An X-Ray Crystallographic Study of <Emphasis Type="Italic">N</Emphasis>-Methyl-3-nitro-4-(nitromethyl)-4<Emphasis Type="Italic">H</Emphasis>-chromen-2-amine

Abstract  

4H-chromenes are among the essential groups of biologically important compounds used as synthetic ligands for drug designing and discovery process. In this study, we have presented the single-crystal structure analysis of racemic 4H-chromene derivative namely N-methyl-3-nitro-4-(nitromethyl)-4H-chromen-2-amine. The optical rotation measurement data is supporting that the title compound is racemic in nature. The compound was crystallized in monoclinic crystal system in the non-centrosymmetric space group P2₁ with unit cell parameters a = 5.1041 (3), b = 7.7519 (4), c = 14.7974 (8), α = 90°, β = 97.088 (5)° and γ = 90°. The nitro group of title compound is disordered over two orientations (N3A/O4A/O5A & N3B/O4B/O5B) with the refined site-occupancy ratio of 0.626(6)/0.374(6). The structure was solved by direct methods using the program SHELXS-97 and refined by SHELXL-97 with the full-matrix least square procedure to a final R-value of 0.0429 and Goodness of Fit (GooF) of 0.982. The molecules in the unit cell are stabilized by N–H···O and C–H···O types of hydrogen bonds. The intermolecular hydrogen bonds are forming C (6) motifs, which is observed to contribute the crystal packing stability. Moreover, the intramolecular hydrogen bonds are forming S (6) motif essential to stabilize the molecular structure of title compound.     

Synthesis,Characterization and Crystal Structure of (<Emphasis Type="Italic">S</Emphasis>)-2-(2-Hydroxynaphthalen-6-yl)-<Emphasis Type="Italic">N</Emphasis>-((pyridin-4-yl)methyl) Propanamide

Abstract  

The synthesis, characterization and crystal structure of the title compound, (S)-2-(2-hydroxynaphthalen-6-yl)-N-((pyridin-4-yl)methyl) propanamide, is described. The salt is enantiomerically pure and crystallize in the orthorhombic P2₁2₁2₁ chiral space group with a = 7.9174(13) ?, b = 11.1583(18) ?, c = 11.2600(18) ?. Each molecule is linked to four neighboring molecules through the O–H···O and N–H···N hydrogen bonds into a supramolecular helical chain. The O–H···O and N–H···N hydrogen bonds lead to 24-membered open rings. Chains are further connected into layers via extensive interchain H···O and H···C short contacts.     

Structure and Antibacterial Activity of 3-(3,4-Dimethoxyphenyl)furan-2(5<Emphasis Type="Italic">H</Emphasis>)-ones

Abstract  

Crystalline hydrate of the title compound (5), C₁₉H₂₆N₂O₅·2(H₂O), was structurally characterized by single crystal X-ray diffraction. It crystallizes in monoclinic system space group P 21/c with a = 7.3987(7) ?, b = 17.8691(16) ?, c = 17.0022(13) ?, β = 112.944(3)°, V = 2070.0(3) ?³, Z = 4, R ₁ = 0.0592, wR ₂ = 0.1016, and T = 298(2) K. The X-ray structure determination revealed that the center furanone ring is nearly coplanar with 3,4-dimethoxybenzene ring, making a dihedral angle of 0.860(69)°. Two kinds of centrosymmetric tetramers characterized by graph-set motifs of R ₇⁸(36) and R ₄⁶(32) are formed through O–H···O, O–H···N and C–H···O hydrogen bonding interactions, which generate a sheet of edge-fused rings parallel to the (011) plane. These sheets are further linked into a three dimensional network by C–H···π interactions. Nine 3-(3,4-dimethoxyphenyl)furan-2(5H)-ones were synthesized and fully characterized by elemental analysis, MS and ¹H NMR. All of them were evaluated for antimicrobial activities against three Gram-positive organisms and a Gram-negative organism, and compound 5 was the most active against Staphylococcus aureus ATCC 25923.     

