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21.
22.
R. Krishna D. Velmurugan M. Shanmugasundaram R. Raghunathan K. Sekar S. Shanmuga Sundara Raj H.‐K. Fun 《Crystal Research and Technology》2002,37(1):135-141
The crystal structure of the title compound “1′,2′,3′,4′‐tetrahydro‐1,3‐diphenyl‐4‐chlorospiro[2‐pyrazoline‐5,2‐napthalen] 1′one” has been determined. The structure consists of a pyrazoline ring, three aromatic rings and a tetralone moiety. All the aromatic rings are planar while the cyclohexonone ring of the tetralone moiety is in the distorted sofa conformation. The molecular packing is stabilized by C‐H…O and C‐H…π type inter molecular interactions. 相似文献
23.
L. Govindasamy D. Velmurugan V. Raghukumar Il‐Hawn Suh V. T. Ramakrishnan 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):80-81
In the title compound, C29H30N6, the naphthyridine ring is almost planar with a dihedral angle of 5.4 (1)° between the pyridyl rings. The dihedral angles between the naphthyridine system and the diethylaminophenyl, phenyl and pyrrolidine rings are 53.1 (1), 19.8 (1) and 20.9 (1)°, respectively. The pyrrolidine ring adopts a half‐chair conformation. The molecule is stabilized by weak C—H?N interactions. 相似文献
24.
Hoong‐Kun Fun R. Sankaranarayanan D. Velmurugan S. Shanmuga Sundara Raj G. Babu P. T. Perumal 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(4):475-476
In the title compound, C26H22N2O2S, the tetrahydropyridine ring has a conformation intermediate between half‐chair and sofa. The tetrahydroquinoline mean plane makes a dihedral angle of 73.3 (1)° with the cyclopentene ring, which adopts an envelope conformation, and an angle of 45.45 (4)° with the indole best plane. The dihedral angle between the benzene and pyrrole rings is 2.6 (1)°. The orientations of the phenyl ring on the sulfonyl group and of the indole are governed by weak C—H?O interactions. The packing of the molecule in the solid state is stabilized by C—H?O and C—H?N hydrogen bonds. 相似文献
25.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun V. Raghukumar V. T. Ramakrishnan 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):723-725
In the title compounds, C17H15N3 and C20H22N4, the methyl derivative crystallizes with two molecules in the asymmetric unit, while the N,N‐diethylamino derivative crystallizes with one molecule per asymmetric unit. The biphenyl twist angle for both molecular structures is approximately 45°. The molecular packing is stabilized by N—H?N hydrogen bonds. 相似文献
26.
A. Subbiah Pandi D. Velmurugan S. Shanmuga Sundara Raj Hoong‐Kun Fun P. R. Seshadri D. Thirumalai 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):821-824
10‐(4‐Fluorophenyl)‐3,3,6,6,9‐pentamethyl‐3,4,6,7,9,10‐hexahydroacridine‐1,8(2H,5H)‐dione, C24H28FNO2, (I), crystallizes with two crystallographically independent molecules (which differ slightly in conformation), while 10‐(4‐fluorophenyl)‐9‐propyl‐3,3,6,6‐tetramethyl‐3,4,6,7,9,10‐hexahydroacridine‐1,8(2H,5H)‐dione, C26H32FNO2, (II), crystallizes with one molecule per asymmetric unit. In both structures, the central ring in the acridine moiety is in a sofa conformation, while the outer rings adopt intermediate half‐chair/sofa conformations. The central pyridine ring is orthogonal to the substituted phenyl ring. In both structures, the packing of the crystal is stabilized by C—H?O intermolecular hydrogen bonds. 相似文献
27.
28.
Ishar MP Singh R Kumar K Singh G Velmurugan D Pandi AS Raj SS Fun HK 《The Journal of organic chemistry》2002,67(7):2234-2240
(E,E)-Arylidene-beta-ionones (1a-f) are converted to 1,7,7-trimethyl-3-(E-2'-arylethenyl)-2-oxabicyclo[4.4.0]deca-3,5-dienes (3a-f, approximately 90%) by irradiating in anhydrous solvents. Irradiation of (3a-f) in aqueous methanol results in Z,E-arylidene-beta-ionones (2), through retro-electrocyclization, which undergoes an intramolecular, exo-selective [4 + 2] photocycloaddition leading to 11-(exo)-aryl-1,7,7-trimethyl-tricyclo[4.4.0.1(2,4)]undec-5-ene-3-ones (8a-f, 60-80%). The latter rearrange over silica gel to afford, quantitatively, 5-aryl-7,11,11-trimethyl-tricyclo[5.4.0.0(3,6)]undec-1-ene-4-ones (5a-f). Irradiation of 1a-f in aqueous methanol leads to 8a-f, except in case of 1c,f wherein formation, respectively, of tricyclic ketones 9c (55%) and 9f (80%), derived from photodeconjugation in 2, followed by intramolecular [4 + 2] cycloaddition, is observed. 相似文献
29.
30.
R. Krishna D. Velmurugan S. Shanmuga Sundara Raj H.‐K. Fun P. C. Srinivasan 《Crystal Research and Technology》2001,36(11):1295-1301
The title compound crystallizes in monoclinic system with space group P21 /n. The cell parameters are a = 12.3824(3) Å, b = 8.9255(1) Å, c = 19.9188(4) Å, V = 2181.75(7) Å3 , α = γ = 90.0° and β = 97.663(1)°. The structure has an indole moiety and an imidazolidine ring connected together. The phenyl sulfonyl group is attached to the indole moiety and the dichlorophenyl ring to the imidazolidine ring. The structure has a C‐H … Cl intra molecular hydrogen bond and C‐H … π type intermolecular interactions. 相似文献