Synthesis of a Model Tetracyclic Core Structure of Calyciphylline B-Type Alkaloids.

Herein, we report the enantioselective synthesis of a functionalized aza-octahydropentalene and its elaboration to a model tetracyclic core structure of calyciphylline B-type alkaloids.

Total Synthesis of Isodaphlongamine H: A Possible Biogenetic Conundrum.

Herein we describe the first synthetic efforts toward the total synthesis of isodaphlongamine H, a calyciphylline B-type alkaloid. The strategy employs a chemoenzymatic process for the preparation of a functionalized cyclopentanol with a quaternary center. This molecule is elaborated to form an enantiopure 1-aza-perhydrocyclopentalene core, representing rings A and E of all calyciphylline B-type alkaloids.

Dormant versus evolving aminopalladated intermediates: toward a unified mechanistic scenario in Pd(II)-catalyzed aminations.

Pd(II)-catalyzed alkene aminopalladation and allylic C-H activation are two competing reaction sequences sharing the same reaction conditions. This study aimed at understanding the factors that bias one or the other path in the intramolecular oxidative cyclization of two types of N-tosyl amidoalkenes. The results obtained are in accord with the initial generation of a high-energy cyclic (5- or 6-membered) aminopalladated intermediate.

Crystal structures of a bioactive 6'-hydroxy variant of sisomicin bound to the bacterial and protozoal ribosomal decoding sites.

Parasitic infections recognized as neglected tropical diseases are a source of concern for several regions of the world. Aminoglycosides are potent antimicrobial agents that have been extensively studied by biochemical and structural studies in prokaryotes. However, the molecular mechanism of their potential antiprotozoal activity is less well understood.