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A palladium-catalyzed one-pot stepwise coupling-annulation reaction of 2-chloroqunoline-3-carbonitriles enabled the direct synthesis of sulfur-substituted benzo[b][1,6]naphthyridines via multiple bond formation. The reaction provided an unusual mode for cyclization as sodium sulfide, a soft nucleophile, preferred to attack on the carbon of the nitrile group rather than on the C-C triple bond. The developed chemistry was extended with the secondary amines as nucleophiles to afford nitrogen-substituted benzo[b][1,6]naphythyridines while primary amines afforded hydroamination products . The hydromination products were transformed to benzo[b][1,6]naphthyridones via a base-mediated cyclization reaction. The  developed protocol features inexpensive and easily synthesizable starting materials, easy operations, and a high efficiency and tolerance to a broad range of substrates.

In this study, we demonstrated that the cytotoxicity of the protoberberine alkaloids such as coralyne, berberine and jatrorrhizine to several human cancer cell lines can be improved significantly in combination with UVA exposure. However, the phototoxic property of coralyne was much higher than that of the other two alkaloids. The combination of coralyne and UVA (designated as CUVA) induced oxygen-independent cytotoxicity in the human lung cancer A549 cells by producing more lethal DNA double-strand breaks, and the effect was mediated via the replication machinery. In comparison, the berberine-induced phototoxicity to the A549 cells was mediated by reactive oxygen species generation, mitochondrial membrane permeabilisation and caspase-9/caspase-3 activation.

The current study summarizes a unique green process for the synthesis of silver nanoparticles (AgNPs) by simple treatment of silver nitrate with aqueous extract of Ammania baccifera. Phytosynthesized AgNPs were characterized by various advanced analytical methods and studied for its use against infections associated with burns. Formation of AgNPs was observed by visual color change from colorless to dark brown and confirmed by UV-visible characteristic peak at 436 nm. Zeta potential, particle size and polydispersity index of nano-silver were found to be -33.1 ± 1.12, 112.6 ± 6.8 nm and 0.3 ± 0.06 respectively. XRD spectra revealed crystalline nature of AgNPs whereas TEM confirmed the presence of mixed morphology of AgNPs. The overall approach designated in the present research investigation for the synthesis of AgNPs is based on all 12 principles of green chemistry, in which no man-made chemical other than the silver nitrate was used. Synthesized nano-silver colloidal dispersion was initially tested for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against a panel of organisms involved in infections associated with burns (Pseudomonas aeruginosa (PA), Staphylococcus aureus (SA) and methicillin resistant S. aureus (MRSA)). MIC and MBC were found to be in range of 0.992 to 7.93 and 7.93 to 31.75 μg/mL respectively. MBC was used for formulation of AgNP gel and tested for its efficacy using agar well diffusion method against PA, SA and MRSA. Comparative bactericidal efficacy of formulated gel (0.03% w/w) and marked formulation Silverex™ ionic (silver nitrate gel 0.2% w/w) showed equal zone of inhibition against all pathogenic bacteria. Formulated AgNP gel consisting of 95% lesser concentration of silver compared to marketed formulation was found to be equally effective against all organisms. Hence, the formulated AgNP gel could serve as a better alternative with least toxicity towards the treatment presently available for infections in burns., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Chronic obstructive pulmonary disease (COPD) is the most extensively studied and researched disease in pulmonology and a cause of significant morbidity, mortality, and financial burden on patient's family and country's economy. Its management continues to be a challenge to both the physician and the patient's family. So far, it is preventable and treatable but not curable. Emphysema, a phenotype of COPD, is the most debilitating condition associated with progressive exercise intolerance and severe dyspnea. Despite decades of research, medical treatments available so far have helped improve quality of life and slowed down the decline in respiratory function but did not significantly improve the survival benefits. Though surgical lung volume reduction (LVR) procedures have shown some promise in context to functional gains and survival but, only in a carefully selected group of patients, bronchoscopic LVR procedures are yet to explore their full potential and limitations. This paper retrospectively studied the developments so far, medical and surgical, with special emphasis on the bronchoscopic procedures of lung volume reduction, and tried to comparatively analyze the risks and benefits of each one of them through various trials and studies done to date.

