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961.
Krishnan Ravikumar Balasubramanian Sridhar Jagadeesh Babu Nanubolu Govindaraju Karthik Basi Venkata Subba Reddy 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(11):1001-1009
Spiro scaffolds are being increasingly utilized in drug discovery due to their inherent three‐dimensionality and structural variations, resulting in new synthetic routes to introduce spiro building blocks into more pharmaceutically active molecules. Multicomponent cascade reactions, involving the in situ generation of carbonyl ylides from α‐diazocarbonyl compounds and aldehydes, and 1,3‐dipolar cycloadditon with 3‐arylideneoxindoles gave a novel class of dispirooxindole derivatives, namely 1,1′′‐dibenzyl‐5′‐(4‐chlorophenyl)‐4′‐phenyl‐4′,5′‐dihydrodispiro[indoline‐3,2′‐furan‐3′,3′′‐indoline]‐2,2′′‐dione, C44H33ClN2O3, (I), 1′′‐acetyl‐1‐benzyl‐5′‐(4‐chlorophenyl)‐4′‐phenyl‐4′,5′‐dihydrodispiro[indoline‐3,2′‐furan‐3′,3′′‐indoline]‐2,2′′‐dione, C39H29ClN2O4, (II), 1′′‐acetyl‐1‐benzyl‐4′,5′‐diphenyl‐4′,5′‐dihydrodispiro[indoline‐3,2′‐furan‐3′,3′′‐indoline]‐2,2′′‐dione, C39H30N2O4, (III), and 1′′‐acetyl‐1‐benzyl‐4′,5′‐diphenyl‐4′,5′‐dihydrodispiro[indoline‐3,2′‐furan‐3′,3′′‐indoline]‐2,2′′‐dione acetonitrile hemisolvate, C39H30N2O4·0.5C2H3N, (IV). All four compounds exist as racemic mixtures of the SSSR and RRRS stereoisomers. In these structures, the two H atoms of the dihydrofuran ring and the two substituted oxindole rings are in a trans orientation, facilitating intramolecular C—H...O and π–π interactions. These weak interactions play a prominent role in the structural stability and aid the highly regio‐ and diastereoselective synthesis. In each of the four structures, the molecular assembly in the crystal is also governed by weak noncovalent interactions. Compound (IV) is the solvated analogue of (III) and the two compounds show similar structural features. 相似文献
962.
P. Haranath M. F. Stephen Babu U. Anasuyamma C. Naga Raju C. Suresh Reddy 《Heteroatom Chemistry》2005,16(7):572-575
Novel 3 substituted 1,5‐dihydro‐2,4,3‐benzodioxaphosphepine 3‐oxides ( 5a–h ) were synthesized by reacting 1,2‐benzenedimethanol ( 1 ) with phosphorus tribromide in the presence of triethylamine at 0–30°C and subsequent reaction of the monobromide ( 2 ) with different Grignard reagents ( 3 ) at room temperature. The products ( 4 ) were converted to corresponding oxides 5a–i by oxidation with H2O2 at room temperature. The chemical structures of all the products were confirmed by analytical, IR and NMR (1H, 13C, and 31P) spectral data. Their antifungal and antibacterial activity is also evaluated. Most of these compounds exhibited moderate antimicrobial activity in the assay. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:572–575, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20154 相似文献
963.
A distributed feedback dye laser based on second order Bragg scattering due to a sinusoidal susceptibility modulation is reported.
Rhodamine 6G dye solution in three different solvents; methanol, ethanol and benzyl alcohol is pumped by interference fringes
produced by two beams from the second harmonic of Nd:YAG laser. Output power is plotted as a function of the pump power. The
spectrum of dye laser shows a new type of modulation. 相似文献
964.
A host-guest optical sensor for the determination of aliphatic amines as exemplified by octylamine is proposed. It is based
on the reversible fluorescence enhancement of heptakis(2,6-di-O-isobutyl)-β-cyclodextrin(DOB-β-CD) hosting tetraphenylporphyrin
(TPP) immobilized in poly(vinyl chloride) (PVC) membrane by aliphatic amine extracted from aqueous phase into membrane phase.
The optimum membrane contained 1.15 wt % TPP, 6.15 wt % DOB-β-CD as sensing reagent and other membrane materials. The fluorescence
enhancement of the membrane resulted from the formation of a stable three-component complex among DOB-β-CD, TPP, and aliphatic
amines. With the optimum conditions described, the fluorescence response of the sensor to octylamine shows a good correlation
with the theoretically derived equation in the range 1.0 × 10–6 to 8.0 × 10–4 mol/L. The response characteristics including reversibility, response time, reproducibility and lifetime and selectivity
of this optical device are also discussed in detail. This sensor has also been applied for the determination of octylamine
in water samples containing interferents with satisfactory recovery.
Received: 21 November 1999 / Revised: 10 January 2000 / Accepted: 15 January 2000 相似文献
965.
M.萨哈伊 朱胜江 甘翠云 朱凌燕 杨利明 许瑞清 全明吉 姜卓 张征 J.H.Hamilton A.V.Ramayya B.R.S.Babu J.K.Hwang W.C.Ma J.Komicki J.D.Cole R.Aryaeinejad M.W.Dirgert J.O.Rasmussen M.A 《中国物理 C》2000,24(11):1018-1023
通过对252Cf自发裂变产生的瞬发γ谱的测量,对丰中子奇A核145,147Ce的高自旋态进行了研究,首次识别了145Ce的集体带结构,扩展了147Ce的集体带结构,扩展了147Ce的能级,并新识别了3个边带,粒子–转子模型的计算指出,145,147Ce的晕带可能来自于νi13/2轨道的耦合,145Ce基态起源于(νh9/2νf7/2)组态混合,而147Ce基态则起源于νh9/2轨道.在这两个核中未观测到明显的八极形变带,然而,在147Ce中观测到的一个边带,可能显露出八极关联的迹象. 相似文献
966.
The wide use of manganese dioxide(MnO2)as an electrode in all-solid-state asymmetric supercapacitors(ASCs)remains challenging because of its low electrical conductivity.This complication can be circumvented by introducing trivalent gadolinium(Gd)ions into the MnO2.Herein,we describe the successful hydrothermal synthesis of crystalline Gd-doped MnO2 nanorods with Ni(OH)2 nanosheets as cathode,which we combined with Fe3O4/GO nanospheres as anode for all-solid-state ASCs.Electrochemical tests dem on strate that Gd dopi ng sign ifica ntly affected the electrochemical activities of the MnO2,which was further enhanced by introducing Ni(OH)2.The GdMnO2/Ni(OH)2 electrode offers sufficient surface electrochemical activity and exhibits excellent specific capacity of 121.8 mA h g-1,at 1A g-1,appealing rate performance,and ultralong lifetime stability(99.3%retention after 10,000 discharge tests).Furthermore,the GdMnO2/Ni(OH)2//PVA/KOH//Fe3O4/GO solid-state ASC device offers an impressive specific energy density(60.25 W h kg-1)at a high power density(2332 W kg-1).This investigation thus shows its large potential in developing novel approaches to energy storage devices. 相似文献
967.
968.
A concise synthesis of α‐benzylidene‐γ‐methyl‐γ‐butyrolactones 5a – g from substituted benzaldehydes is described. Compounds 1a – g on reaction with phosphorane 2 , provide the pentenoates 3a – g , which can be hydrolyzed to the acids 4a – g . The latter are cyclized to the corresponding butyrolactones 5a – g in excellent yields. The pentenoates 3a – g , on acid catalyzed cyclization, also provide 5a – g in very high yields. 相似文献
969.
970.