C O M M U N I C A T I O N S
Scheme 3
in the starting materials. Bridged pentacycle 22 was the only product
isolated from the cycloaddition of diene 15.
This initial report details the straightforward assembly of three
monomers into diverse oligomers and the rigidification of these
compounds into different molecular architectures. Future research
will attempt to define additional chemical transformations capable
of altering product structures and to annotate the resulting products
using small-molecule screens. The discovery of a cascade annulation
reaction of a linear ene-diyne illustrates the ability of the oligo-
merization/folding process to enable chemical discovery in addition
to generating skeletally diverse small molecules.
Acknowledgment. We thank the National Cancer Institute
(2PO1 CA-78048) for support of this research, along with Bang
Wong, Chris Johnson, and Drs. Ethan Perlstein, Greg Copeland,
and Damian Young for their assistance. D.A.S. is grateful to the
National Institutes of Health for funding support. S.L.S. is an
Investigator at the Howard Hughes Medical Institute in the
Department of Chemistry and Chemical Biology, Harvard Univer-
sity.
Scheme 4
Supporting Information Available: Methods to perform experi-
ments and to determine the constitution and stereochemistry of all
compounds. This material is available free of charge via the Internet
References
Scheme 5
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