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3-cyano-1,11-dihydro-4,5-diphenyl-2-thioxopyrido[2,3-b](1,5)benzodiazepine 2 and 3-(2′-cyano-1′-phenyl-2′-ethanethiocarboxamide)-4-phenyl-1(H)(1,5)benzodiazepin2-one 3 were prepared via the reaction of 1,3-dihydro-4-phenyl-(1,5)benzodiazepin-2-one 1 with benzylidenecyanothioacetamide. Compound 2 was treated with halo compounds to give the corresponding S-alkylated compounds 4 a−c, which underwent as intramolecular ring closure to thieno[3,2.5,6]pyrido[2,3-b](1,5)benzodiazepines 5 a−c under PTC conditions. One-pot syntheis of compounds 5 a−c was achieved via the reaction of compound 2 with the appropriate halo compound under PTC conditions. Compound 1 and 1-ethyl-4-phenyl-(1,5)benzodiazepin-2-one 9 were treated with carbon disulfide or phenylisothiocyanate and active nitriles to afford 4-thioxothiopyrano[4,3-b](1,5)benzodiazepines 8 and 10–14. Treatment of compound 10 with phenylisothiocyanate or acetic anhydride yielded oxazino-and pyrimido[4,5-b]thiopyrano-[4′,3′-b′](1,5)benzodiazepine 15 and 17. The rea...

Phase transfer catalysts (PTCs) have been widely used for the synthesis of organic compounds particularly in both liquid-liquid and solid-liquid heterogeneous reaction mixtures. They are known to accelerate reaction rates by facilitating formation of interphase transfer of species and making reactions between reagents in two immiscible phases possible. Application of PTC instead of traditional technologies for industrial processes of organic synthesis provides substantial benefits for the environment. On the basis of numerous reports it is evident that phase-transfer catalysis is the most efficient way for generation and reactions of many active intermediates. In this review we report various uses of PTC in syntheses and reactions of five-membered heterocycles compounds and their multifused rings.

Some new chromeno[2,3-b]pyrimidines, chromeno[3,2-c]pyridines, chromeno[2,3-b]pyridines and 3-chromenyl-1,3-thiazines were synthesized via the synthetic studies of the reaction of 2-imino-2H-chromen-3-thiocarboxamide with some aromatic aldehydes, active nitriles, and their ylidene derivatives.

The velocities of propagation of longitudinal and transverse ultrasonic waves in epoxidized natural rubber-ethylene propylene diene monomer (ENR-EPDM) blends with EPDM content of 0,25,50,75 and 100 weight percent were measured at a frequency of 2 MHz using pulse echo method. Density of the rubber blend was also measured. Longitudinal modulus, shear modulus, Young's modulus, bulk modulus, Poisson's ratio, crosslink density, and microhardness, of the rubber blends were then calculated. The variations of these parameters with the content of EPDM have been discussed, based on the structural changes of the network.

Thienopyrazole 2, 3, 5, or 6 and thienopyrazolothiazepine 7, 9, and 11 derivatives were prepared via the reaction of the 3-aminopyrazoline-5-one 1 with CS2 and different molar ratio of a variety of halo compounds having an active methylene under PTC conditions. Also, treatment of 1 with CS2 and alcoholic KOH in 2:1:1 molar ratio afforded dipyrazolopyridine derivatives 12 and 14. On other hand, the pyrazolothiadiazineone derivative 13 was obtained by treating compound 1 with CS2 and alcoholic KOH in 1:2:2 molar ratio. Under PTC conditions, compound 1, CS2, and ethyl cyanoacetate or malononitrile to gave the pyrazolopyridine derivatives 16 and 17. Coupling of compound 1 with diazonium acetates afforded the hydrazone derivatives 18a,b, which were oxidized with bromine to give pyrazolotriazoles 19a,b or cyclized with aldehydes to give pyrazolotriazine derivatives 20a–e. Bromination of compound 1 afforded monobromopyrazole derivative 21, which could be condensed to a dipyrazolopyrazindione 23. Finally, the dibromopyrazole derivative 22 was cyclized with 2-mercaptoethanol or o-phenylenediamine to give the spiropyrazoles 24a,b. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:211–217, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10129

The reaction of compound 1 with CS 2 and different active halo compounds gave the corresponding thiophene derivatives 2a,b-4a,b , whereas treatment of compound 1 with CS 2 and active methylene compounds afforded the corresponding thiopyran derivatives 5a,b , 6a,b , 7 , and 8 . Also, 1,3-thioxane derivatives 9 and 10 were obtained by reacting compound 1 with CS 2 and different cycloalkanones. Thiophene and pyrrolidene derivatives 11 , 12a,b , and 13a,b were obtained by reacting compound 1 with phenyl isothiocyanate and different halo compounds. The active methylene compounds and/or cycloalkanones were treated with compound 1 in the presence of phenyl isothiocyanate to give pyridines, thiopyran and oxazine derivatives 14a,b-16a,b , 17a-19a , and 19b , respectively.

