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A novel silica-supported meta-periodate reagent was utilized for the efficient and facile preparation of aldehydes from vicinal glycols. The oxidative cleavage reagent was effective in facilitating reactions involving vicinal diols that are soluble in aqueous alcohols. Furthermore, the scission products produced from glycol oxidative fission reactions with the gel-supported sodium periodate reagent exhibited high purity.

Experiment was conducted to show that the stereochemical outcome of the intramolecular nitrone-alkene cycloaddition (INAC) reactions of nitrones obtained from 3-O-allyl-D-hexoses is dependent only on the relative configuration at C-2,3. Therefore, 3-O-allyl-D-glucose and -D-altrose afford oxepanes selectively while 3-O-allyl-D-allose and -D-mannose yield tetrahydropyrans selectively.

Two scalable and efficient synthetic routes for the synthesis of a T-type calcium channel antagonist MK-8998 were developed from a simple pyridine building block. The key step to set the stereochemistry relied on either chiral rhodium catalyst-mediated asymmetric hydrogenation of an enamide or transamination of an arylketone that provided the corresponding product in high enantioselectivity and high yield.

The therapeutic application of nitric oxide, an endogenous cellular signaling molecule, has been limited due to the difficulty of developing stable pro-drugs with slow kinetics of NO release. Diazeniumdiolates are valuable NO donors; however, synthetic challenges have hampered their use. O 2 -alkylation or arylation of diazeniumdiolates form stable pro-drugs which have found application in hypertension, cancer, and as antimicrobial agents. The synthesis of sodium diazeniumdiolates has proven to be challenging due to hazardous reaction conditions (high N 2 O concentrations, and flammable solvents), which can lead to detonation and suffered from limited scope. We have previously disclosed that synthesis of calcium diazeniumdiolate salts are a safer and more scalable alternative. Herein, we report the expanded scope of calcium diazeniumdiolates from benzylic amines, amides, and sterically bulky amines hitherto inaccessible and a comparison of their reactivity in comparison to sodium diazeniumdiolate.

An efficient, new, and scalable semisynthesis of glucan synthase inhibitors 1 and 2 from the fermentation product enfumafungin 3 is described. The highlights of the synthesis include a high-yielding ether bond-forming reaction between a bulky sulfamidate 17 and alcohol 4 and a remarkably chemoselective, improved palladium(II)-mediated Corey-Yu allylic oxidation at the highly congested C-12 position of the enfumafungin core. Multi-hundred gram quantities of the target drug candidates 1 and 2 were prepared, in 12 linear steps with 25% isolated yield and 13 linear steps with 22% isolated yield, respectively.

A stereoselective synthesis of (R)-beta-amino acid 1 via a beta-lactam intermediate is discussed.