bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Simple Spectrophotometric Method for the Determination of Nicotine in Environmental Samples
Authors: Asthana Anupama , Rastogi Rachana , Sunita G. , Gupta V. K. 
Published: May 2015

AbstractA new simple and sensitive spectrophotometric method for the determination of nicotine is described. The method is based on the bromination of nicotine to form dibromonicotine which reacts with potassium iodide to liberate iodine. The iodine liberated then selectively oxidizes leuco crystal violet, and the crystal violet dye formed shows maximum absorbance at 592 nm. Beer's law is obeyed over the concentration range 0.2 μg–2.2 μg of nicotine in a final solution volume of 25 mL (0.008–0.088 ppm). The molar absorptivity of the colour system is 1.40 × 106 1 mol−1 cm−1. The method is free from the interference of other major toxicants. The various analytical parameters were optimized, and the method was applied for the determination of nicotine in cigarette smoke, food, and biological samples.
First Enantioselective Synthesis of the Neolignans Rhaphidecursinol A and Virolongin B
Authors: Ren Xinfeng , She Xuegong , Peng Kun , Su Ying , Xie Xingang , Pan Xinfu , Zhang Hongbin 
Published: May 2015

AbstractThe enantioselective synthesis of the neolignans Rhaphidecursinol A and Virolongin B is reported for the first time. The key reactions in the synthesis were Sharpless asymmetric dihydroxylation and Mitsunobu reaction. The absolute configuration of Rhaphidecursinol A was confirmed.
Effects of Irradiation on the Storage Stability of Red Palm Oil
Authors: Bangash Fazlullah Khan , Ahmad Taufiq , Atta Shaheen , Zeb Alam 
Published: May 2015

AbstractThe samples of Red Palm Oil (RPO) were irradiated with gamma rays using a Cobalt‐60 source (ISSLEDOVATEL, CIS), to dose levels of 1, 5, 10, 15 and 20 KGy and kept for the storage period of 8 weeks along with an untreated control at ambient conditions. The samples were tested for physical characteristics, i.e., Peroxide Value (POV), Iodine Value (IV), Free Fatty Acid value (FFA), Anisidine Value (AV), Color and β‐Carotene. Results revealed that the POV, FFA, and AV were higher in the irradiated samples than the control at the completion of the experimental period. It was also observed that these effects were positively correlated with increasing the irradiation dose. However, a reversed trend was noted in the case of Iodine Value, color and β‐Carotene.
Total Synthesis of Six Natural Products of Benzodioxane Neolignans
Authors: Jing Xiao‐Bi , Wang Li , Han Ying , Shi Yao‐Cheng , Liu Yong‐Hong , Sun Jing 
Published: May 2015

Abstract(±)‐Eusiderin E, (±)‐Eusiderin F, (±)‐Eusiderin K, (±)‐Eusiderin J, (±)‐Eusiderin M and (±)‐Eusiderin G were first synthesized from pyrogallol, in which the Claisen Rearrangement was used to afford two important C6‐ C3 units.
The Mechanism Study of Free Radical SH2′ Reactions by Leaving Group Effect and Secondary α‐Deuterium Kinetic Isotope Effect
Authors: Wu Yuh‐Wern , Huang Shu‐Hui , Tseng Teong‐Fuh , Yang Jyh‐Ferng 
Published: May 2015

AbstractThe reactions of free radical addition to allylic compounds are believed to proceed the SH2′ mechanism. It is not clear whether the SH2′ mechanism is concerted or stepwise. The leaving group effects and the secondary α‐deuterium kinetic isotope effects in free radical SH2′ reactions have been determined. The leaving group effect, kBr/kCl, is from 1.88 to 14.3. The secondary α‐deuterium kinetic isotope effects, kH/kD, are 1.20 for 2‐methylallyl chloride and 1,1‐d2‐2‐methylallyl chloride and 1.22 for allyl chloride and 1,1‐d2‐allyl chloride. The free radical SH2′ reactions seem to favor the concerted mechanism.
Ultrasonic Irradiated Synthesis of N‐(5‐aryl‐2‐furoyl)thiourea Derivatives Containing Substituted Pyrimidine Ring under Phase Transfer Catalysis
Authors: Xue Si‐Jia , Ke Shao‐Yong , Wei Tai‐Bao , Duan Li‐Ping , Guo Yan‐Ling 
Published: May 2015

