Reactivity of 1-(des-3-hydroxy-picolinoyl) pristinamycin IA

Pyridine elaboration through organometallic intermediates: regiochemical control and completeness

Pyridines carrying heterosubstituents (such as carboxy, amido, amino, alkoxy or trifluoromethyl groups or solely individual halogen atoms) can be readily and site selectively metalated. Subsequent reaction with a suitable electrophile opens rational access to a wealth of new building blocks for the synthesis of biologically active compounds. This approach relies on organometallic methods, which are both efficacious and extremely flexible as far as the substitution site and the product structure are concerned (86 references).

Approaches toward the total synthesis of the nine-membered thio-lactone core of griseoviridin

Three different approaches toward the synthesis of the macrocyclic thiolactone core of griseoviridin have been studied. Intramolecular palladium-catalyzed thiol coupling and esterification (carboxylate activation) have led to the formation of unexpected rearranged products. An intermolecular palladium-catalyzed thiol/vinyl iodide coupling followed by an esterification (alcohol activation) ultimately led to the nine-membered core of griseoviridin.