Synthesis and Crystal Structures of Methyl 3-(Benzoylamino)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-5-carboxylate and <Emphasis Type="Italic">N</Emphasis>-[5-(3,4-Dimethoxyphenyl)-6-methyl-2-oxo-2<Emphasis Type="Italic">H</Emphasis>-pyran-3-yl]benzamide

Abstract  

The compounds methyl 3-(benzoylamino)-6-methyl-2-oxo-2H-pyran-5-carboxylate (1), C₁₅H₁₃NO₅, and N-[5-(3,4-dimethoxyphenyl)-6-methyl-2-oxo-2H-pyran-3-yl]benzamide (2), C₂₁H₁₉NO₅, crystallize as a centrosymmetric hydrogen-bonded dimer facilitated by N–H···O interactions involving the amide and carbonyl moiety of the lactone group of adjacent molecules. Supramolecular aggregation in 1 is controlled by a combination of π–π interactions [centroid–centroid distance = 4.0745(11) ?] and weak C–H···O hydrogen bonding between the phenyl ring of the benzoylamino group and the carbonyl atom of the methoxycarbonyl group and in 2 by a combination of π–π interactions [centroid–centroid distance = 4.0699(8) and 4.1556(10) ?], weak C–H···O interactions between the methoxy substituents of the adjacent dimethoxyphenyl group and weak C–H··· π interactions.     

Structures of Two (<Emphasis Type="Italic">E</Emphasis>)-3-Substituted Cinnamoylbenzotriazole 1-Oxides

Abstract  

The molecule of (E)-3-(3-MeOC₆H₄CH=CHCO)-benzotriazole 1-oxide, 2, has a very near planar structure, while the 2-nitrophenyl ring is rotated out of the plane of the remaining atoms in (E)-3-(2-O₂NC₆H₄CH=CHCO)-benzotriazole 1-oxide, 1. The nitrogen oxide bond lengths in 1 and 2 are 1.258 (6) and 1.2683 (15) ?, respectively, and are in the region found for related compounds. There are no strong intermolecular hydrogen-bonds in either compound, instead there are weak C–H···O intermolecular hydrogen-bonds and π···π stacking interactions in 1, and C–H···O, C–H···π, and π···π stacking interactions in 2. Different three-dimensional arrays are generated in each case. Compound 1 crystallises in the orthorhombic space group Pna2₁, with a = 25.061 (2) ?, b = 3.6997 (2) ?, c = 14.2623 (12) ? and Z = 4. Compound 2 crystallises in the triclinic space group P-1, with a = 5.7297 (3) ?, b = 10.8440 (6) ?, c = 11.4965 (6) ?, α = 89.689 (3)°, β = 76.019 (3)°, γ = 75.047 (3)°, Z = 2.     

Synthesis and Crystal Structure Analysis of Methyl 2-Hydroxyimino-3-phenyl-propionate

Abstract  

As precursors of α-amino acids, methyl 2-hydroxyimino-3-phenyl-propionate (F.W. 193.20) was synthesized, characterized by ¹H NMR, IR, element analysis and confirmed by X-ray crystal structure analysis. This compound crystallizes in monoclinic class under the space group P2₁/c with cell parameters, a = 8.6435(17) Å, b = 5.4957(11) Å, c = 21.146(4) Å; β = 97.12(3)°, and Z = 4. The structure exhibits inter-molecular hydrogen bonds of the type O–H···N, O–H···O, C–H···O.     

6-Chlorothieno[2,3-<Emphasis Type="Italic">e</Emphasis>]-1,4,2-dithiazine-3(2<Emphasis Type="Italic">H</Emphasis>)-thione-1,1-dioxide,Ammonium Salt Sesquihydrate: Synthesis,Crystal Structure and Density Functional Calculations

Abstract  

The title compound crystallizes in the monoclinic space group C2/c space group, with unit cell dimensions of a = 15.6684(3) ?, b = 7.3974(2) ?, c = 21.2669(5) ?; β = 106.7770(10)° (Z = 8). In the title compound, NH₄ ⁺·C₅HClNO₂S₄ ^–·1.5 H₂O, the 1,4,2-dithiazine ring adopts a distorted half-chair conformation. The structure displays several cooperative intermolecular N/O–H···N/O/S hydrogen-bonding interactions, giving rise to a two-dimensional layers packing motif. The layers are built up from seven component entities formed via extensive intermolecular N/O–H···N/O/S hydrogen bonds involving 6-chlorothieno[2,3-e]-1,4,2-dithiazine-3(2H)-thione-1,1-dioxide anions, ammonium cations and water molecules. The geometry of the title compound was fully optimized using a Density functional B3LYP/6-31G(d) and B3LYP/6-31+G(d) methods and the results were consistent with experimental values. The binding energy and associated basis set superposition as well as the thermodynamic quantities were calculated.     

