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Research has been conducted on the 2-aziridinesulfinimines. The synthesis of these compounds and their diastereoselective reactions with phosphite anions carried out in producing (2-aziridinyl)-alpha-aminophosphonic acid derivatives are described.

Research has been conducted on chiral sulfinimines. The authors describe the reactions of these compounds, derived from aliphatic aldehydes, with cyanotrimethylsilane carried our in the presence of CsF to produde alpha-amino nitriles.

A general and efficient Pd/phosphoramidite thioether complex-catalyzed asymmetric N-allylic alkylation of hydrazones with allylic acetates has been developed for the first time. The reaction allows for the preparation of various valuable N-substituted hydrazones with generally good yields and excellent enantioselectivities. Minor structural modification of the ligand resulted in opposite enantiomers, enabling enantiodivergent synthesis of products by the same catalytic system. [ABSTRACT FROM AUTHOR]

A Cu(OAc)2-catalyzed domino tricyclization between naphthalene-1,8-diamine and 2-(phenylethynyl)benzaldehyde is described, enabling aerobic oxidative dehydrogenation coupling to access heptacyclic quinolizino[3,4,5,6-kla]perimidines. In this reaction, the formation of three new rings and four new bonds was achieved in a functional-group-compatible fashion, allowing a facile method toward fused aza-heterocycles containing both quinolizine and perimidine moieties. [ABSTRACT FROM AUTHOR]

In vivo methylation and demethylation processes were simultaneously investigated in freshwater tilapia after dietary exposure to mercury (198Hg(II) and methyl200Hg). During one month dietary exposure followed by two month depuration, both MeHg and THg increased continuously in muscle tissues but decreased in liver during depuration, indicating the inter-organ transportation of MeHg from liver toward muscle. Direct evidence of in vivo net methylation process in freshwater tilapia was observed. Specifically, 0.67-1.60% of the ingested Hg198(II) was converted into Me198Hg and deposited in fish muscle at the end of depuration. The methylation potential in terms of methylated fraction was elevated at higher temperature and decreased at higher dosage. However, no direct evidence of MeHg demethylation was observed. In contrast to some previous reports of dose-dependent demethylation, the percentage of MeHg in the liver decreased significantly with increasing THg concentrations, likely due to the faster inter-organ MeHg transportation from liver toward muscle. Our study demonstrates the important role of organ- and species-specific biodynamics in understanding mercury transformation and speciation in fish. The observed in vivo methylation process in tilapia was slow, suggesting that the high %MeHg in fish should be mainly derived from MeHg ingestion instead of in vivo transformation. [ABSTRACT FROM AUTHOR]

Analogues of the known H1-antihistamine R-dimethindene were profiled as potential agents for the treatment of insomnia. Several highly selective compounds were efficacious in rodent sleep models. On the basis of overall profile, indene 1dand benzothiophene 2ahad pharmacokinetic properties suitable for evaluation in night time dosing. Compound 2adid not show an in vivo cardiovascular effect from weak hERG channel inhibition. [ABSTRACT FROM AUTHOR]