Chromene Carbohydrazide- Schiff Base as a Highly Selective Turn-Off Fluorescence Chemosensor for In3+ Ion and its Application.

A new 7-(diethylamino)-2-oxo-2 H-chromene-3-carbohydrazide design to synthesize a simple Schiff-base condition. The synthesized molecules' (probe L) photophysical properties were investigated in various solvent systems and solvent-poor-solvent assays. Probe L exhibits the absorbance band at 440 nm and the emission band at 488 nm in DMSO: H2O (7:3, v/v). Further, probe L shows selective turn-off emission recognition of In3+ ions in DMSO: H2O (7:3, pH = 7.4). By Job's plot and ESI mass analysis, probe L forms a 1:2 stoichiometry complex with an estimated association constant of 4.04 × 104 M- 2 with In3+ ions. Metal induces CHEQ (chelation-caused fluorescence quenching) to reduce the intensity of probe L's emission, and the estimated quenching constant was 4.52 × 104 M- 1. The limit of detection was found to be 5.93 nM; the time response of the sensor is instantaneous, and its reversible nature was confirmed using EDTA additions. Solid substrates (test strips) were designed and tested for fast, reliable, user-friendly, and real-time sensing of In3+ ions for on-site applications. The binding mechanism of probe L with In3+ ions was investigated using 1H NMR titration and DFT/TD-DFT studies.

Crystal structure of 5-di-ethyl-amino-2-({[4-(di-ethyl-amino)-phen-yl]imino}-meth-yl)phenol.

In the title compound, C21H29N3O, the dihedral angle between the planes of the aromatic rings is 8.1 (2)°. The ethyl groups at one terminal site of the compound are disordered over two sets of sites with occupancies of 0.775 (9) and 0.225 (9). The mol-ecule has an E conformation about the N=C bond. The mol-ecular structure features an intra-molecular O-H⋯N hydrogen bond, which closes an S(6) loop. In the crystal, weak C-H⋯π inter-actions leads to the formation of a three-dimensional network.

Crystal structure of (E)-5-di-ethyl-amino-2-({[4-(di-methyl-amino)-phen-yl]imino}-meth-yl)phenol.

The title Schiff base compound, C19H25N3O, is approximately planar, with a dihedral angle of 9.03 (13)° between the planes of the aromatic rings, and has an E conformation about the N=C bond. The mol-ecular structure is stabilized by an intra-molecular O-H⋯N hydrogen bond, with an S(6) ring motif. In the crystal, mol-ecules are linked by C-H⋯π inter-actions, forming sheets parallel to the bc plane.

Synthesis, characterization, crystal structure and cytotoxic properties of thiosemicarbazide Ni(II) and Zn(II) complexes.

Synthesis of new complexes of Ni(II) (1) and Zn(II) (2) with [1-(2-hydroxy-3,5-diiodobenzylidene)-4-phenylthiosemicarbazide] have been reported. The composition of these two complexes 1 and 2 is discussed on the basis of IR, (1)H NMR and UV spectral data along with their X-ray crystallographic data. The crystal structure of these two complexes has revealed that the free ligand (L) is deprotonated twice at the oxygen and sulfur atoms and they are coordinated with the complexes through phenoxide-O, azomethine-N and thiolate-S atoms. The single-crystal X-ray structures of complex (1) exhibits a square planar structure, while complex (2) reveals trigonal bipyramidal distorted square based pyramidal structure. Anticancer activity of ligand and the complexes 1-2 are evaluated in human adenocarcinoma (MCF-7) cells. The preliminary bioassay indicates that the free ligand and the complexes 1-2 exhibit inhibitory activity against the human adenocarcinoma cancer cell lines.

Crystal structure of [1-(3-eth-oxy-2-oxido-benzyl-idene-κO (2))-4-phenyl-thio-semicarbazidato-κ(2) N (1),S](tri-phenylphosphane-κP)nickel(II).

