Higher carbene homologues: Naphtho[2,3-d]-1,3,2λ2-diazagermole, -diazastannole,and attempted reduction of 2,2-dichloronaphtho[2,3-d]-1,3,2-diazasilole

N,N′-Dineopentyl-2,3-diaminonaph-thalene 1, obtained by reaction of 2,3-diaminonaph-thalene with pivaloyl chloride and subsequent re-duction, was dilithiated and cyclodisubstituted with SiCl₄ to give dichloro-dineopentyl-naphtho[2,3-d]-1,3,2-diazasilole 2. Treatment of 2 with two equivalents of potassium in THF caused cleavage of the Si–N ring. A silylene could not be detected. The corresponding cyclic diaminogermylene 3 and diamino-stannylene 4 were obtained by direct ring closure of 1–Li₂ with GeCl₂·dioxane or SnCl₂, respectively. The compounds are structurally characterized by NMR and MS. The properties of 3 and 4 are compared with those of related germylenes and stannylenes. © 1998 John Wiley & Sons, Inc. Heteroatom Chem 9:439–444, 1998     

Origanum vulgare ssp. hirtum (Lamiaceae) Essential Oil Prevents Behavioral and Oxidative Stress Changes in the Scopolamine Zebrafish Model

Origanum vulgare ssp. hirtum has been used as medicinal herbs promoting antioxidant, anti-inflammatory, antimicrobial, and neuroprotective activities. We investigated the protective effects and the mechanism of O. vulgare ssp. hirtum essential oil (OEO) on cognitive impairment and brain oxidative stress in a scopolamine (Sco)-induced zebrafish (Danio rerio) model of cognitive impairment. Our results show that exposure to Sco (100 µM) leads to anxiety, spatial memory, and response to novelty dysfunctions, whereas the administration of OEO (25, 150, and 300 µL/L, once daily for 13 days) reduced anxiety-like behavior and improved cognitive ability, which was confirmed by behavioral tests, such as the novel tank-diving test (NTT), Y-maze test, and novel object recognition test (NOR) in zebrafish. Additionally, Sco-induced brain oxidative stress and increasing of acetylcholinesterase (AChE) activity were attenuated by the administration of OEO. The gas chromatography–mass spectrometry (GC-MS) analyses were used to elucidate the OEO composition, comprising thymol (38.82%), p-cymene (20.28%), and γ-terpinene (19.58%) as the main identified components. These findings suggest the ability of OEO to revert the Sco-induced cognitive deficits by restoring the cholinergic system activity and brain antioxidant status. Thus, OEO could be used as perspective sources of bioactive compounds, displaying valuable biological activities, with potential pharmaceutical applications.     

Synthesis,Characterization, and Reactivity of Cationic Palladium(II) and Platinum(II) Iodo Complexes Containing a Linear or a Tripodal Aminophosphine. The X‐Ray Crystal Structures of [Pd{HN(CH2CH2PPh2)2}I]I and [Pd3{N(CH2CH2PPh2}3)2I4]I2

