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A green electrospinning was used for the fabrication of PVA/Dex (dextran sulfate) nanofibers as a carrier for drug delivery. Core-shell nanofibers were fabricated by emulsion electrospinning from PVA/Dex loaded with ciprofloxacin (Cipro) as a model drug. The ratio of the PVA/Dex mixture was optimized and nanofibers were stabilized against disintegration in water by thermal treatment at 120 °C. The morphology of the prepared nanofibers was observed by scanning electron microscopy (SEM) and the core-shell structure of the nanofibers was confirmed by transmission electron microscopy (TEM). Drug entrapment was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). The interaction between PVA and Dex was affirmed by differential scanning calorimetry (DSC). In vitro drug release was monitored by UV-vis spectrophotometer and its associated mechanism was studied using diverse kinetic models. The release study demonstrated that the core-shell nanofibers can sustain the Cipro release compared with the blending electrospinning nanofibers. Moreover, the drug release mechanism is controlled by the Dex content of the polymer blends and can occur by diffusion within the delivery system. It is anticipated that Cipro@PVA/Dex nanofibers are promising eco-friendly drug delivery system which can be prepared by a green method., (Copyright © 2018 Elsevier B.V. All rights reserved.)

FT-Raman and FT-IR spectra were recorded for1-(5-methyl-[1,3,4]thiadiazol-2-yl)-pyrolidin-2-ol (MTPN) sample in solid state. The equilibrium geometries, harmonic vibrational frequencies, IR and the Raman scattering intensities were computed using DFT/6-311++G (d,p) level. Results obtained at this level of theory were used for a detailed interpretation of the IR and Raman spectra, based on the TED of the normal modes. Molecular parameters such as bond lengths, bond angles and dihedral angles were calculated. The intra-molecular charge transfer was calculated by means of NBO. Hyperconjugative interaction energy was more during the π-π(∗) transition. Energy gap of the molecule has been found using HOMO and LUMO calculation, hence the less band gap, which seems to be more stable., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In the title compound, C17H21ClN2O6, the di-hydro-pyrimidine ring adopts a flattened envelope conformation, with the sp (3)-hybridized C atom forming the flap. The dihedral angle between the least-squares planes of the benzene and di-hydro-pyrimidine rings is 88.09 (6)°. An intra-molecular C-H⋯O hydrogen bond generates an S(6) ring. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif, and the dimers are linked via further pairs of N-H⋯O hydrogen bonds, forming R 2 (2)(14) rings and chains of mol-ecules along [111]. Pairs of inversion-related chains are linked via weak C-H⋯π inter-actions.

In the title compound, C16H18N2O2S, the morpholine ring adopts a chair conformation. The thio-phene ring makes a dihedral angle of 63.54 (14)° with the mean plane of the four C atoms [maximum deviation = 0.010 (3) Å] of the morpholine ring. The benzamide ring is disordered, with four C atoms occupying two sets of sites, with a refined occupancy ratio of 0.502 (4):0.498 (4). These two rings are inclined to one another by 85.2 (4)° and to the thio-phene ring by 72.7 (3) and 13.0 (3)° for the major and minor components, respectively. In the crystal, mol-ecules are linked via N-H⋯O hydrogen bonds, forming chains along [001].

The experimental and theoretical vibrational frequencies of a newly synthesized compound, namely 1-(quinolin-3-yl)piperidin-2-ol (QPPO) are analyzed. The experimental FT-IR (4000-400 cm(-1)) and FT-Raman (4000-100 cm(-1)) of the molecule in solid phase have been recorded. The optimized molecular structure, vibrational assignments of QPPO have been investigated experimentally and theoretically using Gaussian03W software package. The stability of the molecule arising from hyper-conjugative interaction and charge delocalization has been analyzed using NBO analysis. The first order hyperpolarizability (β0) is calculated to find its character in non-linear optics. Gauge including atomic orbital (GIAO) method is used to calculate (1)H NMR chemical shift calculations were carried out and compared with experimental data. The electronic properties like UV-Visible spectral analysis and HOMO-LUMO energies were reported. The energy gap shows that the charge transfer occurs within the molecule. Thermodynamic parameters of the title compound were calculated at various temperatures., (Copyright © 2015 Elsevier B.V. All rights reserved.)

In the title compound, C17H22N2O6, the di-hydro-pyrimidine ring adopts a flattened boat conformation. The dihedral angle between the benzene ring and the mean plane of the di-hydro-pyrimidine ring is 75.25 (6)°. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R 2 (2)(8) ring motif which are linked through N-H⋯O and weak C-H⋯O hydrogen bonds. These, together with π-π ring inter-actions [centroid-centroid distance = 3.7965 (10) Å], give an overall three-dimensional structure.

