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Three bimetallic triangles were constructed via a step-wise assembly of tailored terpyridine building blocks. Oligomeric trimer 2 was obtained by reacting ligand 1 with Ru(II). Subsequent cyclization of trimer 2 with Zn(II), Cd(II), and Fe(II) resulted in the formation of bimetallic triangles 3, 4, and 5 in high yield, respectively. All triangles were characterized by NMR spectroscopy, ESI and travelling-wave ion mobility-mass spectrometry (MS), as well as gradient MS, which provided insight into their stabilities.

The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)RuII(ACN)3, utilizing designed terpyridines possessing electron-donating and -withdrawing aromatic residues for tuning the catalytic activity of the Ru(II) complex. These complexes displayed excellent catalytic activity for several oxidative organic transformations including late-stage C-H functionalization of aldehydes with NH2OR to valuable primary amides in nonconventional aqueous media with excellent yield. Its diverse catalytic power was established for direct oxo-scissoring of a wide range of alkenes to furnish aldehydes and/or ketones in high yield using a low catalyst loading in the water. Its smart catalytic activity under mild conditions was validated for dioxygenation of alkynes to highly demanding labile synthons, 1,2-diketones, and/or acids. This general and sustainable catalysis was successfully employed on sugar-based substrates to obtain the chiral amides, aldehydes, and labile 1,2-diketones. The catalyst is recovered and reused with a moderate turnover. The proposed mechanistic pathway is supported by isolation of the intermediates and their characterization. This multifaceted sustainable catalysis is a unique tool, especially for late-stage functionalization, to furnish the targeted compounds through frequently used amidation and oxygenation processes in the academia and industry.

Planar, terpyridine-based metal complexes with the Sierpinski triangular motif and alkylated corners undergo a second self-assembly event to give megastructural Sierpinski pyramids; assembly is driven by the facile lipophilic-lipophilic association of the alkyl moieties and complementary perfect fit of the triangular building blocks. Confirmation of the 3D, pyramidal structures was verified and supported by a combination of TEM, AFM, and multiscale simulation techniques.

Mankind has been fighting diseases since the inception of civilization. With the discovery of molecules that are known as “drugs” now, the field of synthetic chemistry to prepare these molecules became extremely important. From paracetamol to vancomycin, scientists have synthesized drugs with increasing complexity over the past two decades. However, with the turn of century, there has been a paradigm shift toward developing green and sustainable strategies for drug synthesis. In 2015, United Nations put forward a framework for a new sustainability-focused development plan entitled “Transforming Our World: The 2030 Agenda for Sustainable Development.” The guideline consists of 17 sustainable development goals which encompass a broad range of topics, primarily recognizing the need for green and sustainable chemistry and engineering. Successful implementation of this plan is extremely crucial for the future of our planet as well as all living organisms including human. Green yet sustainable methodologies are being developed and established through judicious choice of starting materials, atom economic methodologies involving minimum number of chemical steps, convenient use of greener solvents and reagents, and efficient strategies for product isolation and purification. The scope of this chapter includes but not limited to different avenues (e.g., use of green solvents, atom economical and catalytic transformations, etc.) that have been undertaken to develop green methodologies for synthesizing existing as well as new drugs. The chapter will primarily focus on synthetic methodologies aimed toward green synthesis for drugs of tropical diseases such as malaria and HIV.

