bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation and Structures of Euphohelins, New Toxic Diterpenes from Euphorbia Helioscopia L.
Authors: Kosemura Seiji , Shizuri Yoshikazu , Yamamura Shosuke 
Published: July 2006

Abstract
Five new toxic diterpenes, euphohelins A, B, C, D, and E, have been isolated from the plant Euphorbia helioscopia L., and their stereostructures have also been elucidated on the basis of their spectral data coupled with some chemical evidence: euphornin, the known toxic diterpene, has been successfully converted into euphohelin A.
Photochemical Ring-expansion Reaction of 1,2-Benzisothiazolinones
Authors: Kamigata Nobumasa , Hashimoto Satoshi , Kobayashi Michio , Nakanishi Hiroshi 
Published: July 2006

Abstract
The photochemical reaction of a series of 2-aryl-1,2-benzisothiazol-3(2H)-ones (1) under deaerated conditions was found to give dibenzo[b,f][1,4]thiazepin-11(10H)-ones (2). A mechanism through a biradical species is proposed for the photoreaction. When the photolysis of 1 was carried out in the presence of oxygen, 2-aryl-1,2-benzisothiazol-3(2H)-one 1-oxides (11) were formed together with compounds 2.
Interaction of Galvinoxyl Radical with Ascorbic Acid, Cysteine, and Glutathione in Homogeneous Solution and in Aqueous Dispersions
Authors: Tsuchiya Jyunichi , Yamada Teruaki , Niki Etsuo , Kamiya Yoshio 
Published: July 2006

Abstract
The rates of interaction of galvinoxyl radical with ascorbic acid, cysteine, and glutathione have been studied in homogeneous solution and in water dispersions as a model reaction of vitamin E radical with these reducing agents in biological systems. The rate was measured by following the disappearance of galvinoxyl radical with absorption spectroscopy and electron spin resonance. In every system, galvinoxyl reacted with these reducing substrates and their relative reactivities decreased in the order of ascorbic acid&gt;cysteine&gt;glutathione. For any reducing substrate, the rate was fastest in homogeneous solution and slowest in micelle in Triton X-100 aqueous solution, and the rate in liposome system was in between.
Reactivities of Stable Rotamers. XVI. Tributylstannane Reduction and Electron-impact Mass Spectra of Rotamers of 1,2,3,4-Tetrachloro-9-(2-chloro-1,1-dimethylethyl)triptycene and 1,2,3,4-Tetrachloro-9-(2-chloro-1-chloro-methyl-1-methylethyl)triptycene
Authors: Yonemoto Katsumi , Kakizaki Fumihiko , Yamamoto Gaku , Nakamura Nobuo , Oki Michinori 
Published: July 2006

Abstract
1,2,3,4-Tetrachloro-9-(2-chloro-1-chloromethyl-1-methylethyl)triptycene (1) and 1,2,3,4-tetrachloro-9-(2-chloro-1,1-dimethylethyl)triptycene (2) were reduced with tributylstannane in the presence of azobisisobutyronitrile in benzene. 1 was reduced to 2 which was further converted to a 9-t-butyltriptycene under the conditions. The chloromethyl group sc to the peri-chloro substituent was found to be ca. 7 times more reactive than the ap in sc-1. sc-2, was consumed 1.7 times more rapidly than ap-2. The results are attributed to the participation of the peri-chloro substituent in the chlorine abstraction. Electron impact mass spectra of these compounds reveal that they give different intensities at a number of peaks. The difference is again attributed to the chloro participation in stabilizing the cation formed.
Preparation of Pyrido- and Azepino-fused Cycl[3.2.2]azines
Authors: Noguchi Michihiko , Tanigawa Noriyuki , Kajigaeshi Shoji 
Published: July 2006

Abstract
Pyrido- and azepino-fused cycl[3.2.2]azines were obtained by the reaction of the corresponding pyrido- and azepino[hi]indolizines with electron-deficient acetylenes in the presence of appropriate oxidants. The reaction pathway of their preparation was proposed to be a sequence of Michael addition of indolizine to acetylene, 10π-electrocyclic reaction of Michael adduct, and dehydrogenation by means of the chemical conversions of the isolated intermediates.
Kinetic Study of the Thermal Decomposition of Isocyanic Acid in Shock Waves
Authors: Kajimoto Okitsugu , Kondo Osamu , Okada Kazuo , Fujikane Jiro , Fueno Takayuki 
Published: July 2006

