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An in situ generated catalyst were developed from readily available Ru[H.sub.2][(P[Ph.sub.3]).sub.4], an N-heterocyclic carbene (NHC) precursor, NaH, and acetonitrile. The prepared catalyst exhibited high activity for the amide synthesis directly from either alcohols or aldehydes with amines.

Stereoselective total syntheses of natural (+)-varitriol, (-)-varitriol, 5'-epi-(+)-varitriol and 4'-epi-(-)-varitriol are achieved with use of D-mannitol as a chiral pool material. The Heck reaction is used for assembling the olefinic sugar moiety and the aromatic triflate moiety.

A highly convergent total synthesis of bitungolide F is described that has lead to the assignment of its absolute stereochemistry. Modified Evan's syn-aldol reaction is used for installing the stereochemistries at the C4 and C5 centers and the stereochemistry at C9 is introduced by using hydroxyl-directed reduction of the C9 keto.

The enzyme isopentenylpyrophosphate-dimethylallylpyrophosphate isomerase catalyzes the of isopentenyl pyrophospate to form dimethylallyl pyrophosphate, which is used in protein prenylation and in cholesterol and ergosterol biosynthesis. The structure of the enzyme is determined because the enzyme is a potential drug target.