AbstractA series of N‐(5‐aryl‐2‐furoyl)thiourea derivatives containing substituted pyrimidine ring were synthesized in good yield using PEG‐400 as solid‐liquid phase transfer catalyst under ultrasonic irradiation. The structures of all newly synthesized compounds were elucidated and confirmed by IR, 1H NMR and elemental analysis. Our method has the advantage of shorter reaction time and higher reaction yield compared to the conventional heating method. Preliminary biological tests show that some of the target compounds have better inhibitory activities against roots and stalks of monocotyledon and dicotyledon plants.
A New Synthesis of Angelicin from 7‐Hydroxycoumarin via C‐Propenation‐O‐Vinylation and Ring‐Closing Metathesis
Authors: Tsai Tzu‐Wei , Wang Eng‐Chi 
Published: May 2015

AbstractA new and concise method for the synthesis of angelicin was described. 7‐Hydroxycoumarin was converted into angelicin in good overall yields via the process of c‐propenation‐o‐vinylation and ring‐closing metathesis (RCM).
Chemical Constituents from Clinopodium Urticifolium
Authors: Wei Xiao‐Mei , Cheng Jie‐Kai , Cheng Dong‐Liang , Gao Li‐Ming 
Published: May 2015

AbstractSix new triterpene saponins and a new lignan have been isolated from the n‐BuOH and EtOAc solubles of the MeOH extracts of the whole plant of Clinopodium urticifolium. The structures of the new secondary metabolites, named clinopodiside I‐V (6, 1, 2, 3, 4), clinoposaponin Ga (5) and R‐(Z)‐rosmarinic acid B (7), were deduced from the spectroscopic data (1D, 2D‐NMR, FAB‐MS, HRESI‐MS, EI‐MS) and by chemical transformation studies.
Fluorimetric Determination of Ethionamide in Pharmaceutical Preparations and Biological Fluids
Authors: Walash M. I. , El‐Brashy A. M. , Metwally M. E. S. , Abdelal A. A. 
Published: May 2015

AbstractA highly sensitive and specific fluorimetric method was developed for the determination of ethionamide in pharmaceutical preparations and biological fluids (urine and plasma). The proposed method is based on the study of the quantitative quenching effect of ethionamide on the native fluorescence of eosin in acidic medium due to complex formation. The fluorescence intensity was measured at 536 nm (after excitation at 337 nm). The different experimental parameters affecting the quenching of the native fluorescence of eosin were carefully studied and incorporated into the procedure. Under the described conditions, the method is applicable over the concentration range of 1–8 μg/mL with a detection limit of 80 ng/mL. The percentage recoveries for dosage form, spiked urine and plasma were 99.38 ± 0.824, 99.44 ± 1.58 and 99.25 ± 1.15%, respectively. The results obtained were in good agreement with the official methods. A proposal of the reaction pathway is suggested.
Comment on “Evaluation of Multicenter Electric Multipole Moment Integrals over Integer and Noninteger n‐STOs”
Authors: Guseinov I. I. 
Published: May 2015

AbstractÖzdoǧan (J. Chin. Chem. Soc. 2004, 51, 13) published formulas for evaluating the multicenter electric multipole moment (EMM) integrals over Slater‐type orbitals (STOs). It is demonstrated that all of the formulas presented in this work are not original and they are available in our already published papers or can easily be derived by means of a simple algebra (I. I. Guseinov, J. Mol. Struct. (Theochem) 1996, 367, 83; 1998, 427, 263; Int. J. Quantum Chem. 1998, 68, 145; I. I. Guseinov, B. A. Mamedov, Int. J. Quantum Chem. 2003, 93, 9.
The Copper Clusters in the Particulate Methane Monooxygenase (pMMO) from Methylococcus Capsulatus (Bath)
Authors: Chen Kelvin H.‐C. , Chen Chang‐Li , Tseng Chiu‐Fou , Yu Steve S.‐F. , Ke Shyue‐Chu , Lee Jyh‐Fu , Nguyen Hiephoa T. , Elliott Sean J. , Alben James O. , Chan Sunney I. 
Published: May 2015