Objectives The present study aimed to evaluate the role of hyperlipidemia in increased formation of advanced lipoxidation end products (ALEs) and to evaluate whether there is any relationship between ALEs generation and erythrocyte glucose-6-phosphate dehydrogenase (G6PD) activity in cases of mild nonproliferative diabetic retinopathy (MNPDR). Methods In this study, we enrolled 100 patients with type 2 diabetes and MNPDR, 100 subjects with type 2 diabetes but without retinopathy (DNR) and 90 normal individuals without diabetes as healthy controls (HCs). Erythrocyte nicotinamide dinucleotide phosphate (NADPH), G6PD activity, serum total cholesterol, low- and high-density lipoprotein (LDL, HDL) and triglyceride levels were determined by photometric assay. Serum malondialdehyde (MDA) protein adduct and hexanoyl-lysine (HEL) were measured by an enzyme-linked immunosorbent assay (ELISA). Results A robust linear relationship was observed between MDA protein adduct and LDL or cholesterol or triglyceride levels, and HEL and LDL or cholesterol or triglyceride levels in subjects with MNPDR (p=0.0001). A significant inverse association was observed between erythrocyte G6PD activity and serum MDA protein adductor HEL levels in subjects with MNPDR (p=0.0001). Conclusions Hyperlipidemia is an important factor that is associated with increased ALEs formation in persons with MNPDR. Increased ALEs generation was associated with decreased G6PD activity and low NADPH levels in cases of MNPDR, suggesting their detrimental role in the occurrence of early NPDR.

The synthetic chemists always look for developing new catalysts, sustainable catalysis, and their applications in various organic transformations. Herein, we report a new class of water-soluble complexes, (Ar-tpy)Ru

The design and construction of a novel terpyridine-based, dimetallic, 2D [4]triangulane architecture are reported. Synthesis of the metallotriangulane is achieved by multicomponent stepwise assembly of six bidentate and three tetradentate monomers. Characterization was accomplished by NMR spectroscopy, mass spectrometry and TEM microscopy.

The one-step synthesis of the first homoleptic metallomacrocycle is reported. Characterization of the OsII complex, along with its FeII and RuII analogues, was accomplished by NMR spectroscopy, ESI-MS, TWIM-MS, gradient tandem-MS, CV, luminescence and UV/Vis spectroscopy. Center-of-mass collision energies, derived from gradient tandem-MS, reveal that the -based structures are more stable than those of .

Interstitial-free (IF) and dual-phase (DP) steel sheets of 1-mm thickness were joined by friction stir spot welding with a convex shoulder tool. Two different combinations were used; one with IF as top sheet (IF/DP) and another with DP as top sheet (DP/IF). Material intermixing between the overlapping sheets takes place within the stirred zone. The truncated sheet interface curls upward into the top sheet, more so in case of IF/DP, due to lower resistance offered by the top (IF) sheet to the upward migrating bottom (DP) sheet material. Material from the IF steel contains ferrite phases, while that from the DP steel contains acicular ferrite and lath martensite. Under quasi-static loading, the crack passes along the dissimilar interface and into the top sheet thickness, resulting in pull-out failure. Under cyclic loading, the failure is brought about by the initiation of kinked fatigue cracks and their subsequent propagation through the top and bottom sheet thickness. The dominant fatigue crack moves through the reduced top sheet thickness. The mechanical performance of DP/IF is better than IF/DP owing to higher strength of the stirred zone. The mechanical performances of the dissimilar joints are intermediate to that of the similar material joints.

The present study was aimed to investigate the relation between nuclear factor kappa beta (NFκB) activation and downstream up-regulation of vascular endothelial growth factor (VEGF) in diabetic retinopathy (DR). Moreover the study was intended to evaluate the role of VEGF gene single nucleotide polymorphisms (SNPs) in DR occurrence and to investigate the functional relevance of VEGF gene SNPs in terms of VEGF expression in DR. Serum level of VEGF, VEGF R1 (receptor 1), VEGF R 2 (receptor 2) and NFκB (p50/65) activity was measured by enzyme linked immune sorbent assay. Genotyping and allelic composition of different SNPs i.e., rs2010963, rs3025039, rs1570360 and rs 2071559 were investigated by Taqman SNP genotyping assay. VEGF, NFκB p50/p65, and VEGF R1 & R2 gene expressions were quantified by real time quantitative polymerase chain reaction. Increased NFκB p50/p65 activity and expressions were observed in non proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR) subjects compared to type 2 diabetes mellitus without retinopathy (DNR) group. Significantly elevated levels of serum VEGF and highest VEGF expression were found among PDR subjects compared to DNR or NPDR subjects. CC genotype and C allele of rs2010963 and TT genotype and T allele of rs3025039 were significantly over represented among PDR subjects compared to DNR group. Increased activation of NFκβ in NPDR and PDR subjects might involve increased up regulation of VEGF. VEGF SNPs i.e., rs2010963 C allele and rs3025039 T allele might be associated with PDR occurrence and in turn regulates VEGF expression among PDR subjects.

