Rebek, Julius

Julius Rebek and his group were also active at about the same time with enzyme-free self-replication of chemical structures. Unhke von Kiedrowski group, he did not use nucleotides, but a rephcator consisting of an adenosine derivative and a derivative of Kemp s acid (Rotello etal., 1991 Rebek, 1994). See also Figure 7.7 for a self-replicating system not based on nucleic-acid chemistry. There are several variations of this scheme, which are not illustrated here - for reviews see Sievers etal, 1994 Orgel, 1995. 

Coordination interactions are not the only way to use self-assembly to produce closed, capsular systems capable of binding guest species in solution. Work by Julius Rebek Jr (Scripps, USA)43 has shown that multiple hydrogen-bonding interactions, because of their relatively weak, but directional, nature, are ideal for the strict self-assembly of closed spherical molecules and capsules. For example, component 10.49 consists of two intrinsically curved diphenylglycoluril units linked by a durene-based (1,2,4,5-tetramethyl benzene-based) spacer. In both solution and in the solid state, 10.49 self-assembles spontaneously to produce the tennis ball-shaped dimer (10.49)2 shown in Figure 10.43. The formation of the dimer has been observed by ... 

Professors Peter Aranyi and Julius Rebek have provided both the scientific discussions and the friendship without which Tamas Bartfai does not function. He acknowledges their insights and thanks for sustained support. 

A good fraction of modern chemistry, which includes medicinal chemistry, derives some of its inspiration from a consideration of nature as a model. It is impossible, in this brief article, to describe more than a fraction of the efforts. For additional work in the spirit of biomimetic chemistry, the following is a list of some authors not yet mentioned whose independent work should be consulted. Even here, this list is certainly not complete Jacqueline Barton, Steven Benkovic, Albrecht Berkessel, Thomas Bruice, Jik Chin, Jean Chmielewski, E. J. Corey, Donald Cram, Peter Dervan, Erancois Diederich, Mark Distefano, Jean Frechet, Samuel Gelhnan, John Groves, Andrew Hamilton, Donald Hilvert, Barbara Imperiali, Makoto Komiyama, Jean-Marie Lehn, Arthur Martell, Julius Rebek, Jean-Pierre Sauvage, Alanna Schepartz, Dieter Seebach, Donald Tomalia, and Steven Zimmerman. 

The geometry of the interactions of a carboxyl group has been investigated by Julius Rebek, He designed, prepared, and studied... 

Edward A. Wintner and Julius Rebek Jr Massachusetts Institute of Technology, Cambridge, MA, USA... 

REPRODUCED WITH PERMISSION FROM JULIUS REBEK, JAVIER SANTAMARIA, AND MICHAEL PIQUE... 

Each year there are interesting presentations that capture a unique niche and this year s perspective goes to Julius Rebek in which he describes a plethora of his adventures <04JOC2651> ranging from molecular devices, recognition, and encapsulation <040BC3051> it is always fun to review, briefly, the fullness of a researcher s modem history. 

Other scientists believe simpler hereditary systems originated before nucleic acids. In 1991, Julius Rebek was able to synthesize a simple organic molecule that replicates itself. According to his theory, this simple molecule may be the precursor of RNA. 

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