AbstractThe particulate methane monooxygenase (pMMO) from Methylococcus capsulatus (Bath) is a multi‐copper protein that hydroxylates methane and other small n‐alkanes to their corresponding alcohols with high regiospecificity and stereoselectivity. The copper ions appear to be arranged into ˜5 trinuclear copper clusters. Two of these clusters are thought to be involved in the dioxygen chemistry and alkane hydroxylation mediated by the enzyme. Accordingly, these catalytic clusters (C‐clusters) are typically oxidized, as the protein is isolated. The remaining copper ions are normally reduced, and it has been suggested that they provide a reservoir of reducing equivalents needed for the turnover of the enzyme. In this study, we have oxidized the protein to different levels of oxidation of the copper ions using dioxygen, hydrogen peroxide, ferricyanide, and dioxygen in the presence of the suicide substrate acetylene, and have characterized the oxidized copper centers using low temperature electron paramagnetic resonance (EPR) and X‐ray absorption spectroscopy. The results are consistent with the grouping of the copper ions into catalytic clusters and electron transfer clusters (E‐clusters). Quantification indicates that there are, indeed, two C‐clusters. A model in which the two C‐clusters are activated by dioxygen starting from their fully reduced states and mediate the hydroxylation chemistry of methane will be presented and discussed.
Mutational Analysis of the Yeast Nucleotide Exchange Factor Mge1p
Authors: Flower Todd R. , Witt Stephan N. 
Published: May 2015

AbstractMge1p is an essential nucleotide exchange factor, expressed by the budding yeast Saccharomyces cerevisiae, that catalyzes the release of ADP from Hsp70 molecules. Without such catalysis the Hsp70 reaction cycle comes to a halt. There is intriguing evidence that Mge1p and its homologues are more than just nucleotide exchange factors; specifically, these proteins may also be molecular thermosensors. In this study, a structure‐function analysis of Mge1p was conducted to ascertain the functional significance of the putative thermosensing domain of Mge1p, which comprises the first ˜66 N‐terminal residues of the protein. We show that (i) yeast cells that express Mge1p 66 exhibit a severe growth defect compared to cells expressing wt Mge1p; and (ii) preliminary results from a genetic screen reveal that mutating Ile102 to Asn in the Mge1p 66 protein partially restores cell growth. To further elucidate the role of the 66 N‐terminal residues, in the future we plan to isolate Mge1p 66 and variants that contain suppressor mutations and conduct biophysical studies that probe the binding of these proteins to mtHsp70.
Configurational Entropy of Proteins: Covariance Matrix versus Cumulative Distribution Calculations
Authors: Sullivan David C. , Lim Carmay 
Published: May 2015

AbstractCalculating the configurational entropy associated with conformational fluctuations constitutes an important challenge in modeling macromolecules. Properly estimating configurational entropy is particularly critical for thoroughly understanding protein folding and assessing contending protein folding mechanisms. Here we use tractable systems where the relative configurational entropy can be calculated analytically to assess two such methods: one based on the atom‐position covariance‐matrix and another based on the cumulative distribution function (CDF) of conformational differences as measured by the root‐mean‐square difference in atomic coordinates. In cases where the conformational distribution of one state is highly dispersed relative to that of another state, the covariance‐matrix greatly overestimates the configurational entropy difference, whereas the CDF reproduces the expected (analytical) difference. As a corollary, the covariance‐matrix discounts the majority of entropy loss associated with imposing excluded‐chain volume constraints in compact polyalanine conformations with chain lengths corresponding to small proteins (50 to 70 amino acids), compared to CDF‐based entropy calculations. The strengths/weakness of the covariance matrix vs. the CDF method for computing relative configurational entropies revealed in this work pave the road to more accurate calculations of the relative configurational entropy of real proteins, in particular upon protein folding.
Support for Nickel as the Labile Metal in the A‐center of the M. Barkeri Acetyl‐CoA Decarbonylase/Synthase Complex
Authors: Arndt Joseph W. , Chen Kelvin H.‐C. , Zhong Xuejun , Krzycki Joseph A. , Chan Michael K. 
Published: May 2015