Abstract
Thermal decomposition of isocyanic acid HNCO diluted to less than 2.0 mol% in argon was studied behind incident shock waves over the temperature range 2100–2500 K. The decomposition course was followed by monitoring the light absorption of HNCO and NH(3Σ−) at 206 and 336 nm, respectively. It is confirmed that the primary step of the decomposition is a bimolecular process HNCO+Ar→NH(3Σ−)+CO+Ar, ΔH°0=337 kJ mol−1, with the low-pressure limit rate constants k=1017.23±0.36exp[−(402±17) kJ mol−1/RT] cm3 mol−1 s−1. The siglet-to-triplet crossing point is estimated on the basis of the RRKM low-pressure-limit rate constant calculations. The overall decomposition mechanism is suggested and its validity is confirmed by computer simulation of the time–concentration profiles of NH(3Σ−) at varying temperature.
The Synthesis and Thermal Behavior of Barium Bis(hydrogenphosphoramidate) and Barium Phosphoramidate
Authors: Sato Shoji , Watanabe Makoto 
Published: July 2006

Abstract
Barium bis(hydrogenphosphoramidate) monohydrate and barium phosphoramidate monohydrate were made by mixing a solution of potassium hydrogenphosphoramidate and a solution of barium chloride at pH 6.1–6.4 and 10.0–10.5 respectively. Both products were stable at room temperature. Barium bis(hydrogenphosphoramidate) monohydrate was decomposed by water to produce the orthophosphate. This was condensed to make polyphosphates above 100 °C and finally formed barium metaphosphate above 500 °C. The thermal products of the hydrogenphosphoramidate did not produce any phosphate with imino groups. Barium phosphoramidate produced ortho-, di-, imidodi-, and triphosphates when it was heated above 200 °C. These thermal products were converted to dibarium diphosphate in air above 500 °C.
Solvent Effect on Adsorption of TCNQ onto Metal Oxides
Authors: Esumi Kunio , Miyata Kazuaki , Meguro Kenjiro 
Published: July 2006

Abstract
7,7,8,8-Tetracyanoquinodimethan(TCNQ) was adsorbed on the surfaces of alumina and titania from three basic solvents. The amount of TCNQ adsorbed decreased with an increase in the acid-base interaction between TCNQ and the basic solvent for both metal oxides. The TCNQ anion radicals were formed as a result of electron transfer from the metal oxide surfaces to adsorbed TCNQ. Further, the concentration of TCNQ anion radicals formed on the oxides after the TCNQ adsorption decreased also with an increase in the acid-base interaction between TCNQ and the basic solvent.
Preparation and Properties of Oligocytidylates with 2′–5′ Internucleotide Linkage
Authors: Sawai Hiroaki , Ohno Masaji 
Published: July 2006

Abstract
Oligocytidylates upto a pentamer were prepared by lead(II) ion catalyzed polymerization of cytidine 5′-phosphorimidazolide in aqueous solution. 2′–5′ internucleotide linkage was preferentially formed. The yields of the 2′–5′ linked dimer, trimer, tetramer and pentamer were 17.0, 5.5, 1.9, and 0.7%, respectively. Some of their properties were studied by NMR, CD, UV, and chromatography and compared with the corresponding 3′–5′ linked oligomers which were prepared enzymatically.
Potential Energies of Rotation of Double Bond in Ethylene Molecule and Ion
Authors: Ichikawa Hiroshi , Ebisawa Yukiko , Shigihara Atsushi 
Published: July 2006

Abstract
MP3/6-31G** calculations show that the potential barrier of a double-bond rotation in an ethylene ion is 137 kJ mol−1 (about half that of the molecular state) and that the orthogonally twisted ion has a C2v symmetry. The geometries are discussed in relation to the total energies.
Strong Embedding Effect of Decalin Walls on Cation Complexation in Crown Ethers
Authors: Kobiro Kazuya , Takahashi Mitsuru , Takada Shigeki , Odaira Yoshinobu , Kawasaki Yoshikane 
Published: July 2006

Abstract
Cylindrical crown ether, tridecalino-18-crown-6, shows strong embedding effect toward coordinated thallium ion.
Reaction of Leucomalachite Green with Chloranil
Authors: Nishimura Norio , Motoyama Takushi 
Published: July 2006