A novel terpyridine-based architecture that mimics a first-generation Sierpinski triangle has been synthesized by multicomponent assembly and features tpy-Cd(II)-tpy connectivity (tpy=terpyridine). The key terpyridine ligands were synthesized by the Suzuki cross-coupling reaction. Mixing two different terpyridine-based ligands and Cd(II) in a precise stoichiometric ratio (1:1:3) produced the desired fractal architecture in near-quantitative yield. Characterization was accomplished by NMR spectroscopy, mass spectrometry, and transmission electron microscopy.

The design and construction of the first multicomponent stepwise assembly of atpy-Ru(II) -tpy-based (tpy=terpyridine), three-dimensional, propeller-shaped trismacrocycle, 8, are reported. Key steps in the synthesis involve the preparation of a hexaterpyridinyl triptycene and its reaction with dimeric, 60°-directional, bisterpyridine-Ru(II) building blocks. Characterization includes ESI- and ESI-TWIM-MS and TEM, along with 1D and 2D (1) H NMR spectroscopy.

Introduction Although TSH measurement by electrochemiluminescence immunoassay has become commonplace in India, significant discrepancy has been observed on interpretation of the test results when the manufacturer supplied biological reference interval (BRI) criteria were applied. This report determined whether the manufacturer's BRI (Roche Cobas) is transferable to the Indian population. Methods Three hundred seventy-eight age- and sex-matched healthy subjects were selected from an urban Indian population. TSH reference measurements were acquired, and the reference data were statistically analysed. Results BRI of the Indian urban reference population was determined by non-parametric means. BRI was found to be 1.134 to 7.280 μIU/ml. Conclusion BRI thus calculated was found to be significantly different from that mentioned by the manufacturer (0.27 to 4.20 μIU/ml), which, needless to mention, has profound clinical implications in this part of the globe.

Although 3rd generation TSH assays are the most widely used immunoassays, credible comparison studies, specially involving Indian sub-populations are practically non-existent. To compare the TSH measurements between chemiluminescence (Architect) and electrochemiluminescence (Cobas) inmmunoassays in an urban ambulatory Indian population. 1,615 subjects were selected randomly from the usual laboratory workflow, their TSH measured in Architect and Cobas and the paired data thus generated were statistically analysed. TSH values of Cobas were observed to be higher than the Architect values by 28.7 %, with a significant proportional difference between the two, but majority of the Cobas values (above 90 %) were within the limits of agreement with Architect values. In situations where both the instruments are in use simultaneously, a standardization of the methods is imperative, in larger interest of the patient populace.

The surface of Cloisite 30 B clay was treated with bromopropionyl bromide to form the clay Br-ended initiator needed for surface-initiated atom transfer radical polymerization (SI-ATRP). Several homo- and co-(SI-ATRP) polymerizations were conducted on the cured surface of the Cloisite 30 B clay using vinyl monomers, such as methyl methacrylate, styrene (St), and 2-(dimethylaminoethyl) methacrylate, along with the ligands 2,2′-bipyridine (bpy) and 1,1,4,7,10,10-hexamethyltriethylene tetraamine, and CuBr, as a catalyst. These grafted polymer–clay nanocomposites were characterized by X-ray diffraction, Thermal gravimetric analysis, differential scanning calorimetry, and Transmission electron microscopy. Most of the prepared nanocomposites displayed semi-exfoliated to exfoliated structures.