AbstractThe α8β8γ8δ8ϵ8 acetyl‐CoA decarbonylase synthase (ACDS) complex catalyzes the first step in the conversion of acetate to methane. The critical C‐C bond cleavage of the acetyl group is mediated by the A‐center, aNi‐X‐Fe4S4 cluster that has been localized to the β‐subunit. To elucidate the identity of the labile metal X in the A‐center of purified enzyme, the β‐subunit of the M. barkeri ACDS complex was isolated and studied. Metal analysis revealed the presence of both nickel (1.9) and copper (0.2) per subunit indicating a mixture at the metal site. Treatment of the β‐subunit with the Cu(I) specific chelator, bathocuproine disulfonate (BCS), allowed for the complete removal of the copper in the sample as confirmed by fluorescence quenching of the BCS chelator and subsequent metal analysis. The BCS‐treated β‐subunit was found to have nearly identical activity to the as‐isolated enzyme; importantly, addition of Ni(II) to this BCS‐treated β‐subunit resulted in a 24% increase in acetyltransferase activity over that of the isolated enzyme consistent with activation of the A‐center by incorporation of Ni(II) into sites previously occupied by Cu. These results suggest that while Cu can occupy the labile metal site, it is the Ni‐bound form that is active ‐ providing additional support that the A‐center of the methanogenic ACS consists of aNi‐Ni‐Fe4S4 cluster. Perhaps equally important, these studies demonstrate that BCS/Ni(II) treatment provides a means of curing samples from Cu inactivation ‐ a key step towards obtaining the uniform A‐center needed for detailed structural and mechanistic studies.
Synthesis and Characterization of Organosilicon Substituted Fluorenyl Derivatives
Authors: Khan Shah Alam 
Published: May 2015

AbstractFriedel‐Crafts cycloalkylation of biphenyl with 2,3‐dichlorobutyltrichlorosilane(Cl3Si‐CH2CHClCHClCH3) at a temperature of 100°C in the presence of anhydrous aluminum chloride catalyst gave cyclized product, 9‐methyl‐9‐(2‐trichlorosilylethyl)fluorene 1a, in 33% yield. Methylation of 1a with nucleophilic reagent such as methyl magnesium chloride, gave 9‐methyl‐9‐(2‐trimethylsilylethyl)fluorene 2 while bromination of 2 with excess amount of bromine in DMF resulted in 2,7‐dibromo‐9‐methyl‐9‐(2‐trichlorosilyl)fluorene 3 in good yield. All the compounds were structurally identified by GC/MS, 1H and 13C‐NMR spectroscopy.
Electrocatalysis of the SiC Particle‐Modified Glassy Carbon Electrode for the Oxidation of Adrenaline
Authors: Yu Zhang‐Yu , Kong De‐Sheng , Wu Shu‐Xin , Wang Han‐Qing 
Published: May 2015

AbstractThe electrocatalytic properties of the SiC particle‐modified glassy carbon electrode (MGC) for adrenaline oxidation were studied by cyclic voltammetry (CV), double‐potential step chronocoulometry (DPSCC), and electrochemical impedance spectroscopy (EIS) techniques in McIlvaine buffer solution. It was shown that the electrode modified with SiC particles markedly displayed an electrocatalytic effect on the process of the electrochemical reaction of adrenaline, i.e., the activity and the reversibility of the MGC electrode has been significantly improved. This was attributed to the adsorption effect of the electroactive adrenaline molecules on the MGC electrode surface.
Improvement of Pulse Amperometric Detection Integrated Automated Flow Injection Analysis of Ethylenethiourea Determination
Authors: Lin Meng‐Shan , Wang Jun‐Sheng , Chen Pei‐Yan , Yeh Hsiu‐Hsuan 
Published: May 2015

AbstractImprovement of pulse amperometric detection (PAD) method is demonstrated in determination of ethylenethiourea (imidazolidine‐2‐thione, ETU). The anodic detection of ETU will produce polymeric film on an electrode leading to an inactive electrode surface. Here, the PAD method was used to remove the polymeric film formed on the electrode surface between ETU detection. Further, the scheme was integrated with automated flow injection analysis (AFIA) for determining ETU. The operational parameters of PAD in the AFIA system were discussed thoroughly. The analytical characteristics of the system were evaluated at optimum conditions. The linear range of calibration plot was between 20 to 300 μM (the correlative coefficient, r = 0.999) and the detection limit was 0.9 μM (S/N = 3). The relative standard deviations of detection of 50 μM ETU were 0.82% with and 9.07% without PAD scheme. The results indicate the system is a very promising tool for ETU determination. Finally, the matrix effects of two water samples that were collected from a campus and a farm show good recoveries of 92% and 96%.
Indirect Atomic Absorption Determination of Cocaine via Formation and Liquid‐liquid Extraction of the Iron(III)‐cocaine Complex
Authors: Mohammadzai Imdad Ullah , Hinze Willie L. 
Published: May 2015