Abstract
The reaction of Leucomalachite Green with chloranil to produce Malachite Green cations has been carried out in acetonitrile. Prior to the formation of the cations, a 1:1 CT complex is formed between the reactants. The equilibrium and the rate constants were estimated.
A Kinetic Study of Thermal Rotational Isomerization of 5,10,15,20-Tetrakis(o-aminophenyl)porphyrin and 5,10,15,20-Tetrakis(o-pivaloylaminophenyl)porphyrin
Authors: Hatano Keiichiro , Anzai Kazunori , Nishino Akemi , Fujii Keiko 
Published: July 2006

Abstract
Rates of thermal interconversion of atropisomers of 5,10,15,20-tetrakis(o-aminophenyl)porphyrin and 5,10,15,20-tetrakis(o-pivaloylaminophenyl)porphyrin have been determined.
Palladium-catalyzed Reaction of Stannyl Sulfide with Aryl Bromide. Preparation of Aryl Sulfide
Authors: Kosugi Masanori , Ogata Toshimi , Terada Masahiro , Sano Hiroshi , Migita Toshihiko 
Published: July 2006

Abstract
Tributylstannyl alkyl or aryl sulfide and bis(tributylstannyl) sulfide were found to be useful to prepare aryl sulfides in good yields under the usual conditions of the palladium-catalyzed reaction with aryl bromides.
Ternary Coordination Complexes Formed by Copper(II) with Thio-or Dithiodialkanoic Acids and Some Selected Ethyl-substituted Malonic Acids
Authors: Shelke D N 
Published: July 2006

Abstract
Binary and ternary complexes formed by copper(II) with thio- or dithiodialkanoic acids and ethyl-substituted malonic acids have been investigated potentiometrically in an aqueous solution and the relevant stability constants have been evaluated using computer technique. Thio- and dithiodialkanoic acids were thiodiacetic, dithiodiacetic, 3,3′-thiodipropionic, and 3,3′-dithiodipropionic acids. The results are discussed in terms of substituent influences upon the chelation of the malonate dianions to the systems copper(II)-thiodialkanoic acids. It is suggested that in the mixed copper chelates containing thiodiacetic acid, the geometrical characteristics of the more basic ligand, governs the coordination of the other ligand.
Phase Relations in the System NH4Ti2P3O12–NH4Zr2P3O12
Authors: Ono Akira 
Published: July 2006

Abstract
Crystalline phases in the system NH4Ti2P3O12–NH4Zr2P3O12 were prepared in a high pressure vessel, and were investigated by X-ray method. New compounds, (NH4)1+xTi3+x(Ti4+,Zr)2−xP3O12 (1≥x), with the langbeinite-type structure were produced under reducing conditions.
Synthesis of 2,6,8-Trinitro-4H-cyclopenta[def]phenanthren-4-one as an Electron Acceptor
Authors: Minabe Masahiro , Yoshida Masaaki , Kimura Okitoshi 
Published: July 2006

Abstract
2,6,8-Trinitro-4H-cyclopenta[def]phenanthren-4-one (TNC) was synthesized by the nitration of the parent ketone. TNC formed charge-transfer complexes with polycyclic aromatic hydrocarbons (PAH). The property of TNC as an electron acceptor was compared with that of 2,4,7-trinitro-9H-fluoren-9-one (TNF). TNC was found to be a better complexing agent than TNF.
119Sn NMR Spectroscopic Determination of Diastereomeric Ratio of Some Optically Active Organotin Compounds
Authors: Otera Junzo , Yano Toru 
Published: July 2006

Abstract
Diastereomeric ratio of optically active organotin compounds, R2*SnX2 and R1R2R3SnR*, was successfully determined by means of 119Sn NMR spectra.
The Facile Synthesis of Unsymmetrical Ketones Using Acetone Dimethylhydrazone
Authors: Yamashita Masakazu , Matsumiya Kaoru , Tanabe Minako , Suemitsu Rikisaku 
Published: July 2006

Abstract
Unsymmetrical ketones were prepared by successive alkylation of acetone dimethylhydrazone. Application of this reaction to the synthesis of dihydrojasmone is described.
Solvent Effects on Chemical Reactivities of Conjugated Molecules
Authors: Ohmae Takayuki 
Published: July 2006

