Abstract:
:A calix[4]arene was designed to reversibly dimerize and form an egg-shaped enclosure. Adhesive interactions in the assembly were provided by four self-associating ureas, which form a cyclic array containing 16 hydrogen bonds. The synthesis was completed in four steps from the previously described O,O',O",O"'-tetrabenzylcalix[4]arene. Evidence for dimerization of the calixarene tetraurea was provided by H NMR, mass spectrometry, and the observation of encapsulated molecules. The resulting cavity was of sufficient size to capture guests such as ethyl benzene and p-xylene.
journal_name
Proc Natl Acad Sci U S Aauthors
Shimizu KD,Rebek J Jrdoi
10.1073/pnas.92.26.12403subject
Has Abstractpub_date
1995-12-19 00:00:00pages
12403-7issue
26eissn
0027-8424issn
1091-6490journal_volume
92pub_type
杂志文章abstract::Compensatory ventilatory responses to increased inspiratory loading are essential for adequate breathing regulation in a number of pulmonary diseases; however, the human brain sites mediating such responses are unknown. Midsagittal and axial images were acquired in 11 healthy volunteers during unloaded and loaded (30 ...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.92.14.6607
更新日期:1995-07-03 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1525093113
更新日期:2016-02-23 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1521160113
更新日期:2016-04-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0705522104
更新日期:2007-10-09 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.1912571116
更新日期:2019-12-10 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.16.8787
更新日期:1996-08-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.73.9.3258
更新日期:1976-09-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2003-09-02 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2008-03-25 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.9.4025
更新日期:1996-04-30 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.84.10.3132
更新日期:1987-05-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.86.24.9692
更新日期:1989-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1984-11-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.0509033102
更新日期:2005-12-06 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.71.12.4965
更新日期:1974-12-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1999-09-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2020-07-21 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2017-10-24 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2002-02-05 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.79.21.6722
更新日期:1982-11-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2008-08-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.93.24.13659
更新日期:1996-11-26 00:00:00