Background: The validity of the entire renal function tests as a diagnostic tool depends substantially on the Biological Reference Interval (BRI) of urea. Establishment of BRI of urea is difficult partly because exclusion criteria for selection of reference data are quite rigid and partly due to the compartmentalization considerations regarding age and sex of the reference individuals. Moreover, construction of Biological Reference Curve (BRC) of urea is imperative to highlight the partitioning requirements. Materials and Methods: This a priori study examines the data collected by measuring serum urea of 3202 age and sex matched individuals, aged between 1 and 80 years, by a kinetic UV Urease/GLDH method on a Roche Cobas 6000 auto-analyzer. Results: Mann-Whitney U test of the reference data confirmed the partitioning requirement by both age and sex. Further statistical analysis revealed the incompatibility of the data for a proposed parametric model. Hence the data was non-parametrically analysed. BRI was found to be identical for both sexes till the 2nd decade, and the BRI for males increased progressively 6th decade onwards. Four non-parametric models were postulated for construction of BRC: Gaussian kernel, double kernel, local mean and local constant, of which the last one generated the best-fitting curves. Conclusion: Clinical decision making should become easier and diagnostic implications of renal function tests should become more meaningful if this BRI is followed and the BRC is used as a desktop tool in conjunction with similar data for serum creatinine.

Mixing of metallocyclic trimers and tetramers in an exact 1 : 1.5 stoichiometry provided new supramolecular triangles in quantitative yields. Characterization of the new hetero-nuclear metallomacrocycles was achieved by (1)H, 2D-COSY, 2D-NOESY, and (13)C NMR spectroscopy, along with ESI and TWIM mass spectrometry. Gradient tandem MS (gMS(2)) provided insight into the stabilities of the binuclear structures.

Several dendrimer–clay nanocomposites have been prepared. Firstly, the dendrimer (DE1)/clay nanocomposite was obtained via an in situ free radical polymerization of a double bond-ended dendrimer (DE1), derived from Behera's amine by using 2,2′-azobisisobutyronitrile (AIBN), as initiator, and Cloisite 30 B, as nanofiller. Further free radical in situ copolymerization processes were conducted between DE1, methyl methacrylate (MMA), and styrene (St). Two other dendrimer/clay nanocomposites were prepared by the reaction of second generation (G2)–36-acid dendrimer (DE2) and N,N′,N′,N′-tetrakis[2-hydroxy-1,1-bis(hydroxylmethyl) ethyl]-α,α,ω,ω-alkane-tetracarboxamide [6]-10-[6] Arborols (DE3) with montmorillonite clay (MMT). POLYM. ENG. SCI., 53:2166–2174, 2013. © 2013 Society of Plastics Engineers

Average case complexity, in order to be a useful and reliable measure, has to be robust. The probability distribution, generally uniform, over which expectation is taken should be realistic over the problem domain. But algorithm books do not certify that the uniform inputs are always realistic. Do the results hold even for non uniform inputs? In this context we observe that Binary Tree sort is more robust than the fastand popular Quick sort in the average case. &nbsp

Synthesis of terpyridine-based building blocks has allowed the self-assembly of a nanosized metallomacrocycle with precisely positioned, peripheral metal complexes. Construction of the precursors included the assembly of a heteroleptic bisterpyridine-Ru(II) complex possessing a diiodoaryl moiety that was subsequently reacted with two equivalents of 4′-ethynyl-2,2′ : 6′,2′′-terpyridine via a Pd(0)-catalyzed Sonagashira coupling, to generate the requisite monomer with two, 120°-juxtaposed metal coordination sites. Addition of one equivalent of Fe(II) to one equivalent of the bisligand afforded the metallocycle with 12 metals [6 internal Fe(II) ions and 6 external Ru(II) ions] measuring ca. 7 nm in diameter.

High concentrations of silica in rocks are determined by means of the stable α-12-molybdosilicic acid formed at around pH 4.2 in acetate buffer. Phosphate interference is avoided by acidification with sulphuric acid. Silica is quantified by differential spectrophotometry at 400 nm against standard rock solutions. Considerable amounts of phosphorus, arsenic and titanium and small amounts of germanium and vanadium do not interfere. The standard deviation is about 0.3%. The method is rapid and suitable for routine analysis of silicate and phosphate rocks.