AbstractThe principles of metal‐alkaloid ion‐pair formation and liquid‐liquid extraction are applied to the development of a sensitive and convenient atomic absorption spectrophotometery (AAS) method for the indirect determination of cocaine. In an aqueous medium of 5 M hydrochloric acid, cocaine is protonated and is associated with tetrachloro ferrate (III) anion prior to its extraction into 1,2‐dichloroethane. The critical experimental variables were identified and optimized. The method is simple and reproducible with a detection limit (DL) of 0.1 ng cm−3 cocaine in water, a relative standard deviation of 0.07 (n = 12), and the calibration graph was linear up to 50 ng cm−3 cocaine.
Solid‐Phase Synthesis of 2‐Alkenamides from Polystyrene‐Supported α‐Selenocarboxylic Acids
Authors: Liu Xiao‐Ling , Wang Xing‐Cong , Sheng Shou‐Ri 
Published: May 2015

AbstractThe polystyrene‐supported α‐selenoacetic acid and α‐selenopropionic acid were prepared and used for the synthesis of 2‐alkenamides from primary and secondary amines in good yields and high purities.
Comparison of Electrochemical Behavior of Hydroxyl‐substituted and Nonhydroxyl‐substituted Azo Dyes at a Glassy Carbon Electrode
Authors: Yu Jiefei , Jia Jinping , Ma Zifeng 
Published: May 2015

AbstractThe voltammetric behaviour of four azo dyes has been compared at a glassy carbon electrode. It is shown that the azo dyes (e.g. Reactive Brilliant Red x‐3b (RBR x‐3b), Acid Red 6b (AR 6b)) with a hydroxyl group in the ortho position with respect to the azo bridge give rise to well defined, irreversible peaks for the oxidation and reduction process within a pH range of 2–12. In the case of the non‐hydroxyl azo dye (e.g. Reactive Yellow x‐rg (RY x‐rg)), or azo dye with a meta hydroxyl group (e.g. Reactive Orange x‐gn (RO x‐gn)), the oxidation was comparatively tougher, and the peak was not clear or even invisible in the accessible potential range. The mechanism of electrochemical oxidation of RBR x‐3b, as well as AR 6b is proposed. The reduction steps were only accessible when pH < 8 for RY x‐rg and RO x‐gn dye compounds. For the hydroxyl‐substituted dyes, re‐oxidation peaks were obtained in the subsequent scan, owing to the oxidation of reduction products‐amine or hydroazo intermediates.
A New Route to Synthesis of 3,6‐Diaryl‐1,2,4‐triazolo[3,4‐b]1,3,4‐oxadiazoles
Authors: Qiu Zao‐Zao , Dai Chao‐Feng , Chao Shu‐Jun , Xu Peng‐Fei , Zhang Zi‐Yi 
Published: May 2015

AbstractFive new 3,6‐diaryl‐1,2,4‐triazolo[3,4‐b]1,3,4‐oxadiazole derivatives were synthesized by 9 steps from aromatic acids and evaluated for their activities of anticancer and antibacteria. The structures of all new compounds synthesized were elucidated by MS, IR, 1HNMR and HRMS.
Synthesis of Ethyl 2‐Arylaminoimidazo[2,1‐b]benzothiazole‐3‐carboxylates
Authors: Khalafy Jabbar , Ebrahimlo Ali Reza Molla , Dilmaghani Karim Akbari 
Published: May 2015

Abstract3‐Arylamino‐4‐ethoxycarbonylisoxazol‐5(2H)‐ones, substituted on nitrogen with a benzothiazole group, reacts with triethylamine in ethanol under reflux conditions to provide a convenient synthesis of ethyl 2‐aryl‐aminoimidazo[2,1‐b]benzothiazole‐3‐carboxylates.
Kinetic Spectrophotometric Determination of Trace Amounts of Nitrite by Catalytic Reaction between Methylthymol Blue and Bromate
Authors: Pouretedal Hamid Reza , Nazari Behzad 
Published: May 2015