Heterocyclization reaction of 1-phenylpyrazolidine-3,5-dione with some active nitriles and acrylonitriles is described. These cyclization reactions afforded novel heterocyclic derivatives such as pyrano[2,3-c]pyrazoles, pyrazolyl-thiazole, pyrazolyl-1,3-thiazines, and pyrazolyl-1,3-oxathiino[6,5-c]pyrazoles. Heating 1-phenylpyrazolidine-3,5-dione alone under phase transfer catalysis conditions afforded the tricyclic dipyrazolofurandione. The structure of the new products has been characterized by IR, NMR, mass spectra, and their elemental analyses.

Cloud services based on data center networks are becoming very important. Data centers host computing and storage resources, and these resources are served to customers through a network of data centers. Protecting such a network from disasters like earthquakes, hurricanes and terrorist attacks is crucial. In this paper, we propose the use of multiple routing configurations (MRC) IP fast reroute recovery process for data center disaster recovery. A demonstration of how this recovery scheme can be applied is shown. Also, we discuss the impact of the MRC recovery process on the post failure load distribution over network links and how this impact can be minimized. We propose a manual technique to minimize the impact of MRC and compare it to an automatic technique called modified MRC. Both the advantages and disadvantages of the two techniques are outlined. We conclude that a newer technique is needed that overcome the above mentioned disadvantages. The new technique should not manipulate link weights to achieve good load distribution. Our proposed new technique will implement unequal weight load balance inside open shortest path first (OSPF) and it is used with MRC. The new technique achieves good load distribution while overcoming all disadvantages.

The reaction of both of coumarin and 6-nitrocoumarin hydrazones (1,4) with alkyl(aryl)isothiocyanate afforded the corresponding 3-N[alkyl(aryl)thioamido] coumarins 3a-d or benzopyrano[2,3-c]pyrazole-3-thione derivatives 6a-d , respectively. Compounds (3a-d) were used as key intermediates for the preparation of benzopyrano-pyridine derivatives (7a-d & 10a) or benzopyranoazepine derivatives 8a,c & 12a-d through the reaction with different acyl halides or ethoxymethylenemalononitriles and subsequent cyclization. Biological activity of some new compounds against Gram +ve and Gram -ve were given.

A new series of pyridines 2a,b , (1,8) naphthyridines 3a,b and diazepines 4a,b were synthesized in one-pot reaction under phase-transfer catalysis conditions (PTC) starting with cyanoketene S,S-acetals 1 and cyanothioacetamide, cyanoacetamide or cyanoacetohydrazide in different molar ratios. The reaction of 2a with halo compounds in equimolar ratio gave thienopyridines 5a-d , while on using 1:2 molar ratio afforded pyrrolothienopyridines 6a-d. Also, bis thieno (1,8) naphthyridines 7a-d , bis-pyrrolo (1,8) naphthyridine 9 and bis (1,6) naphthyridines 10a-c were obtained by treating (1,8) naphthyridine 3a with the suitable reagents.

Coumarin and 6-nitrocoumarin hydrazones (2a,b), respectively, were prepared via the reaction of 2-thiocoumarin (1a,b) derivatives with hydrazine hydrate. The hydrazones were used as key intermediates for the preparation of some benzopyrano[2,3-c]pyrazoles (21-24) through the reaction of different acyl halides and subsequent cyclization in N,N-dimethylaniline. Benzopyrano[2,3-c]pyrazole-3-thione (25a,b) was prepared by the reaction of 1a with CS2 on which some alkylation, acylation and Mannich reactions were studied. Alternative procedures, other reactions and biological activity of some new compounds were given.

Some new heterocyclic systems 2-9 were obtained through the reaction of 4-amino-5-mercapto-3-trifluoromethyl-1,2,4-triazole (1) with ylidenemalononitriles, 1,3-diketones, halonitriles, active nitriles, aromatic aldehydes or ketones. Also spiro systems 10-12 were achieved in one pot synthesis by addition of compound 1 to isatine, cycloalkanones or ylidenenitriles followed by cyclization. The reaction of compound 1 with 3 [di(me-thylthio)-methylene] pentan-2,4-dione afforded compound 13 treated with cycloalkanones to give compounds 14.