The complexes [M(PNHP)I]I (PNHP = bis[2‐(diphenylphosphino)ethyl]amine; M = Pd ( 1 ), Pt ( 2 )) and [M(NP₃)I]I (NP₃ = tris[2‐(diphenylphosphino)ethyl]amine; M = Pd ( 3 ), Pt ( 4 )) were prepared by interaction of the appropriate aminophosphine in CH₂Cl₂ with aqueous solutions containing [MCl₄]^2— salts and NaI in a ratio 1:4. Complexes 2 and 3 form the polynuclear compounds [Pt₂(PNHP)₃]I₄ ( 2a ) and [Pd₃(NP₃)₂I₄]I₂ ( 3a ) in the presence of coordinating solvents such as the mixture CD₃OD/D₂O/DMSO‐d₆ and CH₂Cl₂/CH₃OH, respectively. Complex 1 consists of distorted square‐planar cations [Pd(PNHP)I]⁺ and iodide anions able to establish short N‐H···I interactions of 2.850Å. The aminophosphine adopts a boat conformation and is coordinated to palladium in a tridentate chelating fashion. The crystal structure for cations of 3a reveals the presence of two types of distorted square‐planar Pd^II atoms, PdNP₂I and trans‐PdP₂I₂, NP₃ acting as tridentate chelating and bridging ligand, respectively. On the basis of ³¹P {¹H} NMR data it has been shown that each distorted square‐planar Pt(II) centre of 2a contains one PNHP acting as tridentate chelating ligand with the other aminophosphine bridging the two metals via the P atoms. Complexes 3 and 4 were shown by ³¹P {¹H} NMR to have the metal atom bound to the three P atoms of NP₃ and one iodo ligand. Additions of AcCysSH and GSH to 4 result, by a ring‐opening process, in the formation of [Pt(NP₂PO)(SR)] (RS = Acys ( 4a ), GS ( 4b )) in which the ligand contains a dangling arm phosphine oxide group and the platinum atom achieves the four‐coordination involving the N atom of the aminophosphine. Compounds [Pt₂(PNHP)₃]Cl₄ ( 2a′ , 2a″ ), [PtAu(PNHP)₂I]I₂ ( 2b ), and [Pt(PNHP)(ONO₂)](NO₃) ( 2c ) were detected in some extent in solution by reaction of complex 2 with Au(tdg)Cl (tdg = thiodiglycol), AuI and excess AgNO₃, respectively. While 1 does not react with AuI, complex 3 affords the heterobimetallic complexes PdCu(NP₃)I₃ ( 5 ), PdAg₂(NP₃)I₄ ( 6 ) and PdAu(NP₃)I₃ ( 7 ) by interaction with the appropriate iodide M′I (M′ = Cu, Ag, Au) via a chelate ring‐opening.     

Chemical Composition,Antioxidant and Antimicrobial Activity of Some Types of Honey from Banat Region,Romania

Honey is a natural product with multiple health benefits. The paper presents the chemical characterization and the antioxidant and antimicrobial potential of ten types of honey (knotweed, linden, wild cherry, acacia, honeydew, oilseed rape, sunflower, phacelia, plain polyflora and hill polyflora) from the Banat region, Romania. We studied the water content, dry matter, impurities, acidity and pH of honey. We also determined the content of reducing sugar, minerals and flavonoids and the total phenolic content. All honey samples analysed showed good nutritional characteristics according to the standard codex for honey. From the analysis of the mineral content of the honey samples, we observed a variability in the macro and microminerals, influenced by the botanical origin, ranging between 0.25% (wild cherry honey) and 0.54% (honeydew). The toxic metals’ (Cd and Pb) levels met the standard for almost all samples analysed except for knotweed. The flavonoid content of the samples ranged from 9.29 mg QE/100 g for wild cherry honey to 263.86 mg QE/100 g for linden honey, and for polyphenols between 177.6 mgGAE/100 g for acacia honey and 1159.3 mgGAE/100 g for honeydew. The best antioxidant capacity was registered in the case of linden honey (79.89%) and honeydew (79.20%) and the weakest in acacia (41.88%) and wild cherries (50.4%). All studied honey samples showed antimicrobial activity, depending on the type of honey, concentration and strain analysed. The novelty of this study is given by the complex approach of the study of honey quality, both from the perspective of chemical attributes and the evaluation of the antimicrobial potential on specific strains in correlation with the botanical and geographical origin of the analyzed area.     

