Recovery of aluminum from composite propellants

Aluminum was recovered from solid rocket propellant containing a small amount of oxidizer by depolymerizing and dissolving propellant binders (containing functional or hydrolyzable groups in a solution of sodium methoxide) in an alcohol solvent optionally containing an aliphatic or aromatic hydrocarbon co-solvent. The solution was filtered to recover substantially all the aluminum in active form

ppm Pd-catalyzed, Cu-free Sonogashira couplings in water using commercially available catalyst precursors.

A new catalyst that derives from commercially available precursors for copper-free, Pd-catalyzed Sonogashira reactions at the sustainable ppm level of precious metal palladium under mild aqueous micellar conditions has been developed. Both the palladium pre-catalyst and ligand are commercially available, bench stable, and highly cost-effective. The catalyst is applicable to both aryl- and heteroaryl-bromides as educts. A wide range of functional groups are tolerated and the aqueous reaction medium can be recycled. An application to a key intermediate associated with an active pharmaceutical ingredient (ponatinib) is discussed

First principles investigation of ferroelectricity in epitaxially strained Pb2_2TiO4_4

The structure and polarization of the as-yet hypothetical Ruddlesden-Popper compound Pb$_2$TiO$_4$ are investigated within density-functional theory. Zone enter phonons of the high-symmetry K$_2$NiF$_4$-type reference structure, space group $I4/mmm$, were calculated. At the theoretical ground-state lattice constants, there is one unstable infrared-active phonon. This phonon freezes in to give the $I2mm$ ferroelectric state. As a function of epitaxial strain, two additional ferroelectric phases are found, with space groups $I4mm$ and $F2mm$ at compressive and tensile strains, respectively.Comment: 4 pages, 4 figure

Design, synthesis and biological activity of selective hCAs inhibitors based on 2-(benzylsulfinyl)benzoic acid scaffold

A large library of derivatives based on the scaffold of 2-(benzylsulfinyl)benzoic acid were synthesised and tested as atypical inhibitors against four different isoforms of human carbonic anhydrase (hCA I, II, IX and XII, EC 4.2.1.1). The exploration of the chemical space around the main functional groups led to the discovery of selective hCA IX inhibitors in the micromolar/nanomolar range, thus establishing robust structure-activity relationships within this versatile scaffold. HPLC separation of some selected chiral compounds and biological evaluation of the corresponding enantiomers was performed along with molecular modelling studies on the most active derivatives

Sulfonium Salts as Leaving Groups for Aromatic Labelling of Drug-like Small Molecules with Fluorine-18.

Positron emission tomography (PET) is unique in that it allows quantification of biochemical processes in vivo, but difficulties with preparing suitably labelled radiotracers limit its scientific and diagnostic applications. Aromatic [(18)F]fluorination of drug-like small molecules is particularly challenging as their functional group compositions often impair the labelling efficiency. Herein, we report a new strategy for incorporation of (18)F into highly functionalized aromatic compounds using sulfonium salts as leaving groups. The method is compatible with pharmacologically relevant functional groups, including aliphatic amines and basic heterocycles. Activated substrates react with [(18)F]fluoride at room temperature, and with heating the reaction proceeds in the presence of hydrogen bond donors. Furthermore, the use of electron rich spectator ligands allows efficient and regioselective [(18)F]fluorination of non-activated aromatic moieties. The method provides a broadly applicable route for (18)F labelling of biologically active small molecules, and offers immediate practical benefits for drug discovery and imaging with PET

Ruthenium Carbene Mediated Metathesis of Oleate-Type Fatty Compounds

The complexes RuCl2(PCy3)2(=CHPh), 1, and RuCl2(PCy3)(H2IMes)(=CHPh), 2, proved to be active catalysts for the self-metathesis of oleate-type fatty compounds containing the ester, hydroxyl, epoxy and carboxylic acid functional groups. At elevated reaction temperatures 2 showed a higher activity, stability and lower selectivity for primary metathesis products compared to 1. A profound influence of organic functional groups on catalyst activity and selectivity was found and from relative activities and selectivities 2 has proved to be more resistant to deactivation by polar functional groups and more inclined to promote double bond isomerisation than 1. The observed catalyst deactivation by oxygen-containing functional groups could be attributed to a phosphine displacement side reaction

