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An efficient procedure for the synthesis of new enantiopure pyrrolidine-based sulfides bearing additional nitrogen donors and secondary amines based on a bicyclic 2-azanorbornane skeleton was developed. Their application as ligands in palladium-catalyzed Tsuji-Trost reactions led to high yields and up to 82% ee. [ABSTRACT FROM AUTHOR]

Chiral scaffolds of 2-azabicyclo[2.2.1]heptane and 2-azabicyclo[3.2.1]octane were used for the construction of new modular catalysts containing complexing moieties pyridine, 2,2′-bipyridine and 1,10-phenanthroline appended by an imine linkage. The coordination abilities of the new ligands towards Zn(ii) were investigated using NMR and UV spectroscopy. The plausible structures of the [ZnL2]2+ and [ZnLXn](2−n)+ complexes formed were established by comparison of the experimental and DFT-calculated NMR spectra. The catalytic application of the [ZnLXn](2−n)+-type complexes in the asymmetric aldol reaction of ketones with aromatic aldehydes produced an excess of the respective syn-aldols in up to ＞98% ee. [ABSTRACT FROM AUTHOR]

Enantiomerically pure bicyclic derivatives of 2-azanorbornane containing sulfonamide, amide, and thiourea functionalities were synthesized using aza-Diels-Alder reaction. [ABSTRACT FROM PUBLISHER]

Abstract: Chiral C 2-symmetric S,S- and Se,Se-donating ligands as well as the C 1 mixed S,Se-donating ligands were prepared from optically active 1,2-cyclohexanediol and 1,2-cyclopentanediol via the respective SN2 reactions. The bis(chalcogen) ligands obtained effectively catalyze the asymmetric allylic alkylation with enantioselectivities of up to 50% ee. [Copyright &y& Elsevier]

Two approaches to terminal alkynes based on the enantiomerically pure epimers (1S,3R,4R)- and (1S,3S,4R)- 2-azabicyclo[2.2.1]heptane aldehydes were established: i) a non-Wittig route through a dichloroalkene intermediate; and, ii) a Corey-Fuchs approach via dibromoalkene. Among various organometallic reagents tested, the use of n-butyllithium was efficient. The resulting alkynes were fully characterized, and one epimer was used in a click chemistry triazole synthesis. For one of the products containing a bulky N-Boc-proline substituent, the existence of atropisomers was observed. The absolute stereochemistry was determined by electronic circular dichroism spectroscopy (ECD) and optical rotation supported by quantum chemical simulations. [ABSTRACT FROM AUTHOR]

In the search for new antitumor agents, aminophosphonic acids and their derivatives based on octahydroquinoxalin-2(1 H )-one scaffold were obtained and their cytotoxic properties and a mechanism of action were evaluated. Phosphonic acid and phosphonate moieties increased the antiproliferative activity in comparison to phenolic Mannich bases previously reported. Most of the obtained compounds revealed a strong antiproliferative effect against leukemia cell line (MV-4-11) with simultaneous low cytotoxicity against normal cell line (mouse fibroblasts-BALB/3T3). The most active compound was diphenyl-[(1 R ,6 R )-3-oxo-2,5-diazabicyclo[4.4.0]dec-4-yl]phosphonate. Preliminary evaluation of the mechanism of action showed the proapoptotic effect associated with caspase 3/7 induction.