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A series of bridging linkers such as pyrazine (L1), 4,4′-bipyridine (L2), (E)-1,2-di(pyridin-4-yl)ethene (L3), 1,2-di(pyridin-4-yl)ethane (L4), 1,2-di(pyridin-4-yl)disulfane (L5), 1,2-di(pyridin-4-yl)diazene (L6) and 1,4-di(pyridin-4-yl)benzene (L7) has been used in a Cu(II)-mediated cyano group activation in sodium 2-(2-(dicyanomethylene)hydrazineyl)benzenesulfonate (NaHL), leading to [{Cu(H2O)(La)}2(μ-L1)]n (1) (La = (Z)-2-(1-cyano-2-imino-2-methoxyethylidene)-1-(2-sulfonatophenyl)hydrazin-1-ide), [{Cu(H2O)(La)}2(μ-L2)]·2H2O (2), [{Cu(X)(La)}2(μ-L3)]·3H2O (3) (X = H2O or CH3OH for the two independent units), [{Cu(CH3OH)(La)}2(μ-L4)]·2H2O (4), [{Cu(La)}2(μ-L5)2]n (5), [{Cu(μ-La)}2(μ-L6)Cu(H2O)(La)]2·4H2O (6) and [{Cu(H2O)(La)}2(μ-L7)] (7), respectively. Depending on the length of the respective linkers, the distance between the two copper(II) centres in 1–7 can be expanded/adjusted from 6.762 to 15.138 Å. The catalytic activity of the synthesized compounds in the cyanosilylation reaction of aldehydes with trimethylsilyl cyanide in methanol was performed. No linear correlation among the length of the bridging ligands and the yield of 2-phenyl-2-((trimethylsilyl)oxy)acetonitrile was observed in 1–7 catalysed cyanosilylation of benzaldehyde with trimethylsilyl cyanide, but the copper complexes show a higher catalytic activity in comparison to the monomer [Cu(H2O)2(La)]. The higher catalytic activity exhibited by complex 5 was further investigated evaluating the effects of reaction time, catalyst amount, temperature and the activity with different aldehydes. [ABSTRACT FROM AUTHOR]

This study investigates the real consequences of classification shifting by examining its effect on corporate investment efficiency. The underlying expectation is that the ways of reporting different profit items within the income statement should increase information asymmetry between managers and capital providers regarding the level of core and, so, more likely repeatable firm performance. We anticipate that classification shifting will aggravate agency problems and distort managers' own perceptions of their firms' sustainable profitability, resulting in imperfect investment-related information sets for them, ultimately leading to inefficient investing. We find that classification shifting strongly and significantly decreases the responsiveness of investment to growth opportunities and is, thus, associated with less efficient investing. After investigating the economic mechanisms explaining this association, our results are more pronounced when other information and agency problem-related factors that should protect against inefficient investing are weaker, and also for firms whose managers have fewer opportunities to learn from peers, which could alleviate potential classification shifting-related distortion effects on managerial perceptions. Our study provides evidence on the adverse real consequences of classification shifting, a form of earnings management without any reversing effects for bottom-line future performance, with reference to a very important firm-level outcome; namely, efficient investing. [ABSTRACT FROM AUTHOR]

Herein, we have isolated new 20-membered macrocycles by the simple condensation of α,α-dihalo-β-oxoaldehydes with diaminofurazan in acetonitrile. The interior and exterior sites of these macrocycles comprise hydrogen and halogen bond donor sites, respectively. Depending on the electron donating or accepting character of the substituents at the exterior sites of macrocyclic scaffolds, the average cavity diameters range from 8.15 to 8.47 Å. [ABSTRACT FROM AUTHOR]

Two tetranuclear and two mononuclear Cu(II) complexes with arylhydrazones of malononitrile derived ligands (compounds 1–2 and 3–4, respectively), one trinuclear Co(II/III) complex with an arylhydrazone of acetoacetanilide (5) and one tetranuclear Zn(II) complex of 3-(2-carboxyphenyl-hydrazone)pentane-2,4-dione (6) were screened as potential catalysts in the peroxidative oxidation of cyclohexane by aqueous H2O2 in acetonitrile. The best results were attained in the presence of pyrazine-2-carboxylic acid (PCA) with 1 (26% yield, TON = 52.0) and with 2 (24%, TON = 48.0) after 4 h at 40 °C. In the presence of complexes 5 and 6, no oxygenated products were detected in the studied conditions. The employment of non-conventional conditions like supercritical carbon dioxide (scCO2) as reaction medium or microwave (MW) irradiation was assessed for complexes 1 and 2. After 6 h in acetonitrile–scCO2, at 50 °C and with HNO3 as promoter, only 17% yield was achieved using 1 as catalyst, and 21% using 2. Total yields of oxygenates up to 14 (with 1) and 13% (2) and TOFs of 56.0 and 52.0 h−1, respectively, were obtained working under MW irradiation at 70 °C and for the much shorter time of 0.5 h.