In the title complex, [Ni(C16H15N3O2S)(C18H15P)], the Ni(II) atom has a distorted tetra-hedral coordination geometry, comprised of N, S, O and P atoms of the tridentate thiosemicarbazide ligand and the P atom of the triphenylphosphane ligand. The benzene ring makes a dihedral angle of 53.08 (11)° with the phenyl ring of the phenyl-thio-semicarbazide moiety and dihedral angles of 73.69 (11), 20.38 (11) and 71.30 (11)° with the phenyl rings of tri-phenyl-phosphane ligand. A pair of N-H⋯N hydrogen bonds generates an R 2 (2)(8) ring graph-set motif. The eth-oxy group is disordered over two positions, with site occupancies of 0.631 (9) and 0.369 (9). The mol-ecular structure is stabilized by a weak intra-molecular C-H⋯O hydrogen bond. In the crystal, weak N-H⋯N and C-H⋯π inter-actions connect the mol-ecules, forming a three-dimensional network.

N'-[(E)-3-Bromo-5-chloro-2-hy-droxy-benzyl-idene]furan-2-carbohydrazide.

In the title compound, C12H8BrClN2O3, the furan ring makes a dihedral angle of 17.2 (2)° with the six-membered ring. An intra-molecular O-H⋯N hydrogen bond stabilizes the mol-ecular conformation. In the crystal, N-H⋯O hydrogen bonds connect the mol-ecules into chains running along the c-axis direction. The crystal packing is additionally stabilized by C-H⋯O inter-actions into a three-dimensional supramolecular architecture.

Synthesis, characterization, structural analysis of metal(II) complexes of N'-[(E)-3-Bromo-5-Chloro-2-hydroxybenzidene]-4-hydroxybenzohydrazide-Multisubstituted Schiff base as a F(-) and Cu(2+) ions selective chemosensor.

New colorimetric chemosensor, N'-[(E)-3-Bromo-5-Chloro-2-hydroxybenzidene]-4-hydroxybenzohydrazide, containing OH and NH groups as binding sites have been synthesized and characterized by spectral UV, IR, NMR and ESR. The molecular structure of ligand is determined by X-ray crystallography and it has the monoclinic space group P21/c with cell parameters a=15.1058(6), b=14.3433(6), c=17.5800(8)Å and Z=8. The electronic spectral measurements show that Co(2+), Ni(2+) and Zn(2+) complexes have tetrahedral geometry, while Cu(2+) complex has square planar geometry. Magnetic measurements show that Cu(2+), Co(2+) and Ni(2+) complexes have paramagnetic behavior and Zn(2+) complex has diamagnetic behavior. Anion binding studies carried out using (1)H NMR and UV-visible spectrophotometric titrations revealed that these receptors exhibit selective recognition towards F(-) over other halide anions. The selectivity for F(-) among the halides is attributed mainly to the hydrogen-bond interaction of the receptor with F(-). Receptor (5 × 10(-5)M) shows color change from colorless to yellow in the presence of tetrabutylammonium fluoride (TBAF, 1.5 × 10(-3)M). Moreover, F(-)-induced color changes remain the same even in the presence of large excess of Cl(-), Br(-) and I(-). The binding constant is found to be higher towards F(-) ion and this may be due to presence of OH group, which offers extra binding site. Chromogenic receptor undergoes distinct color changes from colorless to green on gradual addition of Cu(2+) can be used as colorimetric probes for spectrophotometric and visual analysis of Cu(2+) in the presence of other transition metal ions such as Co(2+), Ni(2+) and Zn(2+).

Bio-approach: Ureolytic bacteria mediated synthesis of ZnO nanocrystals on cotton fabric and evaluation of their antibacterial properties.

ZnO nanoparticles (NPs) synthesis on cotton fabric through the formation of biologically activated ammonia from urea broth in the presence of the ureolytic bacterial species Serratia ureilytica (HM475278) has been described in the present contribution. The cotton fabric was immersed in biogenic zinc ammonium complex medium and subjected to heat treatment at an optimum temperature of 50 °C for different durations of time (30, 60, 90 min). The crystal growth of ZnO nanoparticles on cotton fabric was characterized by analytical techniques such as SEM-EDAX, XRD, TGA, CHNS and UV-visible spectra, and evaluation of antibacterial activity was carried out against Escherichia coli and Staphylococcus aureus. Crystal growth and morphological studies confirmed the attachment of ZnO NPs on the cotton fabric. Spherical to nanoflower shaped particles were obtained with increasing time duration from 30 to 90 min. The antibacterial activity of loaded cotton fabrics was found to be substantially higher than the bare cotton samples. Wet film interfacial contact studies have shown greater antibacterial activity as a result of nanoparticle contact at the bio-interface, as observed by Epi-fluorescent microscopic observations.

