During the positive-ion mode electrospray ionization mass spectrometry analysis of 1,4-diphenyl-3-benzoyl-1,4-dihydropyridines with methanol as the solvent, the major ion generated is one mass unit lower than the analyte, which can be rationalized as the oxidative aromatization of 1,4-dihydropyridines to pyridine cations.

mn(tpp)cl catalyzes cooxidation of olefin in the singlet oxygenation of sulfid. mn(tpp)cl is able to transfer an oxygen atom from a peroxidic intermediate generated in singlet oxygenation of sulfide to a metal ion affording metal 0x0 species which is responsible for epoxidation. this system leads to allcenes epoxidation such as styrene and cyclooctene. epoxidation of cyclohexene produces cycloh...

The Bohlmann-Rahtz pyridine synthesis and the Hantzsch dihydropyridine synthesis can be carried out in a microwave flow reactor or using a conductive heating flow platform for the continuous processing of material. In the Bohlmann-Rahtz reaction, the use of a Brønsted acid catalyst allows Michael addition and cyclodehydration to be carried out in a single step without isolation of intermediates...

Under mechanical milling conditions, direct reductive benzylizations of malononitrile and 4-methylaniline by aromatic aldehydes were achieved using a Hantzsch 1,4-dihydropyridine as the reductant.

This work deals with the development of a new family of planar chiral phosphoric acids, based on a ferrocenophane/paracyclophane scaffold. The synthetic approach has been improved by taking advantage of a chiral phosphorylating agent to access enantiomerically enriched acids via diastereomers separation. These phosphoric acids have been used as catalysts for the enantioselective H-transfer redu...

Enantioselective epoxidation reactions of some chosen reactive alkenes by a chiral Mn(III) salen catalyst were performed in H₂O employing H₂O₂ as oxidant and diethyltetradecylamine N-oxide (AOE-14) as surfactant. This procedure represents an environmentally benign protocol which leads to e.e. values ranging from good to excellent (up to 95%).

Copper-catalyzed 6-endo cyclization of N-propargylic β-enaminocarbonyls was developed for the synthesis of oxidation-labile 1,6-dihydropyridines. This synthetic method allows flexible and regio-defined assembly of various substituents at the N1, C2, C3, C4, and C6 positions of 1,6-dihydropyridines under mild conditions.

Pacemaking activity in adult substantia nigra (SN) dopamine neurons relies on L-type Ca2+ channels, but a surprising study in Nature by Chan et al. demonstrates that blockade of these channels by dihydropyridines re-establishes the pacemaking driven by sodium and HCN channels found in juvenile SN. This shift protects SN neurons in chemical models of Parkinson's disease (PD), suggesting that ele...

Incubations of the fungi Cunninghamella echinulata and Rhizopus oryzae with the sesquiterpene lactones (+)-costunolide (1), (+)-cnicin (2), (+)-salonitenolide (3), (-)-dehydrocostuslactone (4), (-)-lychnopholide (5), and (-)-eremantholide C (6) were perfomed. Incubation of 1 with C. echinulata afforded Delta11(13)-dihydrogenation and Delta1(10)-epoxidation products (7-10). C. echinulata also hy...

An efficient three component reaction with enaminones, primary amines and aldehydes resulted in easy access to 1,4-dihydropyridines with different substituents at the 1-, 3-, 4- and 5-positions. Microwaves improved the reaction yield, reducing also considerably the reaction time and the amount of solvent used. Chiral primary amines gave chiral 1-substituted-1,4-dihydropyridines. The 4-(1-naphth...