Synopsis The research problem This study examined the effect of having debt contracts that contain balance sheet covenants on the decision to make seasoned equity offerings (SEOs). Motivation Prior studies examined the determinants of equity issuance without considering private debt contracts that contain balance sheet covenants. Generally, firms are not restricted from stock issuance when they have financial debt covenants. This might motivate firms to make SEOs when they are more susceptible to balance sheet debt covenant violations. Making SEOs increases firms' equity capitals in the short term and, therefore, has the direct effect of improving balance sheet covenants in the current period. This effect motivated this study to examine whether firms are more likely to conduct SEOs when their debt contracts include more-restrictive balance sheet covenants. The test hypothesis The hypothesis of the study is in the null form, which states that balance sheet covenant restrictiveness is unrelated to the probability of conducting SEOs. Target population The target population includes shareholders, debtholders, and firm managers. Adopted methodology Panel data estimation was used, specifically, the fixed effects model. Analyses The empirical analysis was conducted on a unique sample of UK listed firms with private debt covenants that is hand-collected from annual reports. Equity issuance in the sample is based on private placements, which are a common type of SEO in the UK. The restrictiveness of balance sheet-based covenants is defined as the number of balance sheet covenants in a loan contract or the tightness of net worth covenant slack. Findings The results show that balance sheet covenant restrictiveness is positively associated with the probability of conducting SEOs through private placements. The baseline result is robust to the application of a number of the controls often used in the literature, including cash shortage, the use of balance sheet covenants in the previous loan contract, earnings management, and the quality of external governance. It is also robust to excluding the financial crisis period and addressing potential endogeneity concerns using a propensity score-matching procedure. Additionally, further analysis provides some evidence that equity issuance by firms with more-restrictive balance sheet covenants is negatively associated with future operating performance, suggesting that these firms may not efficiently use the raised capital. [ABSTRACT FROM AUTHOR]

Arylhydrazones of active methylene compounds (AHAMCs) are potent chemotherapy agents for the cancer treatment. AHAMCs enhance the apoptotic cell death and antiproliferation properties in cancer cells. In this study, a series of AHAMCs, 13 compounds, was assayed for cytotoxicity, apoptosis, externalization of phosphatidylserine, heterogeneity and cellular calcium level changes. The in vitro cytotoxicity study against HEK293T cells suggests that AHAMCs have significant cytotoxic effect over the concentrations. Top 5 compounds, 5-(2-(2-hydroxyphenyl) hydrazono)pyrimidine-2,4,6(1H,3H,5H)-trione (5), 4-hydroxy-5-(2-(2,4,6-trioxo-tetrahydro-pyrimidin-5(6H) ylidene)hydrazinyl)benzene-1,3-disulfonic acid (6), 5-chloro-3-(2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl)-2-hydroxybenzenesulfonic acid (8), 5-(2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl)-4-hydroxybenzene-1,3-disulfonic acid (9) and 2-(2-sulfophenylhydrazo)malononitrile (10) were chosen for the pharmacodynamics study. Among these, compound 5 exhibited the better cytotoxic effect with the IC50 of 50.86 ± 2.5 mM. DNA cleavage study revealed that 5 induces cell death through apoptosis and shows more effects after 24 and/or 48 h. Independent validation of apoptosis by following the externalization of phosphatidylserine using Annexin-V is also in agreement with the potential activity of 5. Single cell image analysis of Annexin-V bound cells confirms the presence of mixture of early, mid and late apoptotic cells in the population of the cells treated with 5 and a decreased trend in cell-to-cell variation over the phase was also identified. Additionally, intracellular calcium level measurements identified the Ca2+ up-regulation in compound treated cells. A brief inspection of the effect of the compound 5 against multiple human brain astrocytoma cells showed a better cell growth inhibitory effect at micro molar level. These systematic studies provide insights in the development of novel AHAMACs compounds as potential cell growth inhibitors for cancer treatment.