Bromoalkoxylation of dihydropyran with bromine and 1-borneol, followed by dehydrobromination and epoxidation, afforded trans-2-1- bornyloxy-3,4-epoxytetrahydropyran as a major product. This was treated with sodium phenylselenide to give a 1:1 mixture of (2R,3R,4R)- 2-1-bornyloxy-3-hydroxy-4-phenylselenotetrahydropyran and its (2S,3S, 4S) diastereomer. Elimination of the selenoxide, derived from oxidation of the former with hydrogen...
Amphidinolide B₁ is one of the most potent cytotoxic compounds in the
amphidinolide family. Its bioactivity and intriguing structure has drawn
attention from synthetic chemists. Although numerous synthetic efforts toward
the total synthesis of amphidinolide B₁ have been published, it still remains an
unconquered synthetic target.
One of the unique...
A spectral investigation of the molecular vibration region of
the potassium sulfate crystal system was undertaken. This study was
initiated to establish the feasibility of using this crystal as a
host matrix for ammonium sulfate. Since these two systems are isomorphic
and have unit cells of nearly equal volume the...
The structural architecture present in marine toxin azaspiracid - 20 stereocenters, 9 rings, 3 separated spirocenters - has attracted considerable synthetic attention. Our efforts toward the synthesis of azaspiracid have led to the completion of both C₁-C₂₆ northern and C₂₇-C₄₀ southern halves. Herein, the
synthesis of southern FGHI ring system...
Perdeutero-spiropentane (C₅D₈) has been synthesized and infrared and Raman spectra are reported for the first time. Wavenumber assignments are made for most of the fundamental vibrational modes. Gas phase infrared spectra were recorded at a resolution (0.002 cm⁻¹) sufficient to resolve individual rovibrational lines and show evidence of strong Coriolis...
