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 The
recently discovered antibiotic lactonamycin, has an hexacyclic core
structure which is unlike that of any other molecule. In addition,
lactonamycin exhibits sub-microgram/mL activity against a variety
of bacteria resistant to most current antibiotics, including methicillin
resistant (MRSA) and vancomycin resistant (VRE) strains. The remarkable
structure and biological activity of lactonamycin have generated considerable
interest, but so far no synthesis of lactonamycin has been recorded.
To date we have reported the synthesis of the CDEF ring system of
lactonamycin, in effectively 5 pots from readily available material.
Org.
Lett. 2002, 4, 1527-1529. We are
currently working on the synthesis of the ABC unit and the combination
with the DEF component to prepare lactonamycin itself. |
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 We
recently reported a prototype of the first rationally designed, chemically
powered molecular motor. With a functioning prototype in hand, the
task turned to extending the original system so a continually rotating
molecular motor would be the result. To accomplish that aim, it is
necessary to realize three subgoals: (i) must be modified so that
each blade of the triptycene is ready to be selectively armed at the
appropriate time, and there must also be included within the system
units that, with the appropriate spatial positioning and timing, (ii)
can capture and deliver Cl2C=O and (iii) can cleave the
urethane. Efforts in all three directions are underway; we recently
described (Org.
Lett. 2001, 3, 3895) a partial
solution to the third objective: cleavage of the urethane under reaction
conditions compatible with the operation and analysis of the system
as a whole. We have also carried out model studies directed toward
the solution of the second problem: selective delivery of phosgene
to only the amino group in the firing position (Org.
Lett. 2002, 4, 2653). Efforts to
assemble all the pieces are currently underway. |
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