Crystal Structure of 2-<Emphasis Type="Italic">Exo</Emphasis>-Phenyl-2,3,4,5-Tetrahydro-1,4-Epoxinafto[1,2-b]azepine

Abstract  

The title compound, C₂₀H₁₇NO, crystallizes in the orthorhombic P2₁2₁2₁ space group with unit cell parameters a = 7.6903(7) ?, b = 18.979(2) ?, c = 19.753(2) ?, with two crystallographically independent molecules in the asymmetric unit, which differ from one another in the slight rotation of the phenyl ring; this allows the formation of three internal hydrogen bonds, two of the type C–H···N and one of the type C–H···O, in one of the molecules, in contrast with only two of the type C–H···N in the other. The compound is rich in aromatic π rings and therefore the crystal packing is entirely dominated by cohesive weak C–H···π interactions among neighboring molecules producing an efficient packing with 71.2% of occupied space.     

The Synthesis and Structure of 2-Amino-4,6-dimethylpyrimidine 2-Hydroxybenzoate

Abstract  

The title compound, 2-amino-4,6-dimethylpyrimidine 2-hydroxybenzoate was studied by X-ray diffraction methods. This compound crystallized in a monoclinic system; space group P2(1)/n with the unit cell parameters a = 7.5380(14) ?, b = 20.246(4) ?, c = 9.2029(17) ?, β = 108.594(3), V = 1331.2(4), Z = 4. The hydroxybenzoic acid group has been protonated by the aminopyrimidine moiety. The neighbouring two pyrimidine are bridged by N3–H3A···N2 hydrogen bonds, and the constituting dimers are linked together to form a discrete unit, these units, in turn, are linked together by C–H···O interactions. The protonated N1 atom is attached to the carboxyl group (O2) of the neighbouring phenyl by a hydrogen bond, together with the N3–H3B···O3 hydrogen bond to form a eight-membered ring with graph-set notation R₂¹(8). The C5 and O1 through hydrogen bond forms a supramolecular chain along the b-axis, which is further strengthened by O1–H1···O3 hydrogen bond, bridging the hydroxide radical and carboxyl via hydrogen bonded rings, R₁¹(6).     

Crystal Structure and Spectroscopic Properties of <Emphasis Type="Italic">trans</Emphasis>-Dibromobis(1,2-ethanediamine)chromium(III) Perchlorate

Abstract  

The crystal structure of trans-[Cr(en)₂Br₂]ClO₄ (en = 1,2-ethanediamine) has been determined by a single-crystal X-ray diffraction study at 150 K. The complex crystallizes in the space group P[`1] P\overline{1} of the triclinic system with two mononuclear formula units in a cell of dimensions a = 6.853(4), b = 8.109(5), c = 12.475(8) ?, α = 81.006(10)°, β = 77.005(10)° and γ = 74.981(10)°. The Cr atom is in a slightly distorted octahedral environment, coordinated by four nitrogen atoms of two en ligands and two bromine atoms in trans axial positions. The mean Cr–N(en) and Cr–Br bond lengths are 2.079(3) and 2.4743(10)?, respectively. The five-membered rings are in stable gauche conformations with N1–Cr1–N2 and N3–Cr2–N4 angles of 82.81(11)° and 83.67(11)°, respectively. The crystal packing is stabilized by a network of N–H···O and N–H···Br hydrogen bonds. The infrared and electronic absorption spectra are consistent with the results of X-ray crystallography.     

Crystal Structure and Energy Optimization of Dichlorobis(ethylanthranilatonicotinamide)Zinc(II)

Abstract  

The title compound, C₃₀H₂₈Cl₂N₄O₆Zn, dichlorobis(ethylanthranilatonicotinamide)zinc(II) crystallized in a triclinic space group, P − 1, with cell parameters a = 7.787(3), b = 13.468(1), c = 15.735(1), α = 110.25(1), β = 95.11(1), γ = 99.32(1) and Z = 2, with the whole molecule being the asymmetric unit. In this compound, zinc is bound to two ethylanthranilatonicotinamide (EAN) ligands and two chloride ligands in a distorted tetrahedral configuration. The nitrogen of the nicotinamide ring participates in bonding with zinc through its lone pair while the anthranilate nitrogen remains free. In one of the two EAN ligands, the anthranilate and nicotinamide groups are nearly co-planar while in the other, the angle between the two is ~35.5°. The complex shows three hydrogen bonds, two being C–H···O bonds and the other being C–H···Cl bond. The amidic N–H groups do not participate in hydrogen bond formation as they are buried in the core structure and are not accessible for other groups for association. Both the C–H···O bonds occur from C–H bonds present on the twisted EAN moiety.     