Abstract
The propagator method is applied to the study of solvent effects on chemical reactivities of conjugated molecules. It is shoen that the number of π-electrons of a solute molecule (a conjugated molecule) controls the solvent effects on chemical reactivities. The obtained theory is applied to the study of solvent effects on selectivities of pericyclic reactions.
Charge-transfer Complexes, Gas-liquid Chromatographic and Photochemical Characteristics, and Solvent Adducts of Polyphenylenes and Related Linear Polyphenylsls
Authors: Fujioka Yasuhiro 
Published: July 2006

Abstract
The absorption spectra of the charge-transfer (CT) complexes formed by two acceptors (tetracyanoethylene and 2,3-dichloro-5,6-dicyano-p-benzoquinone) with thirteen macrocyclic polyphenylenes and with thirty-eight linear polyphenyls were measured in dichloromethane. A linear relationship existing between the first transitions of the CT-complexes and those of the uncomplexed donor hydrocarbons made it possible to predict the CT-bands of new polyphenylenes and polyphenyls. By the gas-liquid chromatography using a glass capillary column, forty-nine polyphenyls and polyphenylenes, containing a large number of isomers, were successfully analyzed. The relationship between the retention times and the structure of linear polyphenyls was expressed by means of a simple empirical equation, and the equation was also applicable to the polyphenylenes by adding a correction factor. These equations are extremely useful for the estimation of the retention time and elution order and the structure of unknown polyphenyls and polyphenylenes. The reductive irradiation of m,m,o,p,o-pentaphenylene provided the bridged annulene compound. For six polyphenylenes and the related compounds, the criteria for the occurrence of the intramolecular photocoupling reaction were discussed. Among the examined polyphenylenes, m,o,o,m,o,o-hexaphenylene and o,p,p,o,p,p,o,p,p-nonaphenylene formed the adducts with several solvents.
Molecular Design of Crown Ethers. 3. Extraction of Alkaline Earth and Heavy Metal Picrates with 14- to 17-Crown-5 and 17- to 22-Crown-6
Authors: Inoue Yoshihisa , Ouchi Mikio , Hakushi Tadao 
Published: July 2006

Abstract
The solvent extraction of alkaline earth and heavy metal picrates with a series of ring-contracted and ring-enlarged crown ethers has been carried out in order to reveal the effects of methylene-chain length upon cation-binding ability. Compared with the parent 3m-crown-m, the ring-contracted crown ethers and their sila analogues possess limited extractabilities, often as low as those for the corresponding glymes. On the other hand, the ring-enlarged crown ethers, in general, show gradual, but not drastic, decreases in extractability for most cations with increasing methylene-chain length. Interestingly, the extractabilities for Ag+, Tl+, and Ba2+ do not decrease monotonously with ring expansion; in particular 16-crown-5 is a better extractant for Ag+ than 15-crown-5 and even than 18-crown-6. These results are accounted for in terms of cavity size, conformation, and molecular symmetry of crown ethers. Effects of cation hydration upon extractability and the limitations of solvent extraction technique are also discussed.
Synthesis and Properties of Gramicidin S Analogs Containing d-Phe–l-Pro–d-Val or l-Phe–l-Pro–d-Val Sequences in Place of d-Phe–l-Pro–l-Val Sequence in the β-Turn Part of the Antibiotic
Authors: Tamaki Makoto , Okitsu Tadashige , Araki Mie , Sakamoto Honami , Takimoto Michiaki , Muramatsu Ichiro 
Published: July 2006

Abstract
In order to investigate the contribution of configurations of amino acid residues around Pro residues in gramicidin S to its activity and conformation, [d-Val1,1′]- and [d-Val1,1′ l-Phe4,4′]-gramicidin S were synthesized by a liquid-phase method. The CD spectra of these analogs and gramicidin S in aqueous solutions differ from each other, indicating that these peptides have different conformations. These analogs have practically no activity against the Gram-positive microorganisms tested, indicating the importance of the presence of the d-Phe–Pro–Val sequence in gramicidin S regarding activity.
The Spin Exchange of Nitroxide Radicals with Ni2+ Ions in SDS Micellar Solutions
Authors: Aizawa Masayuki 
Published: July 2006

