Structures of 2-, 3-, and 4-methyl-9-oxothioxanthenes

The structures of 2-, 3-, and 4-methyl-9-oxothioxanthenes (2-, 3-, and 4-TX, respectively) were determined by single crystal x-ray methods. The molecules are folded by 2–3° about their SC=O lines. Bond distances and angles vary only slightly as a function of the methyl substitution position, and reveal no inherent structural reason for the long-range nmr couplings observed between the ring and methyl protons. The molecular packings exhibit interesting similarities as well as subtle differences that result from variation of the methyl position. Crystals of 2-TX are orthorhombic, space groupPn2₁ a,a=10.807(1),b=4.024(2),c=24.827(3) Å,Z=4,R=0.059 for 715 observed reflections. Crystals of 3-TX are orthorhombic, space groupPbc2₁,a=3.999(1),b=25.051(2),c=10.758(1)Å,Z=4,R=0.041 for 1382 observed reflections. Crystals of 4-TX are triclinic, space groupP¯1,a=7.118(1),b=7.907(2),c=10.415(2) Å,=77.74(1),=74.35(1), =73.96(1)°,Z=2,R=0.043 for 1542 observed reflections.Deceased.     

Mesomorphic and Photoconducting Behavior of 2-(2-Hydroxy-4-alkoxybenzylideneamino)-9-methylcarbazoles

The mesomorphic properties of 2-(2-hydroxy-4-alkoxybenzylideneamino)-9-methyl-carbazoles were investigated and the photoconducting behavior of the crystalline, nematic and isotropic liquid phases were compared for the pentyloxy compound. It was found that the behavior in the nematic phase is comparable with that in the isotropic liquid phase, both being fluid, rather than that in the crystalline phase. The carrier transport mechanisms and the carrier species are implied to be ionic. The current-voltage characteristics showed a new behavior in the fluid states, being similar to that of the negative resistance.     

The Crystal and Molecular Structure of 1,8-Dioxo-9- (o-nitrophenyl)-1,2,3,4,5,6,7,8-octahydroxanthene

The crystal structure of the title compound is described. The compound crystallizes in monoclinic space group P21/a with Z=4. The unit cell dimensions are a = 10.809(2), b = 9.998(2) and c = 14.855(3) Å, V = 1592(1) ų, D_cal = 1.399 g/cm³. The central ring of the octahydroxanthene moiety is slightly folded and the two outer rings are in sofa conformations. Due to the p-conjugation there is an electron delocalized stretch. The phenyl ring of the 2-nitrophenyl substituent is perpendicular to the octahydroxanthene ring system.     

Inclusion Compounds of the Host 9-(4-Methylphenyl)-9<Emphasis Type="Italic">H</Emphasis>-xanthen-9-ol with a Series of Organic Guests

Abstract  The host 9-(4-methylphenyl)-9H-xanthen-9-ol (H) forms inclusion compounds with the guests cyclohexane (H · ?CHEX), benzene (H · ?BENZ), 1,4-dioxane (H · ?DIOX), cyclohexanone (H · CYONE), N,N-dimethylformamide (H · DMF) and N,N-dimethylacetamide (H · DMA). For those guest molecules possessing electron acceptor atoms/functionalities hydrogen bonding with the host is the prominent mode of interaction and presents itself in the form of (Host)–OH···O(Guest) linkages. The cyclohexane and benzene guests however, occupy voids created by neighbouring host molecules which form hydrogen bonded dimers of the form (Host)–OH···O(Host). The structures of the inclusion compounds were investigated and their thermal stabilities determined. Selectivity experiments were also conducted. Graphical Abstract  The host 9-(4-methylphenyl)-9H-xanthen-9-ol (H) forms inclusion compounds with the guests cyclohexane (H · ?CHEX), benzene (H · ?BENZ), 1,4-dioxane (H · ?DIOX), cyclohexanone (H · CYONE), N,N-dimethylformamide (H · DMF) and N,N-dimethylacetamide (H · DMA). Crystal structures and thermal stabilities were determined. The host selectivity was also investigated.      