Monodisperse albumin microspheres were successfully prepared by both chemical or thermal hardening methods via membrane emulsification using microporous glass membranes with uniform pore sizes. The monodispersity of the microspheres was found to depend strongly on parameters such as albumin concentration, emulsifier concentration, and volume ratio of the internal aqueous phase (albumin solution) to the dispersion medium (organic solvent). The optimum conditions for obtaining monodisperse albumin microspheres are described.

Investigations were made to prepare the inclusion compounds of Benzthiazide (BTZ) with b-cyclodextrin (b-CD), g-cyclodextrin (g-CD) and dimethyl-b-cyclodextrin (DMCD) in solid powdered form by the freeze-drying and the grinding methods. The freeze drying and grinding methods were successful in obtaining the inclusion compounds of BTZ with the cyclodextrins (CDs). All the inclusion compounds obtained via freeze drying and grinding methods were in powdered form. It was shown by X-ray diffractometery that the inclusion compounds obtained by the two methods were amorphous. Clear differences in infrared (IR) absorption spectroscopy and differential scanning calorimetry were observed between the inclusion compounds and the physical mixtures of BTZ-CDs. Furthermore, inclusion complexation of BTZ with g-CD, DMCD and b-CD in aqueous solutions were confirmed by the solubility method. The solubility curves of BTZ-g-CD and BTZ-DMCD were typical AL type curves while the solubility curve with b-CD can be classified as type Ap. The apparent stability constants, Kc, were calculated from the slope and intercept of the solubility diagrams 1110 M-1, 3053 M-1 and 1268 M-1 respectively. The dissolution rate of BTZ from the inclusion complexes was much more rapid than that of the BTZ alone. The enhanced dissolution rate may be due to the decrease in crystallinity and the increase in apparent solubility of the drug of the freeze-dried and ground samples, as expected from X-ray diffractometery and solubility study.

The reacton of 5- phenyl - 1,3,4 - oxadiazol-2-thione 1 with hydrazine hydrate in refluxing n-butanol afforded benzoylcarbohydrazide 2 which was cyclized to 4-amino-3-chloro-5-phenyl-1,2,4-triazole 3. Compound 3 was used for the synthesis of some new di-or polyheterocyclic derivatives via its reaction with anilines and treating the products with bidentates.

Some new functionally substituted thiopyranes and 1,3-dithiolanes were obtained in a one-pot reaction using phase transfer catalysis conditions (PTC) starting with some active methylene compounds, carbon disulphide or phenyl isothiocyanate and α,β-unsaturated nitriles. The structure of the new compounds was assigned.

The reacton of 5- phenyl - 1,3,4 - oxadiazol-2-thione 1 with hydrazine hydrate in refluxing n-butanol afforded benzoylcarbohydrazide 2 which was cyclized to 4-amino-3-chloro-5-phenyl-1,2,4-triazole 3. Compound 3 was used for the synthesis of some new di-or polyheterocyclic derivatives via its reaction with anilines and treating the products with bidentates.

Coumarin and 6-nitrocoumarin hydrazones (2a,b), respectively, were prepared via the reaction of 2-thiocoumarin (1a,b) derivatives with hydrazine hydrate. The hydrazones were used as key intermediates for the preparation of some benzopyrano[2,3-c]pyrazoles (21-24) through the reaction of different acyl halides and subsequent cyclization in N,N-dimethylaniline. Benzopyrano[2,3-c]pyrazole-3-thione (25a,b) was prepared by the reaction of 1a with CS2 on which some alkylation, acylation and Mannich reactions were studied. Alternative procedures, other reactions and biological activity of some new compounds were given.

The molecular behavior of flufenamic acid (FFA) was investigated in the physical and ground mixtures with two types of florite, florite R (FR) and florite S (FS). FR is mainly composed of porous calcium silicate while the main component of FS is porous silicon dioxide. The interaction of FFA and nonporous calcium silicate was also studied. Analyses were performed by differential scanning calorimetry, powder X-ray diffraction, and infrared-spectroscopy. Storage and grinding of the mixtures of FFA and FR resulted in the transformation of FFA to the amorphous ionic state, predominantly to calcium salt, and the amorphous state of the drug was found to be more stable in mixtures of higher FR content. In the mixture of FFA and FS, longer storage or grinding was necessary to obtain the amorphous state of FFA, and no change in its chemical state was observed. Differences of the FFA molecular state in the mixtures with FR and FS were attributed to differences of the chemical composition of these additives. Nonporous calcium silicate was found to have limited ability to induce transformation of FFA to the amorphous state as it has small surface area and lacks a porous structure. Stored or ground mixtures of FFA and FR showed marked enhancement in the dissolution behavior of FFA due to the existence of FFA in the amorphous ionic form.