A New Ecological RP-HPLC Method for the Determination of Pitavastatin,Fenofibrate and Their Impurities in a Novel Fixed Dose Combination

Chromatographia - We developed a simple, rapid, ecological RP-HPLC method for the estimation of Pitavastatin (PIT), Fenofibrate (FEN), and their impurities in a novel fixed dose combination. We...     

A novel and simple route for the synthesis of 3,4‐disubstituted pyrroles

A new class of 3,4‐disubstituted pyrroles has been prepared by the reaction of 1‐aroyl‐2‐arylsul‐fonylethenes and 1,2‐diarylsulfonylethenes with tosyl methyl isocyanide.     

Synthesis of thiadiazoles,triazoles and oxadiazoles from sulfonyl acetic acids via a common route

A new class of five membered heterocycles, thiadiazoles, triazoles and oxadiazoles were prepared from sulfonyl acetic acids via acid hydrazides.     

Biocompatible hydrogels based on chitosan,cellulose/starch,PVA and PEDOT:PSS with high flexibility and high mechanical strength

Fabricating mechanically strong hydrogels that can withstand the conditions in internal tissues is a challenging task. We have designed hydrogels based on multicomponent systems by combining chitosan, starch/cellulose, PVA, and PEDOT:PSS via one-pot synthesis. The starch-based hydrogels were homogeneous, while the cellulose-based hydrogels showed the presence of cellulose micro- and nanofibers. The cellulose-based hydrogels demonstrated a swelling ratio between 121 and 156%, while the starch-based hydrogels showed higher values, from 234 to 280%. Tensile tests indicated that the presence of starch in the hydrogels provided high flexibility (strain at break?>?300%), while combination with cellulose led to the formation of stiffer hydrogels (elastic moduli 3.9–6.6 MPa). The ultimate tensile strength for both types of hydrogels was similar (2.8–3.9 MPa). The adhesion and growth of human osteoblast-like SAOS-2 cells was higher on hydrogels with cellulose than on hydrogels with starch, and was higher on hydrogels with PEDOT:PSS than on hydrogels without this polymer. The metabolic activity of cells cultivated for 3 days in the hydrogel infusions indicated that no acutely toxic compounds were released. This is promising for further possible applications of these hydrogels in tissue engineering or in wound dressings.

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Heteropoly acid catalyzed synthesis of 8-methyl-2-aryl/alkyl-3-oxabicyclo[3.3.1]non-7-ene derivatives through (3,5)-oxonium-ene reaction

A variety of aldehydes undergo a smooth coupling with (4-methylcyclohex-3-en-1-yl)methanol in the presence of 2 mol % of phosphomolybdic acid in dichloromethane to afford 3-oxabicyclo[3.3.1]non-7-ene in good yields through 3,5-oxonium-ene cyclization under mild conditions. The use of inexpensive, nontoxic, and readily available heteropoly acid catalyst makes this method simple, convenient, and environmental-friendly.     

Determination of 2-hydroxy-4-methoxybenzaldehyde in roots of Decalepis hamiltonii (Wight & Arn.) and Hemidesmus indicus R.Br

The roots of Decalepis hamiltonii and Hemidesmus indicus are aromatic and possess the crystalline compound 2-hydroxy-4-methoxybenzaldehyde as the major compound (> 90%) in their volatile oils. A gas chromatographic procedure was developed for the assay of 2-hydroxy-4-methoxybenzaldehyde in both fresh and dried roots of different origin. Benzyl butyrate was used as the internal standard. Among the methods tried, steam hydrodistillation was suitable for extraction of the volatile oils. The quantity of this aromatic compound varied from 0.03 to 0.54%.     

Minimal kinematic boundary conditions for simulations of disordered microstructures

In simulations of representative volume elements (RVEs) of materials with disordered microstructures, commonly used rigid and periodic boundary conditions (BCs) introduce additional constraints, causing: (i) boundary effects, (ii) unrealistic stiff response, (iii) artificial wavelengths in the solution fields, and (iv) suppression of solutions with localized deformation that otherwise may occur in the simulation. In this paper we define the minimal kinematic boundary conditions such that only the desired overall strain is imposed on the RVE, with no other undesirable constraints. We prove that such BCs result in a unique solution for the linear elastic case, and that the uniqueness for nonlinear problems is dependent on the pointwise positive definiteness of the incremental stiffness tensor. Upon incorporating the minimal BCs into the finite element framework, we consider, as an example, two-dimensional, linear elastic, disordered polycrystals and perform a systematic study of the effects of boundary conditions while varying the RVE size and controlling the sampling error. The results demonstrate that the minimal BCs, applicable to a RVE of any shape, are superior to other BCs, in that they give more realistic overall behaviour, reduce the required size of the RVE, and eliminate the superficial wavelengths in the solution field, ubiquitous in simulations with other boundary conditions.     

Octadecanuclear Gear Wheels by Self‐Assembly of Self‐Assembled “Double Saddle”‐Type Coordination Entities: Molecular “Rangoli”

A series of self‐assembled “double saddle”‐type trinuclear complexes of [Pd₃L′₃ L ₂] formulation have been synthesized by complexation of a series of cis‐protected palladium(II) components with a slightly divergent “E‐shaped” non‐chelating tridentate ligand, 1,1′‐(pyridine‐3,5‐diyl)bis(3‐(pyridin‐3‐yl)urea ( L ). The cis‐protecting agents L′ employed in the study are ethylenediamine (en), tetramethylethylenediamine (tmeda), 2,2′‐bipyridine (bpy), and 1,10‐phenanthroline (phen), for 1 , 2 , 3 , and 4 , respectively. The crystal structures of [Pd₃(tmeda)₃( L )₂](NO₃)₆ ( 2 ), [Pd₃(bpy)₃( L )₂](NO₃)₆ ( 3 ), and [Pd₃(phen)₃( L )₂](NO₃)₆ ( 4 ) unequivocally support the new architecture. Two of the “double saddle”‐type complexes ( 3 and 4 ) are suitably crafted with π surfaces at the strategically located cis‐protecting sites to facilitate intermolecular π–π interactions in the solid state. As a consequence, six units of the 3 (or 4 ) are assembled, by means of six‐pairs of π–π stacking interactions, in a circular geometry to form an octadecanuclear molecular ring of [(Pd₃L′₃ L ₂)₆] composition. The overall arrangement of the rings in the crystal packing is equated with the traditional Indian art form rangoli.     

Synthesis and In Vitro Anticancer Activity of Novel 1,3,4‐Oxadiazole‐Linked 1,2,3‐Triazole/Isoxazole Hybrids

A series of new 1,3,4‐oxadiazole‐linked 1,2,3‐triazole/isoxazole derivatives were designed and synthesized. All the synthesized compounds were screened for in vitro anticancer activity against four human cancer cells: HeLa (cervical), MDA‐MB‐231 (breast), DU‐145 (prostate), and HEPG2 (liver). Among 17 compounds tested, 7a , 7c , and 7d showed potent activity toward four cell lines.     

Interplay of Hydrogen and Halogen Bonds in Supramolecular Framework of Oxy-Acid Based 3-Chloroanilinium Hydrogen Sulfate,Bis(2,5-dichloroanilinium) Sulfate and 2,5-Dichloroanilinium Perchlorate Hydrate Salts

Crystallography Reports - In title compound bis(2,5-dichloroanilinium) sulfate, the equally disordered sulfate anion occupies 2-fold rotation axis with equivalent component generated through the...