Objectives: Pregabalin and clonidine have anti-nociceptive properties. This study assesses their efficacy in prolonging the analgesic effect of spinal anesthesia and post-operative analgesic requirement in patients undergoing vaginal hysterectomy., Materials and Methods: A total of 90 females in the age group of 30-60 years were randomly allocated in to three groups of 30 each, to receive either oral clonidine (150 μg) or oral pregabalin (150 mg) or oral multivitamin as placebo 1.5 h before spinal anesthesia with 3ml (15 mg) of 0.5% hyperbaric bupivacaine. Intensity of pain was measured on a visual analog scale (VAS) at the end of operation (0 h) then at 1,2,4,6,12 and 24 h thereafter. Diclofenac sodium intramuscularly 1 mg/kg was provided when the VASscore was >4 in the study period. Sedation was defined by Ramsay sedation scale at 0,6,12 and 24 h. Side-effects such as nausea and vomiting, respiratory depression and dryness of mouth were noted., Results: The VAS scores were significantly less in the pregabalin group compared with the clonidine group at 6,12 and 24 h post-operatively with a P < 0.0001. More sedation was seen in the clonidine group than in the pregabalin group (P < 0.05). Analgesic consumption and VAS scores were lower in clonidine and pregabalin group compared with the placebo group (P < 0.05)., Conclusion: Oral pregabalin (150 mg) prolongs the post-operative pain relief after spinal anesthesia but produces less sedation compared with oral clonidine (150 μg).

Purpose: To develop and validate specific and accurate UV spectrophotometric method of cefpodoxime proxetil by using different hydrotropic solubilizing agents., Materials and Methods: The present study deals with spectrophotometric analysis of cefpodoxime proxetil by utilizing 4 different hydrotropic agents such as ammonium acetate (6 M), sodium citrate (1.25 M), sodium gycinate (1 M), sodium chloride (1 M), and urea (1 M)., Results: From different hydrotropic agents, urea showed best aqueous solubility of cefpodoxime proxetil. The linearity was observed in the concentration range of 10-120 μg/ml. The method was validated and found to be precise. Accuracy (percent recovery) for cefpodoxime proxetil was found to be 99.82 ± 0.106., Conclusion: Urea as hydrotropic agent showed best aqueous solubility of cefpodoxime proxetil, which can be used as solubilizing agent. The proposed method is new, simple, safe, eco-friendly, economic, accurate, and cost-effective and can be successfully employed in routine analysis.

The diamagnetic dioxomolybdenum(VI) complex [(MoO(2))(2)(CH(2)L)(H(2)O)(2)]H(2)O (1) has been isolated in solid state from reaction of MoO(2)(acac)(2) with bis(2-hydroxy-1-naphthaldehyde)malonoyldihydrazone (CH(2)LH(4)) in 3:1 molar ratio in ethanol at higher temperature. The reaction of the complex (1) with electron donor bases gives diamagnetic molybdenum(VI) complexes having composition [Mo(2)O(5)(CH(2)LH(2))].2A.2H(2)O (where A=pyridine (py, 2), 2-picoline (2-pic, 3), 3-picoline (3-pic, 4), 4-picoline (4-pic, 5)). Further, when the complex (1) is allowed to react with protonic bases such as isonicotinoylhydrazine (inhH(3)) and salicyloylhydrazine (slhH(3)), reduction of molybdenum(VI) centre occurs leading to isolation of homobimetallic molybdenum(V) complexes [Mo(2)(CH(2)L)(inh)(2)(H(2)O)(2)] (6) and [Mo(2)(CH(2)L)(slh)(2)] (7), respectively. The composition of the complexes has been established by analytical, thermo-analytical and molecular weight data. The structure of the molybdenum(VI) complexes (1)-(5) has been established by electronic, IR, (1)H NMR and (13)C NMR spectral studies while those of the complexes (6) and (7) by magnetic moment, electronic, IR and EPR spectral studies. The dihydrazone is coordinated to the metal centres in staggered configuration in complex (1) while in anti-cis configuration in complexes (2)-(7). The complexes (6) and (7) possess magnetic moment of 2.95 and 3.06 BM, respectively, indicating presence of two magnetic centre in the complexes per molecule each with one unpaired electron on each metal centre without any metal-metal interaction. The electronic spectra of the complexes are dominated by strong charge transfer bands. All of the complexes involve six coordinated molybdenum centre with octahedral arrangement of donor atoms except in the complex (6), in which the molybdenum centre has rhombic arrangement of ligand donor atoms. The probable mechanism for generation of oxo-group in the complexes (2)-(5) involving coordinated water molecule has been proposed., (Copyright 2009. Published by Elsevier B.V.)