An efficient one-pot condensation for the synthesis of 1,8-dioxo-octahydroxanthene is  achieved through a condensation of aryl aldehydes and 5,5-dimethyl-1,3-cyclohexandione in the presence of  NBS. This method enjoys several advantages such as low cost, simple work up procedure and safe reaction condition. In addition, water was chosen as a green solvent.

Preparation of 4-benzyl-2-substituted phthalazin-1-one derivatives 2-8 is reported. Condensation of 4-benzyl-1-chlorophthalazine (9) with a series of different nucleophiles gave 4-benzylphthalazin-1-ylamino derivatives (10-13 and 16) and 4-amino-2-[N'-(4-benzylphthalazin-1-yl)-hydrazino]-6-arylpyrimidine-5-carbonitriles (14a,b). Interaction of 9 with ambident anions was also studied. 5-Benzyl-6...

Distillation columns are complex processes for modeling and controlling. These columns are significant parts of most chemical industries for separation of components. Control of this process is essential for achieving certain purity for products with a minimum cost. However, nonlinearities, multivariable interaction, non-stationary behavior and severity of disturbances inside the column made th...

The method of graphical vertex-condensation for enumerating perfect matchings of plane bipartite graph was found by Propp (Theoret. Comput. Sci. 303(2003), 267-301), and was generalized by Kuo (Theoret. Comput. Sci. 319 (2004), 29-57) and Yan and Zhang (J. Combin. Theory Ser. A, 110(2005), 113125). In this paper, by a purely combinatorial method some explicit identities on graphical vertex-cond...

A water soluble, Bronsted acid, 5-sulfosalicylic acid as an efficient organocatalyst was used for the synthesis of physiologically active 2-substituted benzimidazole derivatives from o-phenylenediamine and aromatic aldehydes in ethanol at reflux condition. Cost-effectiveness, use of non-hazardous solvents, metal free and commercially available catalyst, single-step, environmentally fri...

BACKGROUND Acid gastroesophageal reflux is a common problem in non-cystic fibrosis bronchiectasis and COPD. Invasive methods are used to diagnose gastroesophageal reflux, but the ability to detect pulmonary microaspiration of gastric contents using this method is unclear. A noninvasive option to detect pulmonary microaspiration is to measure pepsin in exhaled breath condensate (EBC), but this h...

In the present article we show that, although reflux method is not common for synthesis of multicomponent MoVTeNbO catalysts, an optimized metallic precursors leads to...

We describe a new condensation method for computing the submodule lattice of a module for a finite dimensional algebra over a finite field, which exploits the idea of condensation and extends it to the case of primitive idempotents. The method has been implemented in the new C version of the Meat-Axe developed at Aachen, and we give several examples which have been analysed with our method.

BACKGROUND An association between asthma and gastro-oesophageal reflux is well recognised but the underlying mechanism is unclear. One suggestion is that gastric juice is aspirated into the tracheal and upper airways but detection of these events is difficult and involves radioisotopic studies. A new method of making direct measurements of tracheal and oesophageal pH over a 24 hour period is de...

The endoscopic injection of vesicoureteric orifices with synthetic or natural materials is a widely recognized method of treating vesicoureteral reflux (VUR). The aim of this study is to present two cases of clinically significant complications following the use of dextranomer/hyaluronic acid copolymer, which led to the progression of the reflux degree, permanent infection of the urinary tract,...