A STUDY ON CHRONIC OTITIS MEDIA ACTIVE MUCOSAL TYPE WITH SINUSITIS AS FOCAL SEPSIS

AIM : To establish the role of Sinusitis as Focal sepsis in Chronic Otitis media active mucosal disease, to emphasizethe need of proper diagnostic endoscopic evaluation and improvement in middle ear mucosal disease status afterfunctional endoscopic sinus surgery.METHODS : 60 Patients in the age groups of 18-49 years Chronic otitis media active mucosal disease wereidentified and screened for evidence of Focal Sepsis in Pasanasal sinus by Diagnostic Nasal endoscopy andcomputed tomography of paranasal diseases. Then Functional endoscopic sinus surgery was done to clear sinusitisand middle ear mucosal disease status assessed.RESULTS :Evaluation revealed that sinusitis in these patients was the cause for persistent discharge. All patients hadone or more evidence of sinusitis like pus in middle meatus, deviated nasal septum and turbinoseptal deformities,prominent enlarged bullae, enlarged middle turbinate on DNE and CT. The otoendoscopy showed inflamed andboggy middle ear mucosal status. All patients underwent septoplasty/FESS depending on findings. Out of 60patients 52 patient had improvement in middle ear mucosal status with surgery.In the adult population sinusitis is the most important focal sepsis in case of persistent ear discharge in ChronicOtitis Media active mucosal type of disease.A proper diagnostic nasal evaluation of all Chronic Otitis Media activemucosal type of patients is necessary in comprehensive management of the disease. The clearance of sinusitis hasimproved the middle ear mucosal status. Unilateral ear discharge is associated with sinusitis only on thecorresponding side, which is in concurrence with our study. Functional endoscopic sinus surgery has emerged as thebest procedure for clearance of sinusitis.

Sporopollenin, the least known yet toughest natural biopolymer

© 2015 Mackenzie, Boa, Diego-Taboada, Atkin and Sathyapalan. Sporopollenin is highly cross-linked polymer composed of carbon, hydrogen, and oxygen that is extraordinarily stable and has been found chemically intact in sedimentary rocks some 500 million years old. It makes up the outer shell (exine) of plant spores and pollen and when extracted it is in the form of an empty exine or microcapsule. The exines resemble the spores and pollen from which they are extracted, in size and morphology. Also, from any one plant such characteristics are incredible uniform. The exines can be used as microcapsules or simply as micron-sized particles due to the variety of functional groups on their surfaces. The loading of a material into the chamber of the exine microcapsule is via multi-directional nano-diameter sized channels. The exines can be filled with a variety of polar and non-polar materials. Enzymes can be encapsulated within the shells and still remain active. In vivo studies in humans have shown that an encapsulated active substance can have a substantially increased bioavailability than if it is taken alone. The sporopollenin exine surface possesses phenolic, alkane, alkene, ketone, lactone, and carboxylic acid groups. Therefore, it can be derivatized in a number of ways, which has given rise to applications in areas, such as solid supported for peptide synthesis, catalysis, and ion-exchange chromatography. Also, the presence of the phenolic groups on sporopollenin endows it with antioxidant activity

Direct 3D Printing of Catalytically Active Structures

3D printing of materials with active functional groups can provide customdesigned structures that promote chemical conversions. Herein, catalytically active architectures were produced by photopolymerizing bifunctional molecules using a commercial stereolithographic 3D printer. Functionalities in the monomers included a polymerizable vinyl group to assemble the 3D structures and a secondary group to provide them with active sites. The 3D-printed architectures containing accessible carboxylic acid, amine, and copper carboxylate functionalities were catalytically active for the Mannich, aldol, and Huisgen cycloaddition reactions, respectively. The functional groups in the 3D-printed structures were also amenable to post-printing chemical modification. As proof of principle, chemically active cuvette adaptors were 3D printed and used to measure in situ the kinetics of a heterogeneously catalyzed Mannich reaction in a conventional solution spectrophotometer. In addition, 3D-printed millifluidic devices with catalytically active copper carboxylate complexes were used to promote azidealkyne cycloaddition under flow conditions. The importance of controlling the 3D architecture of the millifluidic devices was evidenced by enhancing reaction conversion upon increasing the complexity of the 3D prints