Chemistry Reference
In-Depth Information
FIGURE 3.1
Functionalized triptycene monomers offer some interesting options for
construction.
!
numerous other potential 1
3 branched systems that should/could be introduced
into the lexicon of dendritic construction. In the world of molecular motors and
rotors [187], a family of 9-triptycylethynes suggests numerous isomeric possibilities.
Figure 3.1 provides an interesting approach to rigid dendritic structures and offers a
potential to evaluate the effect of symmetrical and unsymmetrical isomers.
Although briefly touched on above, the use of natural products, such as steroid
monomers possessing a 1
1) branching motif, has only scratched the
surface of possibilities. The natural products possessing branching motifs derived
from the forest or from the sea are endless but highly under utilized. For example, N-
b
!
(1
þ
1
þ
-ethoxycarbonylpropylglutarate, shi-
kimic and dehydroquinic acid, phloracetophenone, cephalosporin P1, as well as the
related helvoic and fusidic acids and from red algae, 4-hydroxy-3,5-dibromobenzyl
alcohol and 2,3-dibromo-3,4-dihydroxybenzyl alcohol, and 2,3,5-trihydroxybromo-
benzene are interesting possibilities. It is amazing how a stroll through the woods or a
scuba diving/snorkeling trip can introduce new avenues to synthetic chemistry.
-carboxyethyl-
L
-aspartic acid, ethyl
-cyano-
a
a
ACKNOWLEDGMENTS
We thank the National Science Foundation (DMR-0705015 and DMR-0812337) for
continued support over the years, the Air Force Research Office of Scientific
Research, and the Ohio Board of Regents.
REFERENCES
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1983
, 71(March-April), 141-149.
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arbres tropicaux, Masson, Paris,
1970
.
[3] F. Halle, R. A. A. Oldeman, P. B. Tomlinson,
Tropical Trees and Forests: An
Architectural Analysis, Springer, Berlin,
1982
.
[4] G. R. Newkome, Z. Yao, G. R. Baker, V. K. Gupta, J. Org. Chem.
1985
, 50(11),
2003-2004.
[5] C. J. Hawker, J. M. J. Frechet, J. Am. Chem. Soc.
1990
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