In the title hydrated salt, C13H10Cl2N3O(+)·Cl(-)·3H2O, the organic cation exhibits a dihedral angle of 8.26 (14)° between the mean planes of the pyridinium and benzene rings, and dihedral angles of 8.70 (15) and 15.93 (5)° between the mean planes of the hydrazide group and the benzene and pyridinium rings, respectively. In the crystal, N-H⋯O, N-H⋯Cl, C-H⋯O, C-H⋯Cl, O-H⋯O, O-H⋯N and O-H⋯Cl hydrogen bonds link the complex cations, chloride anions and solvent water mol-ecules into a three-dimensional network.

In the title compound, C12H14N2O2S2, the di-hydro-pyrimidine ring adopts a sofa conformation, with the C atom bearing the thienyl ring lying above the plane of the five remaining approximately coplanar (r.m.s. deviation = 0.0405 Å) atoms of the ring. The dihedral angle between the five near coplanar atoms of the ring and the thienyl ring is 89.78 (11)°. In the crystal, mol-ecules are linked into a supra-molecular chain along [100] via N-H⋯O(carbon-yl) hydrogen bonds. Inversion-related chains are linked into double chains via N-H⋯S(thione) hydrogen bonds. The three-dimensional architecture also features meth-yl-thienyl C-H⋯π inter-actions.

In the title compound C18H20N2O2, the morpholine ring adopts a chair conformation with the exocyclic N-C bond in an equatorial orientation. The N atom of the morpholine ring and the C atom of the carbonyl group are in an anti conformation about the central C-C bond [torsion angle = -162.92 (11)°] and the dihedral angle between the planes of the benzene ring and the pyridine ring is 83.30 (5)°. In the crystal, pairs of very weak C-H⋯π inter-actions link the mol-ecules into inversion dimers.

In the title compound, C14H14Cl2N2O3, the chloro-phenyl ring makes a dihedral angle of 87.08 (9)° with the tetra-hydro-pyrimidine ring. There is a short intra-molecular C-H⋯O contact present. In the crystal, mol-ecules are linked via pairs of N-H⋯O hydrogen bonds, forming inversion dimers with an R (2) 2(8) ring motif. The dimers are linked via a second pair of N-H⋯O hydrogen bonds, this time enclosing an R (4) 4(20) ring motif, forming ribbons along [100]. The ribbons are linked via C-H⋯O hydrogen bonds, forming sheets lying parallel to (001). The terminal ethyl group is disordered over two positions with an occupancy ratio of 0.654 (17):0.346 (17).

In the title hydrated compound, C15H15N3O3·H2O, the nicotinohydrazide mol-ecule adopts a trans conformation with respect to the C=N double bond. The dihedral angle between the benzene and pyridine rings is 5.10 (14)°. In the crystal, the solvent water mol-ecule acts as an acceptor, forming an N-H⋯O hydrogen bond supported by two C-H⋯O contacts. It also acts as a donor, forming bifurcated O-H⋯(O,O) and O-H⋯N hydrogen bonds that combine with the former contacts to form zigzag chains of mol-ecules along the c-axis direction. An additional O-H⋯O donor contact completes a set of six hydrogen bonds to and from the water mol-ecule and connects it to a third nicotinohydrazide mol-ecule. This latter contact combines with weaker C-H⋯O hydrogen bonds supported by a C-H⋯π contact to stack mol-ecules along b in a three-dimensional network.

The Spectral Characterization of (E)-1-(Furan-2-yl) methylene)-2-(1-phenylvinyl) hydrazine (FMPVH) were carried out by using FT-IR, FT-Raman and UV-Vis., Spectrometry. The B3LYP/6-311++G(d,p) level of optimization has been performed on the title compound. The conformational analysis was performed for this molecule, in which the cis and trans conformers were studied for spectral characterization. The recorded spectral results were compared with calculated results. The optimized bond parameters of FMPVH molecule was compared with X-ray diffraction data of related molecule. To study the intra-molecular charge transfers within the molecule the Lewis (bonding) and Non-Lewis (anti-bonding) structural calculation was performed. The Non-linear optical behavior of the title compound was measured using first order hyperpolarizability calculation. The atomic charges were calculated and analyzed., (Copyright © 2013 Elsevier B.V. All rights reserved.)

In the title compound, C14H13N3O2·2H2O, the hydrazone mol-ecule adopts an E conformation with respect to the C=N bond. The dihedral angle between the benzene and pyridine rings is 8.55 (10)°. The methyl-idene-hydrazide [-C(=O)-N-N=C-] fragment is essentially planar, with a maximum deviation of 0.0375 (13) Å. The mean planes of the benzene and pyridine rings make dihedral angles of 2.71 (14) and 11.25 (13)°, respectively, with mean plane of the methyl-idene-hydrazide fragment. In the crystal, the benzohydrazide and water mol-ecules are linked by N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds into a three-dimensional network.