Effects of the Calix[4]arene Derivative Compound OTX008 on High Glucose-Stimulated ARPE-19 Cells: Focus on Galectin-1/TGF-β/EMT Pathway

Diabetic retinopathy (DR) is a neurovascular disease characterized by the reduction of retina integrity and functionality, as a consequence of retinal pigment epithelial cell fibrosis. Although galectin-1 (a glycan-binding protein) has been associated with dysregulated retinal angiogenesis, no evidence has been reported about galectin-1 roles in DR-induced fibrosis. ARPE-19 cells were cultured in normal (5 mM) or high glucose (35 mM) for 3 days, then exposed to the selective galectin-1 inhibitor OTX008 (2.5–5–10 μM) for 6 days. The determination of cell viability and ROS content along with the analysis of specific proteins (by immunocytochemistry, Western blotting, and ELISA) or mRNAs (by real time-PCR) were performed. OTX008 5 μM and 10 μM improved cell viability and markedly reduced galectin-1 protein expression in cells exposed to high glucose. This was paralleled by a down-regulation of the TGF-β/, NF-kB p65 levels, and ROS content. Moreover, epithelial–mesenchymal transition markers were reduced by OTX008 5 μM and 10 μM. The inhibition of galectin-1 by OTX008 in DR may preserve retinal pigment epithelial cell integrity and functionality by reducing their pro-fibrotic phenotype and epithelial–mesenchymal transition phenomenon induced by diabetes.     

Sterilization validation for medical devices at IRASM microbiological laboratory—Practical approaches

EN ISO 11137 established regulations for setting or substantiating the dose for achieving the desired sterility assurance level.The validation studies can be designed in particular for different types of products. Each product needs distinct protocols for bioburden determination and sterility testing.The Microbiological Laboratory from Irradiation Processing Center (IRASM) deals with different types of products, mainly for the VD_max²⁵ method. When it comes to microbiological evaluation the most challenging was cotton gauze. A special situation for establishing the sterilization validation method appears in cases of cotton packed in large quantities. The VD_max²⁵ method cannot be applied for items with average bioburden more than 1000 CFU/pack, irrespective of the weight of the package. This is a method limitation and implies increased costs for the manufacturer when choosing other methods.For microbiological tests, culture condition should be selected in both cases of the bioburden and sterility testing. Details about choosing criteria are given.     

Electromagnetic interaction in theory with Lorentz invariant CPT violation

An attempt is made to incorporate the electromagnetic interaction in a Lorentz invariant but CPT violating non-local model with particle–antiparticle mass splitting, which is regarded as a modified QED. The gauge invariance is maintained by the Schwinger non-integrable phase factor but the electromagnetic interaction breaks C, CP and CPT symmetries. Implications of the present CPT breaking scheme on the electromagnetic transitions and particle–antiparticle pair creation are discussed. The CPT violation such as the one suggested in this Letter may open a new path to the analysis of baryon asymmetry since some of the Sakharov constraints are expected to be modified.     

Influence of Mixed Solvents and Temperature on the Solution Properties of Quaternized Polysulfones

Modification of intrinsic viscosity and the preferential adsorption coefficients of quaternized polysulfones with various contents of ionic chlorine in N,N‐dimethylformamide/water and methanol/water mixed solvents was investigated at different compositions and temperatures. The polyelectrolyte effect induced by an enhanced dissociation of the ionizable groups determines both the modification of the swelling degree of the polymer coil and the difference in composition of the mixed solvent inside and outside the coil. The results obtained were correlated with the interaction parameters of the above‐mentioned polymer/solvent/solvent systems.     

Synthesis and Reactions of 2‐[1‐Methyl‐1‐(pyrrolidin‐2‐yl)ethyl]‐1H‐pyrrole and Some Derivatives with Aldehydes: Chiral Structures Combining a Secondary‐Amine Group with an 1H‐Pyrrole Moiety as Excellent H‐Bond Donor

The synthesis of compound 2 and its derivatives 6 and 8 combining a pyrrolidine ring with an 1H‐pyrrole unit is described (Scheme 2). Their attempted usability as organocatalysts was not successful. Reacting these simple pyrrolidine derivatives with cinnamaldehyde led to the tricyclic products 3b, 9b , and 10b first (Scheme 1, Fig. 2). The final, major products were the pyrrolo‐indolizidine tricycles 3a, 9a , and 10a obtained via the iminium ion reacting intramolecularly with the nucleophilic β‐position of the 1H‐pyrrole moiety (cf. Scheme 1).