Synthesis,crystal structure,and spectral studies of 10-(2-Benzothiazolylazo)-9-phenanthrol

10-(2-Benzothiazolylazo)-9-phenanthrol (L) is prepared by a reaction of 2-hydrazinobenzothiazol with 9,10-phenanthrenequinone. The crystal and molecular structure of the L·CHCl₃ solvate is determined by X-ray diffraction. The data of the X-ray diffraction study, as well as IR, ¹H NMR, and electronic absorption spectra, indicate that in the crystal state and solutions the L molecule exists in the form of a quinohydrazone tautomer (b) (s-trans, cis) stabilized by the intramolecular N₂-HN₂…O1 hydrogen bond. The “mobile” H atom is located at the N2 atom of the azo group. The benzothiazolyl and phenanthrenequinone fragments are nearly coplanar. Spectroscopic criteria for the state of L in various media are determined based on the data of IR, ¹H NMR, and electronic absorption spectroscopy and the results of the Pariser-Parr-Pople quantum-chemical calculations.     

9-(2-Methylphenyl)-3,4,5,6,9,10-hexa- hydroxanthene-1,8(2H,7H)-dione

Several 9-(2-R phenyl)xanthenediones have been synthesized and the x-ray diffraction structure for the 2-methylphenyl derivative (4b) has been determined. This compound crystallizes in the monoclinic system, space group P2₁/n, with a = 11.729 (3), b = 9.674 (3), c = 14.628 (4) Å, and = 106.30°. It presents a partially hydrogenated xanthene system in distorted boat conformation for the heterocyclic central ring, and an almost ideal envelope conformation for the outer rings. The aromatic substituent at the ninth position is at 84° in angle with the xanthene system.     

Microwave Assisted Synthesis and Crystal Structure of 3,3,6,6-Tetramethyl-9-(phenyl)-1,8-dioxo-2,3,4,5,6,7-hexahydroxanthene

Abstract  The title compound (C₂₃H₂₆O₃, M _r  = 350.44) has been synthesized under microwave irradiation. Its structure was characterized by IR, ¹H NMR spectroscopy and single-crystal X-ray diffraction. The title crystal is in the monoclinic system, space group C with cell dimensions of a = 6.0500(12) ?, b = 19.693(4) ?, c = 16.386(3) ?, β = 97.85(3)o, V = 1,934.0(7) ?³, Z = 4, D _c  = 1.204 g/cm³, λ = 0.71073 ?, μ = 0.08 mm⁻¹, F ₍₀₀₀₎ = 752, the final R = 0.065 and wR = 0.165 for 1,992 observed reflections with I > 2σ(I). In the molecular structure, the pyran ring is of boat conformation, and the two-six-membered rings fused with it adopt envelope conformations. Index Abstract  The title compound (C₂₃H₂₆O₃, M _r  = 350.44) has been synthesized under microwave irradiation. Its structure was characterized by IR, ¹H NMR spectroscopy and single-crystal X-ray diffraction. The title crystal is in the monoclinic system, space group P2₁/C with cell dimensions of a = 6.0500(12) ?, b = 19.693(4) ?, c = 16.386(3) ?, β = 97.85(3)o, V = 1934.0(7) ?³, Z = 4, D _c  = 1.204 g/cm³, λ = 0.71073 ?, μ = 0.08 mm^–1, F ₍₀₀₀₎  = 752, the final R = 0.065 and wR = 0.165 for 1,992 observed reflections with I > 2σ(I). In the molecular structure, the pyran ring is of boat conformation, and the two six-membered rings fused with it adopt envelope conformations.      

9[1-(2-Hydroxy ethoxy)-3-hydroxy propyl] guanine: a nucleoside analog

The compound 9[1-(2-hydroxy ethoxy)-3-hydroxy propyl] guanine crystalizes in the tetragonal system, space group P4₁2₁2 with a = 11.106 (1), c = 20.558 (2) Å, and Z = 8. The acyclic chain C1¯O1¯C4¯C5¯O5 is in the extended configuration and the glycosidic torsion angle (C4¯N9¯C1¯O1) is 125.1 (8)°. The molecules are held together by Van der Waal's forces.     

The Synthesis,X-ray Structure Analysis and Photophysical Characterization of 2-(9-Anthrylmethylideneamino)-5-methylphenol

Abstract  

The Schiff base 2-(9-anthrylmethylideneamino)-5-methylphenol has been prepared in good yield (55%) from commercially available starting materials. The photophysical properties of this compound and its precursor have been determined. The room temperature absorption spectra of both in various solvents exhibited two π → π* transitions that had similar maxima, one that was more intense at approximately 260 nm and a weaker one at approximately 400 nm. Solutions of both compounds in methylcyclohexane and propanenitrile were luminescent at room temperature with maxima in the range 450–500 nm. The emission spectra of both at 77 K in methylcyclohexane solution were similar and exhibited vibrational structure with maxima in the range 460–522 nm. At room temperature and 77 K both compounds had short excited state lifetimes that characterized their emission as fluorescence. The title compound, C₂₂H₁₇NO, crystallized in the triclinic space group P[`\text1] P{\bar{\text{1}}} with a = 8.5533 (5) ?, b = 14.0926 (10) ?, c = 14.9382 (11) ?, α = 104.204 (6)°, β = 106.480 (5)°, γ = 105.091 (5)°, V = 1564.9 (2) ?³, T = 90 K, D _c = 1.322 Mg m⁻³, Z = 4, R = 0.033.     

