A synthetic pathway leading to (+)-fusicoauritone (1) is highlighted by the use of a Julia condensation for preparation of an eleven-membered dolabelladienone precursor for subsequent Nazarov cyclization to yield the 5-8-5 tricyclic diterpene skeleton.

No abstract

MDL 103371 is a N-methyl-D-aspartate (NMDA)-type glycine receptor antagonist for the potential treatment of stroke. Evaluation of five different synthetic routes, which included Stille, Suzuki, enol ether, Knoevenagel, and the Mukaiyama coupling reactions, revealed the Knoevenagel approach superior for preparing large quantities of drug substance for evaluation. The overall process utilized some classical chemistry. Fischer indole cyclization, followed by a Vilsmeier-Haack formylation and a Knoevenagel condensation gave immediate access into the proper carbon framework of the target molecule. A unique hydrogenation cataylst and solvent system for a nitro reduction, followed by a two step acid-base hydrolysis of a nitrile gave the crude product. Purification was accomplished by a potassium salt crystallization followed by a Schiff base formation to give MDL 103371 in nine steps in an overall yield of 38%.

No abstract

Direct asymmetric reductive amination represents an efficient means of converting ketones to α-chiral primary amines, but reported examples are very limited. We describe the development of two sets of Ru-catalyzed conditions for the direct conversion of an aryl methyl ketone to a pharmaceutically relevant chiral primary amine. In the presence of NH3, NH4Cl, and H2, a readily available dtbm-Segphos ruthenium catalyst can be used to prepare the desired chiral primary amine with >93% ee on multikilogram scale.