Synthesis and spectral characterization of Schiff base complexes of Cu(II), Co(II), Zn(II) and VO(IV) containing 4-(4-aminophenyl)morpholine derivatives: antimicrobial evaluation and anticancer studies.

Metal(II) chelates of Schiff bases derived from the condensation of 4-morpholinoaniline with substituted salicylaldehyde have been prepared and characterized by (1)H NMR, IR, electronic, EPR, and magnetic measurement studies. The complexes are of the type M(X-MPMP)2 [where M=Cu(II), Co(II)), Zn(II), or VO(IV); MPMP=2-[(4 morpholinophenyl imino) methyl] 4-X-phenol, X=Cl, (L1H), X=Br (L2H)]. Single crystal X-ray crystallography studies confirm the structure of newly synthesized Schiff bases. The Schiff bases act as bidentate monobasic ligands, coordinating through deprotonated phenolic oxygen and azomethine nitrogen atoms. The free ligands and metal complexes are screened for their biopotency. Metal complexes exhibit better activity than ligands. Anticancer activity of ligands and their metal complexes are evaluated in human heptocarcinoma(HepG2) cells. The preliminary bioassay indicates that the Schiff base and its zinc complex exhibit inhibitory activity against the human gastric cancer cell lines.

4-Chloro-2-[(2,6-diisopropyl-phen-yl)imino-meth-yl]phenol.

The asymmetric unit of the title compound, C(19)H(22)ClNO, contains two independent mol-ecules in which the dihedral angles between the aromatic rings are 76.45 (9) and 74.69 (9)°. An intra-molecular O-H⋯N hydrogen bond occurs in each mol-ecule. The crystal structure features weak C-H⋯π inter-actions.

(E)-4-Bromo-2-[(2,6-diisopropyl-phen-yl)imino-meth-yl]phenol.

In the title compound, C(19)H(22)BrNO, the dihedral angle between the benzene rings is 76.17 (14)° and an intra-molecular O-H⋯N hydrogen bond with an S(6) graph-set motif is present. One methyl group is disordered over two sets of sites with site occupancies of 0.66 (3) and 0.34 (3). A weak inter-molecular C-H⋯π inter-action is observed in the crystal structure.

2-[(2,6-Diisopropyl-phen-yl)imino-meth-yl]-4-iodo-phenol.

The asymmetric unit of title compound, C(19)H(22)INO, contains two independent mol-ecules. Classical intra-molecular O-H⋯N hydrogen bonds stabilize the mol-ecular structures. The crystal structure is stabilized by weak inter-molecular C-H⋯π and π-π [centroid-centroid = 3.8622 (18) Å] inter-actions. In both mol-ecules, the aromatic rings are nearly perpendicular to each other [dihedral angles = 84.26 (17) and 86.69 (15)°].

Bone disease in thyrotoxicosis.

Thyrotoxicosis, a clinical syndrome characterized by manifestations of excess thyroid hormone, is one of the commonly-recognised conditions of the thyroid gland. Thyrotoxicosis causes acceleration of bone remodelling and though it is one of the known risk factors for osteoporosis, the metabolic effects of thyroxine on bone are not well discussed. Studies show that thyroid hormones have effects on bone, both in vitro and in vivo. Treatment of thyrotoxicosis leads to reversal of bone loss and metabolic alterations, and decreases the fracture risk. There are limited studies in India as to whether these changes are fully reversible. In this review we discuss about the effects of thyrotoxicosis (endogenous and exogenous) on bone and mineral metabolism, effects of subclinical thyrotoxicosis on bone and mineral metabolism and effects of various forms of treatment in improving the bone mineral density in thyrotoxicosis.

Swyer syndrome: a case report with literature review.