AbstractA kinetic spectrophotometric method for determination of trace nitrite in two dynamic ranges (2–100 and 100–500 ng/mL) based on its catalytic effect on the reaction between methylthymol blue and potassium bromate in acidic (sulfuric acid) media is described. The reaction was monitored spectrophotometrically by measuring the decreasing color of methylthymol blue at 437 nm by the fixed‐time method of 4.0 min at 30°C. The detection limit is 0.6 ng/mL, and the relative standard deviations for 50.0 and 250.0 ng/mL nitrite are 1.6% and 1.3%, respectively. The method was used for the determination of nitrite in water samples.
Mild Oxidation of 1,3,5‐Trisubstituted Pyrazolines with N‐Bromo‐sulphonamides
Authors: Ghorbani‐Vaghei Ramin , Azarifar Davood , Maleki Behrooz 
Published: May 2015

Abstract1,3,5‐Trisubstituted pyrazolines to pyrazoles are carried out efficiently in the presence of new reagents N,N,N′, N′‐tetrabromo‐benzene‐1,3‐disulfonylamine [TBBDA] and N,N′‐dibromo‐N,N′‐1,2‐ethanediylbis‐(p‐toluenesulphonamide) [BNBTS] in solvent‐free conditions with catalytic amounts of SiO2 under microwave irradiation in high yields.
The Structure of Bis[N‐6‐aminopyridyl‐N‐(1S)‐(+)‐10‐camphorsulfonylamino]palladium in the Solid State and in Solution
Authors: Chen Tsun‐Ren , Wu Ying‐Yann , Chen Jhy‐Der , Wang Ju‐Chun 
Published: May 2015

AbstractThe complex, bis[N‐6‐aminopyridyl‐N‐(1S)‐(+)‐10‐camphorsulfonylamino]palladium, Pd[(S)‐APCS]2, 1, was prepared by reaction of 2‐[(1S)‐(+)‐10‐camphorsulfonamino]‐6‐aminopyridine with PdCl2 in THF. Complex 1 has been characterized by spectroscopic methods and its structure has been determined by X‐ray crystallography. Crystal data: space group C2, a= 16.082 (2), b = 17.104 (2), c = 13.051 (2)Å, β = 99.95 (1)°, V = 3535.9 (8) Å3, Z = 2 with final residuals R1 = 0.0491 and wR2 = 0.0944. Two independent molecules, (S,S)‐Pd[(S)‐APCS]2, 1a, and (R,R)‐Pd[(S)‐APCS]2, 1b, were found in each asymmetric unit, which exchange to each other via a series of nitrogen inversion and C‐C bond rotation. The inversion energy (ΔGc1≠) and the energy barrier (δGc2≠) were 11.5 ± 0.1 Kcal mol−1 at 246 K and 9.8 ± 0.1 Kcal mol−1 at 199 K, respectively, calculated by dynamic NMR data.
Ortho‐Alkylation of Phenol with Methanol Using Pb‐Cr Promoted Magnesium Oxide Catalysts
Authors: Ke Jyh‐Harng , Zen Jyh‐Myng , Wang Fey‐Long 
Published: May 2015

AbstractIn this study, Pb‐Cr promoted magnesium oxide catalysts were used to catalyze the ortho‐alkylation of phenol in the presence of excess methanol. The Cr/MgO catalyst exhibited a high conversion of phenol and a relatively high selectivity for the ortho‐alkylation of phenol. The catalytic activity and the stability of Cr/MgO were improved by the addition of a fairly small amount of Pb. The Pb‐Cr/MgO catalyst showed specificity for the ortho‐alkylation of phenol, which was proved by a series of phenol derivative reactions with methanol.
The Synthesis and the X‐Ray Structure of 1,4‐Bis(2‐{4‐[2‐(4‐methylthiophenyl)ethynyl]phenyl}ethynyl)‐2,5‐dihexyloxybenzene
Authors: Xue Cuihua , Luo Fen‐Tair 
Published: May 2015

AbstractThe synthesis and the single crystal structure of the title compound (I), C52H50O2S2, consisting of five benzene rings and four carbon‐carbon triple bonds and with methylthio groups at both ends were described. The distance, according to the X‐ray data, between the two ended sulfur atoms of compound (I) was close to the calculated value from Spartan'04//Hartree‐Fock//3–21G(*). The dihedral angle between the adjacent two benzene rings in this linear conjugated molecule is about 17°.