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Asymmetric syntheses of 3,4- and 3,4,5-substituted puiperidines,3,4-substituted pyrrolidens, and 2,3-subsituted pyrimidinones can be achieved by (-) sparteine mediated lithiation of N-Boc-N allylic and benzylic amines and conjugate addition to nitroalkenes. The 1,4-addition products serve as useful synthetic intermediates in the synthesis of highly enantioenriched products in high yields and diastereoselectovities.

Radical reducing agents for organic halides, thionoesters and isocyanides provide high yields of the related hydrocarbons, established reagents, consisting of a P-H bond. The bonds include dimethyl phosphite, diethyl phosphite, hypophosphorous acid and its salts. Hypophosphorous acid are very good agents of this kind, and can replace tri-n-butyltin hydride.

A catalytic enantioselective indium-mediated allylation of N-benzoylhydrazones in conjunction with a protonated chiral amine is described. The reaction produced enantioenriched homoallylic amines with an extremely high level of enantioselectivity and chemical yield.

A chiral ammonium salt mediated radical addition reaction with high enantioselectivity is developed that has offered a method of approaching enantioenriched chiral amines. The radical reactions are performed under metal-free, especially tin-free conditions and the chiral ammonium salts are recyclable after a simple aqueous workup.

A convenient solvent-free method for the synthesis of benzothiazole, benzimidazole, and benzoxazole derivatives has been developed using recyclable ZnO-NPs via a ball-milling strategy. The method affords environmentally friendly reaction conditions that score high on the ecoscale with the low E-factor. The process is also highly efficient even on a multi-gram scale and provides easy product isolation. [ABSTRACT FROM AUTHOR]

We synthesized a novel tripodal fluorescent receptor bearing benzimidazole motifs as recognition sites in the pods of the receptor. The recognition behavior of the receptor toward various anions was evaluated in CH3CN/H2O (9:1, v/v) solution. The receptor showed changes in fluorescent intensity only with I-, but it showed no significant changes on addition of other anions such as F-, Cl-, Br-, HSO4-, NO3-, CH3COO-, and H2PO4-. [ABSTRACT FROM AUTHOR]

A retraction of the article "Indium-Mediated Catalytic Enantioselective Allylation of N-Benzoylhydrazones Using a Protonated Chiral Amine" that appeared in a 2010 issue of the "Journal of the American Chemical Society" is presented.

A retraction is presented to the article "Highly Enantioselective Radical Addition to N-Benzoyl Hydrazones Using Chiral Ammonium Salts," by Doo Ok Jang and Sang Yoon Kim, which was published in a volume 130, 2008 issue.

Previously, we introduced a novel cationic lipid consisting of three biocompatible components, lysine, aspartic acid, and two C-14 hydrocarbon chains, named as O,O′-dimyristyl-N-lysyl aspartate (DMKD) as a potent gene transfection reagent. Recently, we have chemically synthesized another gene-transferring cationic lipid consisting of a core of glutamic acid and lysine with two C-14 hydrocarbon chains, assigned the acronym DMKE (O,O′-dimyristyl-N-lysyl glutamate). Biophysical characteristics of the cationic liposomes made of DMKE or DMKD were compared with those of conventional DOTAP liposomes. The DMKE- and DMKD-liposomes exhibited similarly stronger DNA-binding affinity than the DOTAP liposomes. Interestingly, vesicle size changes of DMKE- and DMKD-liposomes by lipoplex formation were far smaller than that of the DOTAP liposomes. Their gene-transferring capabilities were also tested in various cell-lines and compared with the control DOTAP liposomes. Under the same transfection conditions, the order of in vitro gene transfection efficiency was DMKE=DMKD>DOTAP. The pH changes (pH 5.0 – 7.4) in culture media little affected fusigenic activities of all the cationic liposomes. However, cell surface-binding affinities of the DMKE- and DMKE-lipoplexes were similar to each other, but higher than the DOTAP liposomes. In mouse studies, intravenously administered DMKE- and DMKD-lipoplexes did not exhibited superior gene expression in lungs to the DOTAP lipoplexes. Interestingly, they were more favorably transferred to the liver, not to the lungs. Particularly, under the same experimental conditions of intratumoral transfection, the DMKE lipoplexes showed more efficient gene expression in the tumor tissues than the DOTAP- and DMKD-lipoplexes. This study suggests that a small difference in the backbone structure of cationic lipid significantly affects their gene transfection capabilities. The DMKE- and DMKD-liposomes can be utilized as an efficient gene-transferring vector for hepatic or intratumoral transgene expression.Molecular Therapy (2006) 13, S77–S77; doi: 10.1016/j.ymthe.2006.08.222 [ABSTRACT FROM AUTHOR]