Knoevenagel condensation of the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione with 9-anthracenecarboxaldehyde: Synthesis of the second-generation ligand 2-(anthracen-9-ylidene)-4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione

The Knoevenangel condensation between 9-anthracenecarboxaldehyde and the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione (bpcd) takes place rapidly in CH₂Cl₂/MeOH solution in the presence of molecular sieves (4 ?) to produce the functionalized ligand 2-(anthracen-9-ylidene)-4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione. The title compound has been isolated and characterized in solution by IR, NMR, and UV-vis spectroscopies, and the solid-state structure has been established by X-ray diffraction analysis. 2-(anthracen-9-ylidene)-4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione crystallizes in the triclinic space group P−1, a=10.227(2) ?, b=13.865(2) ?, c=15.905(2) ?, α=112.157(2)°, β=101.424(2)°, γ=100.065(3)°, V=1968.5(5) ?³, Z=2, and d _calc=1.101 Mg/m³; R=0.0873, R _w=0.2604 for 7452 reflections with I>2σ(I). The cyclic voltammetric behavior for 2-(anthracen-9-ylidene)-4,5-bis(diphenylphosphino)-4-cyclopentene-1,3-dione has been studied, and the observed redox data and results from extended Hückel MO calculations are discussed relative to the parent ligand bpcd.

Crystal structure and conformation of Tilorone monohydrate [2,7-{bis1-oxo-4-(1-piperidinyl)butyl}-9H-fluoren-9-one] monohydrate: an antiviral agent and an interferon inducer

Tilorone is an orally active pharmacological agent that protects mice against infections with RNA and DNA viruses. It is also the only known small molecule that is an interferon inducer. It has anti-tumor and anti-inflammatory properties and was shown to interact and influence the immune mechanisms in human and animals. Structure-function studies of Tilorone and its several analogs have been undertaken in our laboratories with an objective to correlate the structural features with the immuno-suppressive activity. Crystals of the title compound are triclinic, space group , with the following crystallographic parameters: a = 7.068(2), b = 9.030(3), c = 23.635(3) Å, = 103.91(2), = 108.49(2), = 93.84(4)°, V = 1371.9 ų, _obs = 1.17 Mg/m³, _calc = 1.168 Mg/m³ and Z = 2. The structure was solved with CAD-4 data, using SHELX-86 program and refined to a final R value of 0.063. The oxobutyl groups are in an extended zig-zag conformation and are co-planar with the central fluorenone chromophore. The two terminal piperidine rings are in the preferred chair conformation. The crystal structure lends support to the intercalative mechanism of action for Tilorone. We hypothesize that the stereochemistry and molecular geometry of these drugs and/or their active metabolites affect both the receptor interaction and the mode of immunomodulation. Comparison of the biological effects of the various tilorone analogs should allow us to obtain some more insight into their structure-function correlations.     

Synthesis,Characterization, and Crystal Structure of 3,3,6,6-Tetramethyl-9-(4-Methoxyphenyl)-10-(4-Chlorophenyl)-1,8-Dioxodecahydroacridine Dimethyl Sulfoxide

Crystallography Reports - By following one-pot synthesis, an acridinediones derivative compound 3,3,6,6-tetramethyl-9-(4-methoxyphenyl)-10-(4-chlorophenyl)-1,8-dioxodecahydroacridine dimethyl...     

Three-Six-Membered Rings with Diverse Conformations in the Structure of 9-(4-Methoxyphenyl)-3,3-Dimethyl-10-(4-Methylphenyl)-1,2,3,4,5,6,7,8,9,10-Decahydroacridin-1,8-Dione

Abstract  

The crystal structure of 9-(4-methoxyphenyl)-3,3-dimethyl-10-(4-methylphenyl)-1,2,3,4,5,6,7,8,9,10- decahydroacridin-1,8-dione is determined by X-ray diffraction at 153(2) K. The title compound 1, C₂₂H₂₁N₅O₆, is triclinic, space group P-1, a = 9.6382(15) ?, b = 11.5847(15) ?, c = 12.4722(11) ?, α = 66.075(9)°, β = 70.176(9)°, γ = 85.800(13)°, Z = 2, V = 1194.1(3) ?³. It is interesting that the central pyridine ring of the acridine moiety is slightly distorted and adopts a boat conformation. The outer six-membered ring with two methyl groups adopts half-chair conformation, while another outer partially saturated six-membered ring adopts distorted boat form. In addition, the un-classical hydrogen bonds of C–H···O link the molecules forming polymers in the crystals.     

