This review focuses on the development of dynamic ammonium salt catalysis for selective organic transformations conducted in our laboratory since 2002. Several important concepts in designing of catalysts are described with some examples. In particular, the practical synthesis of chiral 1,1'-binaphthyl-2,2'-disulfonic acid (BINSA) and its application in chiral ammonium salt catalysis for the en...

Lipid membrane fluorescent probes: 23-(dipyrrometheneboron difluoride)-24-norcholesterol (BODIPY-Chol), GM1 Ganglioside (Brain, Ovine-Ammonium Salt), and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N(lissamine rhodamine B sulfonyl) (ammonium salt) (Rh-DPPE) were purchased from Avanti Polar Lipids. Cholera Toxin Subunit B (CTXB) conjugated with Alexa488 and Alexa647 (A488CTXB, A647-CTXB) and D...

UNLABELLED Communities along Utah's Wasatch Front are currently developing strategies to reduce daily average PM2.5 levels to below National Ambient Air Quality Standards during wintertime persistent stable atmospheric conditions, or cold-air pools. Speciated PM2.5 data from the Wasatch Front airshed indicate that wintertime exceedances of the PM2.5 standard are mainly driven by high levels of ...

Reaction of primary C(55)-allylic alcohol moraprenol (WT(3)C(7-9)-OH, a polyprenol from mulberry leaves) with triethylamine in the presence of phosphorus oxychloride leads to a quaternary ammonium chloride with a good yield (72%) and high cis-stereoselectivity of the terminal isoprene unit. Cationic polyprenyl derivatives may be useful for transfection and immunological studies.

The anion of the title salt, 2C(4)H(12)N(+)·S(2)O(3) (2-)·4H(2)O, possesses approximate C(3v) symmetry. The water mol-ecules themselves engage in hydrogen bonding, forming a ribbon running along the a axis; adjacent chains are linked to the thio-sulfate anions by hydrogen bonds, forming a three-dimensional network. The cavities in the network are occupied by the tetra-methyl-ammonium counter ions.

The effect of relative humidity (RH) on aerosol formation by the semi-volatile oxidation products of the a-pinene/O3 system has been comprehensively studied. Experiments were performed in the presence of ammonium sulfate (aqueous, dry), ammonium bisulfate seed (aqueous, dry), and aqueous calcium chloride seed aerosols to ascertain their effect on the partitioning of the oxidation products. The ...