The title Schiff base compound, C(16)H(14)N(2)O(2), has been synthesized by the reaction of 5-amino-3,4-dimethyl-isoxazole and 2-hydr-oxy-1-naphthaldehyde. The dihedral angle between the isoxazole ring and the napthyl ring system is 3.29 (7)°. The mol-ecule adopts an E configuration about the central C=N double bond. Intra-molecular O-H⋯N hydrogen bonding generates an S(6) ring motif. In the crystal structure, π-π inter-actions are observed involving the isoxazole ring and the substituted benzene ring of the naphthyl unit, with centroid-centroid distances of 3.5200 (10) Å.
In the title mol-ecule, C(10)H(8)N(2)O, the five- and six-membered rings form a dihedral angle of 10.14 (9)°. The aldehyde group is almost coplanar with the pyrazole ring to which it is connected [O-C-C-C torsion angle = -179.35 (17)°]. In the crystal, inversion dimers are linked by four C-H⋯O inter-actions as the carbonyl O atom accepts two such bonds. The dimeric aggregates are linked into supra-molecular layers in the ac plane by C-H⋯π and π-π [ring centroid(pyrrole)⋯ring centroid(phen-yl) = 3.8058 (10) Å] inter-actions.
Polypyrrole (PPy) and Polypyrrole/MoS<sub>2</sub> (PPy/MoS<sub>2</sub>) nanocomposites were successfully prepared, characterized and studied for ammonia sensing properties. The as-prepared PPy and PPy/MoS<sub>2</sub> nanocomposites were confirmed by FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscopy) and TEM (transmission electron microscopy) techniques. The ammonia sensing properties of PPy and PPy/MoS<sub>2</sub> nanocomposites were studied in terms of change in DC electrical conductivity on exposure to ammonia vapors followed by ambient air at room temperature. It was observed that the incorporation of MoS<sub>2</sub> in PPy showed high sensitivity, significant stability and excellent reversibility. The enhanced sensing properties of PPy/MoS<sub>2</sub> nanocomposites could be attributed to comparatively high surface area, appropriate sensing channels and efficiently available active sites. The sensing mechanism is explained on the basis of simple acid-base chemistry of polypyrrole.
Graphene, a single layer 2-dimensional structure nanomaterial with unique physicochemical properties (e.g. high surface area, excellent electrical conductivity, strong mechanical strength, unparalleled thermal conductivity, remarkable biocompatibility and ease of functionalization), has received increasing attention in physical, chemical and biomedical fields. This article selectively reviews current advances of graphene based materials for biomedical applications. In particular, graphene based biosensors for small biomolecules (glucose, dopamine etc.), proteins and DNA detection have been summarized; graphene based bioimaging, drug delivery, and photothermal therapy applications have been described in detail. Future perspectives and possible challenges in this rapidly developing area are also discussed.
Abstract Novel steroidal (6 R )‐spiro‐1,3,4‐thiadiazoline derivatives have been synthesized by the cyclization of steroidal thiosemicarbazones. Thiosemicarbazones have been synthesized by the reaction of steroidal ketones with thiosemicarbazide. All the compounds have been characterized by IR, 1 H NMR, mass and elemental analyses. The antibacterial activities of these compounds have been first tested in vitro by the disk diffusion assay against two Gram‐positive and two Gram‐negative bacteria, and then the minimum inhibitory concentration (MIC) values have been determined with the reference of standard drug amoxicillin. The results showed that steroidal thiadiazoline derivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3 β ‐position of the steroidal thiadiazoline ring increased the anti‐bacterial activity. Among all the compounds, compounds 7 and 8 were found better inhibitors as compared to the respective drug amoxicillin.
Additional file 1. Cartesian co-ordinates of optimized geometries and cif files of 3a and 3b are given in supporting information. Experimental 1H,13C-NMR are also pasted in supporting information along with HOMOâ LUMO surfaces, simulated UVâ vis. Spectra and Tables containing bond length and bond angles data.
Copper oxide decorated multi-walled carbon nanotube nanocomposites (CuO·MWCNT NCs) were prepared using a simple wet-chemical technique in basic medium.