Abstract
The spin-exchange rate of three kinds of hydrophobic nitroxide radicals with paramagnetic ions, Ni2+ ions, was measured in an aqueous sodium dodecyl sulfate (SDS) micellar solution at 30 °C. In the presence of SDS micelles, two of the three radicals had their spin-exchange rates accelerated, whereas the rate of the other radical was deaccelerated. These strange results were interpreted on the basis of a different solubilized location of the radicals in SDS micelles. The translational mobility of the Ni2+ ions on a micellar surface was estimated from the spin-exchange rate in the accelerated systems.
Theory of Time-resolved Resonance Raman Scattering from Vibrationally Hot Molecules
Authors: Fujimura Yuichi , Ohtsuki Yukiyoshi , Nakajima Takeshi 
Published: July 2006

Abstract
A theory of time-resolved resonance Raman scattering (RRS) from molecules is developed. The time-resolved RRS cross section is defined as a product of the time-dependent vibronic energy distribution and the scattering cross section from the single vibronic level. The theory is applied to the time-resolved RRS from vibrationally hot molecules whose vibronic distribution characterized by a canonical distribution with temperature higher than that of the heat bath relaxes to the equilibrium one in the presence of a collisional vibrational relaxation. Analytical expressions for the time-resolved RRS cross section are derived within a displaced harmonic oscillator model. It is shown that in the strong coupling case the intensities of the Stokes and anti-Stokes Raman bands in the rigorous resonance case vary inversely as the time-dependent average vibrational occupation number. Some model calculations are performed to illustrate the time-dependent intensity changes of the Raman bands.
Delayed Fluorescence of Zinc Porphyrin in Poly(vinyl alcohol) Film
Authors: Ohno Osamu , Kaizu Youkoh , Kobayashi Hiroshi 
Published: July 2006

Abstract
The delayed fluorescence was observed at room temperature with tetrakis(4-sulfophenyl)porphinatozinc (ZnTPPS4) dyed on poly(vinyl alcohol) (PVA) film. In the film, the T-T annihilation is prohibited since any two molecules in the excited triplet can not encounter during their lifetime. Three types of luminescence emission were observed; fluorescence (S1→S0), phosphorescence (T1→S0) and delayed fluorescence (T1\ightsquigarrowS1→S0). The delayed fluorescence can be detected only at elevated temperatures where thermal activation from the lowest excited triplet can repopulate the lowest excited singlet.
Crystal Structure of Nonstoichiometric Tetranuclear Platinum Compound, cis-Diammineplatinum α-Pyrrolidone Violet, [Pt4(NH3)8(C4H6NO)4](PF6)2(NO3)2.56·5H2O
Authors: Matsumoto Kazuko 
Published: July 2006

Abstract
Nonstoichiometric platinum tetranuclear compound, cis-Diammineplatinum α-Pyrrolidone Violet, [Pt4(NH3)8(C4H6NO)4)(PF6)2(NO3)2.56·5H2O, has been synthesized and the crystal structure has been solved with X-ray diffraction analysis. The crystal is triclinic with the space group of P\bar1 and cell dimensions of a=13.530(8), b=19.242(9), c=10.222(3) Å, α=96.56(9), β=93.82(9), γ=74.64(8)°, V=2547.4 Å3, and Z=2. The structure have been solved by heavy atom method and the final discrepancy index R1 was 0.094 and R2 was 0.090. The cation is structurally identical with those of cis-Diammineplatinum α-Pyridone Yellow(PPY), [Pt4(NH3)8(C5H4NO)4]4+, cis-Diammineplatinum α-Pyridone Blue(PPB), [Pt4(NH3)8((C5H4NO)4]5+, and cis-Diammineplatinum α-Pyrrolidone Tan(PPT), [Pt4(NH3)8(C4H6NO)4]6+, and consists of four platinum atoms linked in a chain with bridging pyrrolidone ligands. Each platinum atom is cis coordinated by two ammine ligands and either two exocyclic oxygen atoms or two deprotonated ring nitrogen atoms of α-pyrrolidone ligands. The Pt-Pt bond distances are 2.848(2), 2.875(2), 2.839(2), and 2.875(2) Å, which are intermediate between those of PPY and PPB, indicating that the average platinum oxidation state is between 2.0 and 2.25. According to the potentiometric: oxidative titration of the compound using Ce(IV), the average platinum oxidation state is 2.14 and therefore the compound is considered to consist of 44% of [Pt4(NH3)8(C4H6NO)4]4+ and 56% of [Pt4(NH3)8(C4H6NO)4]5+.
Synthesis of 6-Alkylpurine Derivatives by Nickel-complex-catalyzed Coupling Reaction of 6-(Methylthio)purine Derivatives with Grignard Reagents
Authors: Sugimura Hideyuki , Takei Hisashi 
Published: July 2006