Synthesis, Spectroscopic Characterization and Crystal Structure of a New Acetyl phosphorylamidate P(O)[NHC(O)C6H4(4-NO2)][N(CH(CH3)2)(CH2C6H5)]2

Abstract  

A new acetyl phosphorylamidate P(O)[NHC(O)C₆H₄(4-NO₂)][N(CH(CH₃)₂)(CH₂C₆H₅)]₂ has been synthesized and characterized by elemental analysis, ¹H, ¹³C and ³¹P NMR, IR and single crystal X-ray diffraction. Single crystal X-ray analysis shows that it belongs to triclinic system, space group P[`1] P\bar{1} , with a = 10.5868(16) Å, b = 11.8058(18) Å, c = 12.4364(19) Å, α = 65.410(3)°, β = 67.492(4)°, γ = 85.879(3)°, V = 1,298.6(3) Å³, and Z = 2. The intermolecular PO···HN hydrogen bond makes H-bonded dimer of molecule with Ci symmetry. In the crystal network, the dimers are aggregated in the chain arrays through π-stacking between p-NO₂–C₆H₄–C(O)–NH– moieties. Moreover, weak C–H···O and C–H···π interactions exist in the crystal network.     

5-Pyridine 4-yl-3H-(1,3,4) Oxadiazole-2 Thione Hydrochloride Monohydrate, (I), and 4 [5-Ethylsulfanyl)-(1,3,4) Thiadiazole-2-yl]-Pyridinium Perchlorate, (II)

Abstract  

The title compounds C₇H₈ClN₃O₂S, (I), and C₉H₁₀ClN₃O₄S_2, (II), both crystallize in monoclinic space group P2₁ /c with unit cell parameters (I) a = 7.9402(7), b = 10.6312(9), c = 11.7626(10), ?, β = 99.271(5)°, Z = 4 and (II) a = 5.1439(2), b = 9.0636(4), c = 27.1814 (7), ?, β = 95.116(2)°, Z = 4. In (I) the molecule consists of a 5-pyridine-4-yl group bonded to the carbon atom at the 5 position of (1, 3, 4) oxadiazole-2 thione hydrochloride monohydrate. The angle between the mean planes of the oxadiazole and pyridine rings is 9.6(6)°. Crystal packing in (I) is stabilized by strong N–H···O hydrogen bonds in concert with a solvent water molecule and weak O–H···Cl, O–H···S, N–H···Cl intermolecular interactions. The crystal structure of compound (II) consists of 4 [5-ethylsulfanyl)-(1, 3, 4) thiadiazole-2-yl]-pyridinium perchlorate, (C₉H₁₀N₃S₂)⁺(ClO₄)⁻, cation–anion pairs, containing strong intermolecular N–H···O hydrogen bonds and weak C–H···O and N–H···O intermolecular interactions operating between the ionic species that form a cooperative hydrogen-bonded, infinite chain O–H···O–H···O–H network which generates a sheet motif structure in the unit cell. It is also supported by weak intermolecular Cg···Cg π–π and Cl–O···Cg π-ring interactions which gives additional support to molecular packing stability in the unit cell. Geometry optimized MOPAC AM1 computational calculations on each compound provides support to the structural features in their respective crystal structures.     

Crystal Structure of 2′,3′-Di-<Emphasis Type="Italic">O</Emphasis>-Acetyl-5′-Deoxy-5-Fluorocytidine with N–H···(O,F) Proton Donor Bifurcated and (C,N)–H···O Bifurcated Acceptor Dual Three-Center Hydrogen Bond Configurations

