A number of 1‐substituted 4H,5H,6H‐[1,3]thiazolo[3,2‐a][1,5]benzodiazepinium‐11‐bromides and S‐(2‐oxo‐2‐phenyl‐X‐(p)‐ethyl)‐3‐(2‐methyl‐1H‐benzimidazol‐1‐yl) propane (or butane) thioate hydrobromides were obtained by direct reaction of the 5‐acetyl(or formyl, or anilinocarbonyl)‐substituted tetrahydro‐1,5‐benzodiazepine‐2‐thiones with aromatic α‐bromoketones. 2‐[(1‐Acetyl‐2(or 3)‐methyl‐2,3‐dihydro‐1H‐1,5‐benzodiazepin‐4‐yl) sulfanyl]‐1‐phenylethanones as intermediates of the formation of thiazolo [3,2‐a][1,5]benzodiazepine and N‐substituted 2‐methyl‐1H‐benzimidazole derivatives have been synthesized. Semiempirical AM1 calculations of a mechanism and energetic parameters for the heptatomic nucleus rearrangement to benzimidazole ring are presented. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:72–81, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20414

In this report we present results of linear and nonlinear optical properties of colloidal material consisting of triangle silver nanoparticles in distilled water. The nonlinear optical properties of the material were investigated by a Z-scan technique using femtosecond laser pulses with tunable wavelength. Nanoparticle suspension showed distinct spectra with absorption lines, emerging due to the plasmonic properties of the silver nanoparticles. Surface plasmon resonance peak change over a wide range of wavelengths from 400 to almost 1100 nm was observed when the size of silver nanoparticles varied from 20 to 150 nm. In the samples different nonlinear effects such as saturable absorption, two photon absorption and self-focusing were observed when the femtosecond pulse intensity was changed from 1 up to 100 GW/cm 2 .

Transparent and high-hardness materials have become the object of wide interest due to their optical and mechanical properties; most notably, concerning technical glasses and crystals. A notable example is sapphire—one of the most rigid materials having impressive mechanical stability, high melting point and a wide transparency window reaching into the UV range, together with impressive laser-induced damage thresholds. Nonetheless, using this material for 3D micro-fabrication is not straightforward due to its brittle nature. On the microscale, selective laser etching (SLE) technology is an appropriate approach for such media. Therefore, we present our research on C-cut crystalline sapphire microprocessing by using femtosecond radiation-induced SLE. Here, we demonstrate a comparison between different wavelength radiation (1030 nm, 515 nm, 343 nm) usage for material modification and various etchants (hydrofluoric acid, sodium hydroxide, potassium hydroxide and sulphuric and phosphoric acid mixture) comparison. Due to the inability to etch crystalline sapphire, regular SLE etchants, such as hydrofluoric acid or potassium hydroxide, have limited adoption in sapphire selective laser etching. Meanwhile, a 78% sulphuric and 22% phosphoric acid mixture at 270 °C temperature is a good alternative for this process. We present the changes in the material after the separate processing steps. After comparing different processing protocols, the perspective is demonstrated for sapphire structure formation.

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carboxylic acids of the new derivatives were synthesized by alkaline hydrolysis of the methyl esters. The direction of the cyclocondensation reaction was determined by both the structure of the diazepine ring of the initial amines and also by the structure of the α,β-unsaturated ketones. Quantum-chemical calculations have been carried out of the minimal values of the local energy of ionization and of the resonance stabilization energy on specific atoms of the initial amines.Keywords: 7-amino-1,5-diazepin-2-one, dimethyl 2-oxoglutaconate, methyl 4-oxopentenoate, local energy of ionization, cyclocondensation, resonance stabilization energy.Previously we investigated the interaction of 7-(or 8-, or 9-)amino-4-methyl-1-(or 5-)alkyl-substituted tetrahydro-1,5-benzodiazepin-2-ones with dimethyl 2-oxoglutaconate with the aim of obtaining condensed heterosystems containing a dicarboxy-substituted diazepinoquinoline fragment [1,2]. It was established that the direction of the cycloaddition reaction depends both on the position of the primary amino group in the benzene ring of the benzodiazepinone, and on the presence of a substituent in positions 1 and 5 of the diazepine ring. It was also shown that quantum-chemical calculations of the minimal values of the local ionization energy (I min ) on the electron density surface of the molecules and the resonance stabilization energy of the initial amines fortunately demonstrate the tendency of activation and deactivation of the benzene ring [2, 3]. The possibility of using quantumchemical calculations to determine the direction of ring formation of quinolines was followed in [4]. Continuing the investigations of the synthesis of condensed systems of 1,5-benzodiazepinone, we considered in the present work the direction of closure of the pyridine ring on interacting derivatives of 7-amino-4-phenyl(or methyl)-1,3,4,5-tetrahydro(or 1,3-dihydro)-2H-1,5-benzodiazepin-2-ones with α,β-unsaturated ketones under the conditions of the modified Debner-Müller reaction.