Gonadoblastomas are known to develop in dysgenetic gonads, especially so, if Y chromosome material is present. A 20-years-old girl who noticed breast development since the age of 12 years presented with primary amenorhoea, distension of lower abdomen and intermittent pain for two months. She had breakthrough bleeding with six months of estrogen replacement. Tanner breast stage was five and pubic hair stage was also five. Examination revealed a mass in the lower abdomen extending into hypogastrium, umbilical and lumbar regions. Her gonadotropin levels were grossly elevated. Karyotyping showed 46XY. CT scan of abdomen showed a 17X11 cm mass in the pelvis without visible gonads. Surgical excision of the mass along with bilateral salpingophorectomy was performed. Histopathology revealed the mass to be a dysgerminoma, while the right gonad lodged gonadoblastoma. She was diagnosed as a rare case of Swyer syndrome.

High-density lipoprotein cholesterol: How High.

The high-density lipoprotein cholesterol (HDL-C) is considered anti-atherogenic good cholesterol. It is involved in reverse transport of lipids. Epidemiological studies have found inverse relationship of HDL-C and coronary heart disease (CHD) risk. When grouped according to HDL-C, subjects having HDL-C more than 60 mg/dL had lesser risk of CHD than those having HDL-C of 40-60 mg/dL, who in turn had lesser risk than those who had HDL-C less than 40 mg/dL. No upper limit for beneficial effect of HDL-C on CHD risk has been identified. The goals of treating patients with low HDL-C have not been firmly established. Though many drugs are known to improve HDL-C concentration, statins are proven to improve CHD risk and mortality. Cholesteryl ester transfer protein (CETP) is involved in metabolism of HDL-C and its inhibitors are actively being screened for clinical utility. However, final answer is still awaited on CETP-inhibitors.

N'-[(E)-2-Hy-droxy-3,5-diiodo-benzyl-idene]pyridine-3-carbohydrazide.

In the title compound, C(13)H(9)I(2)N(3)O(2), the dihedral angle between the two aromatic rings is 10.5 (2)°. The mol-ecule displays a trans configuration with respect to the C=N bond. An intra-molecular O-H⋯N hydrogen bond occurs. The crystal packing is stabilized by N-H⋯O and C-H⋯O hydrogen bonds.

N'-[(1E)-4-Diethyl-amino-2-hy-droxy-benz-idene]benzohydrazide.

In the title compound, C(18)H(21)N(3)O(2), the dihedral angle between the phenyl and benzene rings is 36.85 (10)°. The methyl C atom of one of the ethyl groups is disordered over two positions with site occupancies of 0.810 (8) and 0.190 (8). The mol-ecular structure is stabilized by a classical intra-molecular O-H⋯N hydrogen bond. The crystal structure exhibits weak inter-molecular N-H⋯O, C-H⋯O and C-H⋯π inter-actions.

4-[(E)-(4-Diethyl-amino-2-hy-droxy-benzyl-idene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one.

In the title compound, C(22)H(26)N(4)O(2), the phenyl ring and hy-droxy-benzene group are twisted with respect to the central pyrazolone ring, making dihedral angles of 54.05 (5) and 21.80 (6)°, respectively. One of the ethyl groups is disordered over two positions with site occupancies of 0.872 (6) and 0.128 (6). The mol-ecular structure features short intra-molecular O-H⋯N and C-H⋯O contacts. The crystal packing exhibits weak inter-molecular C-H⋯O and C-H⋯π inter-actions.

N'-[(E)-2-Hy-droxy-3,5-diiodo-benzyl-idene]cyclo-hexa-ne-1-carbohydrazide.

In the title compound, C(14)H(10)I(2)N(2)O(2), the two aromatic rings are inclined at a dihedral angle of 16.72 (33)°. The mol-ecular structure is stabilized by an intra-molecular O-H⋯N hydrogen bond. In the crystal, inter-molecular N-H⋯O inter-actions link the mol-ecules into chains running along the c axis. C-H⋯O inter-actions also occur. The crystal used for the structure determination was a non-merohedral twin with a domain ratio of 0.972 (2):0.028 (2).

2,4-Diiodo-6-{[4-(morpholin-4-yl)phenyl]iminomethyl}phenol.

In the title compound, C(17)H(16)I(2)N(2)O(2), the two aromatic rings are almost coplanar [dihedral angle 2.57 (15)°]. The morpholine ring adopts a chair conformation. The mol-ecular structure is stabilized by an O-H⋯N hydrogen bond and the crystal packing exhibits weak inter-molecular C-H⋯O and π-π [centroid-to-centroid distances 3.663 (3)-4.073 (3) Å] inter-actions.