Abstract  The title compound, C₁₃H₁₆O₆N₃F, features a central furan ring containing four carbon atom chiral centers with a 4-amino-5-fluoro-2-oxopyrimidine group, two acetyl groups and a methyl group bonded at the 2,3,4,5 positions, each in an absolute R configuration (2R,3R,4R,5R). It crystallizes in the monoclinic space group C2 with unit cell parameters a = 14.5341(3), b = 7.26230(10), c = 16.2197(3) ?, β = 116.607(2)°, Z = 4. An extensive array of intra and intermolecular hydrogen bond interactions dominate crystal packing in the unit cell highlighted by a relatively rare three-center proton-bifurcated donor N–H···(O,F) hydrogen bond interaction in cooperation with a second, (C,N)–H···O bifurcated acceptor three-center hydrogen bond in a supportive fashion. Additional weak Cg π-ring intermolecular interactions between a fluorine atom and the 4-amino-5-fluoro-2-oxopyrimidine ring in concert with multiple donor and acceptor hydrogen bonds significantly influence the bond distances, bond angles and torsion angles of the deoxy-5-fluorocytidine group. Comparison to a MOPAC computational calculation provides support to these observations. Index Abstract  Crystal structure of (2R,3R,4R,5R)-2-(4-amino-5-fluoro-2-oxopyrimidin-1(2H)-yl)-5-methyl-tetrahydrofuran-3,4-diyl diacetate with dual N–H···(O,F) proton donor bifurcated and (C,N)–H···O bifurcated acceptor three-center hydrogen bond configurations is reported and its geometric and packing parameters described and compared to a MOPAC computational calculation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystallographic and Conformational Analysis of [(<Emphasis Type="Italic">E</Emphasis>)-2-[(3-Chlorophenylimino)methy])-4-methoxyphenol]

Abstract  The crystal structure of C₁₄H₁₂ClNO₂ was determined by X-ray analysis. It crystallizes in the triclinic space group Pc with a = 12.5346(10) ?, b = 4.5101(3) ?, c = 12.0534(11) ?, α = 90.00o, β = 113.669(6)o, γ = 90.00o, Z = 2, Dx = 1.393 mg/m³, μ (MoK_α) = 0.298 mm⁻¹. The title compound is photochromic and molecule is non-planar. It adopts a phenol–imine tautomeric form with a strong intramolecular O–H···N hydrogen bond and a strong intermolecular C–H···O hydrogen bond. Minimum energy conformations AM1 were calculated as a function of the three torsion angles θ1(C10–C9–N1–C8), θ2(C9–N1–C8–C1) and θ3(N1–C8–C1–C6), varied every 10°. As in the X-ray experiment results, molecule has an angle that makes it non-planar between two aromatic rings in AM1 optimized geometry. Graphical Abstract  Molecular and crystal structure of [(E)-2-[(3-chlorophenylimino)methy])-4-methoxyphenol], C₁₄H₁₂ClNO₂, have been determined by single crystal X-ray diffraction study, and conformational analysis of the title molecule with respect to the selected torsion angle has been achieved by AM1 semi-empirical calculations.      

Structure of a New Bioactive Agent Containing Combined Antibacterial and Antifungal Pharmacophore Sites: 4-{[(<Emphasis Type="Italic">E</Emphasis>)-(5-Bromo-2-hydroxyphenyl)methylidene]amino}-<Emphasis Type="Italic">N</Emphasis>-(5-methyl-1,2-oxazol-3-yl)benzenesulfonamide

Abstract  

The title compound (3), C₁₇H₁₄BrN₃O₄S, is a Schiff base compound of 5-bromosalicylaldehyde (1) and sulfamethoxazole (2). The structure of (3) was determined by spectral (IR, ¹H and ¹³C NMR), elemental analyses and X-ray diffraction data. Compound (3) crystallizes in the monoclinic space group C2/c, with a = 31.936(3), b = 6.2571(5), c = 16.903(1) ?, β = 94.867(8), V = 3365.5(5) ?³, Z = 8. In the molecule of compound (3), the molecule is bent at the S atom with a C–SO₂–NH–C torsion angle of −86.3(3)°. Pairs of molecules, related by inversion centres, form intermolecular N–H···N hydrogen bonds to produce a dimer. An intramolecular phenolic O–H···N hydrogen bond is also formed. Intermolecular hydrogen bonding and π–π stacking hold the molecules together. The average distance between stacked benzene ring planes is 3.625(2) ?.     

Hydrogen Bonded 3D Supramolecular Architectures of Two Organic Salts Assembled from 2-Aminoheterocyclic Compounds and Phosphoric Acid

