ppy)2Ir(P1)CN], (P1)DMA, and [(F2ppyM)2Ir(P3)CN], (P3)F2M, show the cyano and phosphine groups being in a cis configuration to each other and in a trans configuration to the coordinating Cring atoms. The long Ir-Cring bond lengths are ascribed to the trans effect of the strong phosphine and cyano ligands. DFT calculations indicate that the highest occupied molecular orbital (HOMO) is mainly contributed from the d-orbitals of the iridium atom and the pi-orbitals of cyclometalating and cyano ligands, whereas the lowest unoccupied molecular orbital (LUMO) spreads over only one of the cyclometalating ligands, with no contribution from phosphine ligands to both frontier orbitals. Dimethylamino substitution increases the energy of the emitting state that has more metal-to-ligand-charge-transfer (MLCT) character evidenced by the smaller vibronic progressions, smaller difference in the 1MLCT and 3MLCT absorption wavelengths, and higher extinction coefficients (epsilon) than the F2ppy and F2ppyM complexes. However, the increase in the basicity of the dimethylamino group in the DMAF2ppy complexes in the excited states leads to distortions and consequent nonradiative depopulation of the excited states, decreasing their lower photoluminescence (PL) efficiency. The effect of the substituents in the phosphine ligand is more pronounced in the electroluminescence (EL) than in the PL properties. Multilayer organic light emitting devices (OLEDs) are fabricated by doping the Ir(III) complexes in a blend of mCP (m-bis(N-carbazolyl benzene)) and polystyrene, and their device characteristics are studied. The (P3)F2M complex shows a maximum external quantum efficiency (etaex) of 2%, a maximum luminance efficiency (etaL) of 4.13 cd/A at 0.04 mA/cm2, and a maximum brightness of 7200 cd/m2 with a shift of the Commission Internationale de L'Eclairage (CIE) coordinates from (0.14, 0.15) in film PL to (0.19, 0.34) in EL.  相似文献   
29.
A series of novel 2,2′‐(N,N′‐diarylamino)‐4,4′‐diaryl‐5,5′‐arylidene‐bisthiazoles 2 were rapidly and smoothly prepared in good yields by using non conventional techniques i.e. microwave or ultrasonic irradiation, through indium trichloride catalyzed electrophilic substitution reaction of 2‐(N‐arylamino)‐4‐arylthiazoles 1 with various arylaldehydes. All the synthesized compounds were characterized on the basis of their elemental analyses and spectral data (IR, PMR and Mass). The synthesized compounds were also evaluated for their insecticidal activity against Helicoverpa armigera and gave promising results. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:224–231, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20537  相似文献   
30.
Nine empirical force fields used in molecular mechanics calculations are tested for their abilities to reproduce experimental geometric and energy data on cis-syn-cis-perhydroanthracene.  相似文献   
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