Synthesis and Structure of 9-Bromo-2-fluoro-8-[ethyl, (E)-2-propenoate-3-yl]-6,7-dihydro-5H-benzocycloheptene

Abstract  

This paper reports a synthesis of 9-bromo, 2-fluoro substituted, and Z-ring locked (by a trimethylene bridge at C8 and C11) crystalline fluorine substituted bicyclic ring-fused polyene bearing a δ-bromo-α,β,γ,δ-unsaturated ester unit. It is a structural element found in sterically hindered retinoids and is a useful advanced intermediate in the total synthesis of these naturally occurring bioactive polyenes. The synthon, 8-fluoro-1-benzosuberone was converted into 9-bromo-2-fluoro-6,7-dihydro-5H-benzocycloheptene-8-carboxaldehyde chemoselectively and regioselectively and then into 9-bromo-2-fluoro-8-[ethyl, (E)-2-propenoate-3-yl]-6,7-dihydro-5H-benzocycloheptene in a step economical and stereoselective manner by treatment with triethylphosphonoacetate and NaH in THF. The process creates a new carbon–carbon double bond between C12 and C13 and produces a previously unreported product that has been characterized by X-ray, IR, ¹H NMR, ¹³C NMR, GC–MS, and elemental analysis. Crystals are triclinic, space group P-1, a = 7.581(2), b = 8.324(2), c = 11.759(3) ?, α = 96.723(17), β = 96.056(16), γ = 101.999(17)°, Z = 2.     

Efficient deep blue organic light emitting diodes based on [2,7,7,13,13-pentamethyl-9-(10-phenylanthracen-9-yl)-7,13-dihydrobenzo[5,6]-s-indaceno[1,2-g]quinoline] derivatives

Abstract

In this study, as the ongoing effort to develop efficient blue OLEDs, two deep blue emitters based on indenoquinoline-substituted anthracene derivatives have been synthesized and characterized. Multilayer organic light emitting diodes were fabricated with the following sequence: indium-tin-oxide (ITO)/4,4’,4’’-tris[2-naphthyl(phenyl)amino (2-TNATA)/4,4’-bis(N-(1-naphthyl)-N-phenylamino) biphenyl (NPB)/Blue emitting materials/Bathophenanthroline (Bphen)/lithium quinolate (Liq)/Al. All the devices showed efficient blue emissions. Particularly, a device using ‘2,7,7,13,13-pentamethyl-9-(10-phenylanthracen-9-yl)?7,13-dihydrobenzo[5,6]-s-indaceno[1,2-g] quinoline’ as an emitter showed a maximum external quantum efficiency (EQE) of 4.92% with the Commission Internationale De L’Énclairage (CIE) coordinates of (0.15, 0.10) at 8.0?V.     

Crystal and Molecular Structure of 9-Methyl-3,4,6,7,910-hexahydro-2,2,8,8-tetramethyl 1,8-(2H,5H)- acridine-dione

The crystal structure of the title compound was determined from X-ray diffraction data using direct methods. The crystals are tetragonal, a = b = 17.618 (1) A, c = 10.121(2) A, Z = 8, V = 3141.5(7) A³, space group P4(2)/n. The structure was refined by full-matrix least-squares to a final R value of 0.052. The central dihydropyridine ring is nearly planar while the outer two rings adopt half chair conformation.     

Crystal structure of a nucleoside analog: 9-(R)-[6-(R)-hydroxymethyl-1-oxa-4-thiacyclohexan-2-yl] adenine

The title compound (C₁₀H₁₃N₅O₂S,M _r=267.3) crystallizes in the orthorhombic space groupP2₁2₁2₁ witha=7.579(8),b=7.686(2) andc=20.941(4)Å,V=1220(1)ų,D _x=1.456 gm cm^–3,Z=4,=23.6 cm^–1,F(000)=560 andT=293 K. The structure was solved by direct methods and refined to aR value of 0.068 for 776 unique observed reflections. The oxathiane ring adopts a chair conformation. In the crystal structure the molecules are held together by hydrogen bonds and C-HO close contacts.