Abstract
6-(Methylthio)purine reacted with RMgX (R=C6H5, CH3(CH2)nCH2 (n=2 to 6), C6H5CH2CH2, (CH3)2 C=CHCH2CH2) in the presence of 5 mol% [NiCl2(Ph2PCH2CH2CH2PPh2)] in refluxing THF for 8 h to afford 6-aryl or 6-alkylpurines in 62–74% yields. By applying this reaction to 6-(methylthio)purine nucleoside, 6-(4-methyl-3-pentenyl)-9-β-d-ribofuranosylpurine was synthesized.
Preparation, Properties, and Analytical Applications of Crystalline Tin(IV) Tungstoselenate
Authors: Nabi Syed Ashfaq , Siddiqi Zia Mahmood 
Published: July 2006

Abstract
Synthesis of tin(IV) tungstoselenate has been done under a variety of conditions. The effects of mixing ratio of reagents and the pH of the mixture on the properties of the material have been studied. The crystalline sample of tin(IV) tungstoselenate has been chosen for detailed studies, such as chemical and thermal stabilities, chemical composition, pH-titrations, IR and X-ray analyses. On the basis of above studies a tentative formula has been proposed for tin(IV) tungstoselenate. The adsorption behaviour of metal ions in different concentrations of perchloric acid has been studied. On the basis of Kd values few analytically important separations of metal ions have been achieved on small columns of tin(IV) tungstoselenate.
The Unusually Strong Effect of a 4-Cyano Group upon Electronic Spectra and Dissociation Constants of 3-Substituted 7-Hydroxycoumarin
Authors: Wolfbeis Otto S , Koller Ernst , Hoghmuth Petra 
Published: July 2006

Abstract
Synthesis, absorption and fluorescence spectra as well as pKa values of 7-hydroxycoumarins with electron-withdrawing substituents in positions 3 are described. Introduction of a 4-cyano group is achieved by oxidative cyanation of coumarins using potassium cyanide and elemental bromine. 7-Hydroxycoumarins without a 4-cyano group are useful indicators for measuring physiological pH values due to their intense fluorescences, longwave absorptions and emissions, as well as pKa values of around 7. The presence of a 4-cyano group gives rise to a dramatic longwave shift in absorption (30–40 nm in methanol) and emission (55–80 nm). In water solution, the fluorescence maxima are at around 570–600 nm, with excitation maxima between 410 and 510 nm, depending on whether the phenol or phenolate species is excited. For all coumarins under investigation, fluorescence is from the anion form even in the pH 2–7 range. This phenomenon is interpreted in terms of excited state dissociation according to the Forster model. The interpretation is corroborated by calculations of the excited state pKa values, which show them to be lower by 4.5–6.4 units than those of the ground state.
Aromatic Systems with 10π Electrons Derived from 3a-Azapentalene. Part 40. Studies on the 1,2,4-Triazolo[4,3-b][1,2,4]triazole Series
Authors: Alajarin Mateo , Molina Pedro , Tarraga Alberto , Vilaplana M Jesús , Foces-Foces M de la Concepción , Hernandez Cano Felix , Claramunt Rosa M , Elguero Jose 
Published: July 2006

Abstract
The synthesis, structure, and reactivity of several 1,2,4-triazolo[4,3-b][1,2,4]triazole derivatives have been studied. Structures have been established throughout a careful carbon-13 NMR study, and for the most unusual one (inner salt of 2-methyl-3-methylthio-6-phenyl-7H-1,2,4-triazolo[4,3-b][1,2,4]triazolium hydroxide) by X-ray crystallography: the space group is P21/c, the cell constants are a=12.6939(5), b=16.0936(6), c=12.0239(5) and β=107.247(3)° and Z=8. The S-methyl group is directed towards the fusion of the five-membered rings at +/−syn conformations. The azapentalene moieties have the first atoms of the substituents on its plane and the 6-phenyl rings make an angle of −26.7 and −4.3° with it, in the two independent molecules respectively.