Abstract  

Two phosphate salts (2-aminopyrimidine): (phosphoric acid): H₂O [HL1⁺ (H₂PO₄) ⁻ ]·H₂O (1), and (4-phenylthiazol-2-amine): (phosphoric acid) [HL2⁺·(H₂PO₄)⁻] (2) based on 2-aminoheterocyclic compounds, 2-aminopyrimidine (L1), and 4-phenylthiazol-2-amine (L2) were prepared and structurally characterized by X-ray crystallography. Compound 1 crystallizes in the triclinic, space group P-1, with a = 6.2201(7) Å, b = 8.6139(9) Å, c = 9.4800(10) Å, α = 109.685(2)°, β = 106.3340(10)°, γ = 95.4450(10)°, V = 448.72(8) Å³, Z = 2. For 1, the cations were linked to each other via intermolecular C–H···N hydrogen bonds to form a 1-D chain structure running along the a-axis direction. The anions and the water molecules were connected alternatively along the a-axis direction through O–H···O hydrogen bonds to form a 1-D chain also. The cationic chains and the anionic chains were alternatively connected along the c-axis direction through N–H···O and C–H···O hydrogen bonds to form a 2D corrugated sheet. Adjacent sheets were combined together through π–π interaction to form double sheet. These double sheets were further joined together by O–H···O and N–H···O hydrogen bonds to produce a 3D network structure. Compound 2 crystallizes in the Orthorhombic, space group Pbca, with a = 10.1929(10) Å, b = 8.4406(9) Å, c = 27.589(2) Å, α = 90°, β = 90°, γ = 90°, V = 2373.6(4) Å³, Z = 8. In 2, the phosphates formed 1D chain along the b-axis through two P–O–H···O = P hydrogen bonds. The cations formed 1D zigzag chain along the b-axis direction under the CH–π interaction. The anionic chains were intercalated between two adjacent cationic chains through N–H···O, O–H···O, C–H···O, and O–S contacts. Such stacking repeated along the c-axis direction to form a 3D network structure.     

Crystal Structure?4-(2,4-Dihydroxybenzylideneamino)-5-methyl-2H-1,2,4-triazol-3(4H)-one

Abstract  

The title compound (I), 4-(2,4-dihydroxybenzlideneamino)-5-methyl-2H-1,2,4-triazol-3(4H)-one was characterized by single crystal X-ray diffraction. This crystal is monoclinic, space group P2₁/c with a = 10.1447(7) ?, b = 7.0972(3) ?, c = 14.6726(10) ?, β = 98107(5)°, V = 1045.85(11) ?³, Z = 4, D _c = 1.487 g/cm³, F ₀₀ = 488, R = 0.039 and wR = 0.1025, S = 1.003, T = 293 (2) K. The title molecule is planar: the angle between the triazole ring and benzene ring is 179.1(1)°. The crystal structure contains two intramolecular (O–H···N and C–H···O) and three intermolecular interaction (O–H···N, N–H···O, and C–H···O). In addition, there is also π–π interactions.     

One Dimensional Hydrogen Bonded Arrangement in New Schiff-Base Compound (<Emphasis Type="Italic">E</Emphasis>)-2-(2,5-dimethoxybenzylideneamino)phenol (1): Synthesis,Characterization, Crystal Structure and Conformational Studies

Abstract  

New Schiff-base compound (E)-2-(2,5-dimethoxybenzylideneamino)phenol (1) was synthesized and characterized by elemental analyses, FT-IR and ¹H-NMR spectroscopy and single crystal X-ray diffraction. Molecular orbital calculation has been carried out for 1 by using HF method at 6-31G basis set. The title compound 1 crystallizes in monoclinic system, space group C2/c, with a = 19.4581(13) ?, b = 9.5805(5) Ǻ, c = 13.8431(7) Ǻ, β = 93.471(2)°, V = 2575.9(3) Ǻ³ and Z = 8. In the crystal structure two molecules are stabilized by a pair of intermolecular O1–H1···N1ⁱ hydrogen bonds. The dimeric units are further linked via C6–H6···O3ⁱⁱ hydrogen bond.     

Spectral and X-ray Diffraction Studies of <Emphasis Type="Italic">N</Emphasis>-(2-Nitrophenyl)-5-Phenyl-1,3,4-Oxadiazole-2-Amine

Abstract  

Thiosemicarbazides and their derivatives are well known for their use in biological activity and many applications in pharmaceutical and industrial fields. The cyclization of 1-benzoyl-4-(2-nitrophenyl)-3-thiosemicarbazide (BNPTSC) in dimethylformamide (DMF) medium furnished N-(2-nitrophenyl)-5-phenyl-1,3,4-oxadiazole-2-amine (NPPOA). The chemical structure of the above substituted 1,3,4-oxadiazole has been assigned by IR, mass and X-ray diffraction studies. The XRD studies reveal the presence of four types of hydrogen bonds (N–H···O, N–H···N, C–H···O, C–H···N) in the crystal packing. The crystal system was found to be orthorhombic with a space group Pca2(1) and the unit cell dimensions are: a = 26.873(3) ?, b = 6.0827(7) ?, c = 7.8502(10) ?, α = 90°, β = 90°, γ = 90° and Z = 4.