Janus molecules

Self-Assembly by Hydrogen-Bonding. Janus Molecules... 

Considering tridentate sites, 2,6-diaminopyridine and uracil are complementary single site groups (see Sections 9.4.2 and 9.4.3 below). On the other hand barbituric acid (BA) and 2,4,6-triaminopyrimidine (TAP) or -triazine (TAT) are Janus molecules containing two identical recognition sites while 168 is plerotopic by virtue of its two complementary sites (see Section 9.4.4). 

The so-called Janus molecules, which have the H-bonding sites of one face mirrored on the other face, were synthesized by the route shown in Scheme 4 (94TL397). 

Parks E and Trader MG (2000) Mechanisms of vitamin E regulation research over the past decade and focus on the future. Antioxidants and Redox Signaling 2,405-12. Rayman M (2000) The importance of selenium to human health. Lancet 356, 233-41. Rlcciarelli R, Zingg JM, andAzziA(2001) Vitamin E protective role of a Janus molecule. FASEB Journal 15,2314-25. 

RicciarelU R, Zingg JM, and Azzi A (2001) Vitamin E protective role of a Janus molecule. FASEB Journal 15,2314-25. 

N. Kimizuka, S. Fujikawa, H. Kuwahara, T. Kimitake, A. Marsh, J.M. Lehn, Mesoscopic Supramolecular Assembly of a Janus Molecule and a Melamine Derivative via Complementary Hydrogen-Bonds , J. Chem. Soc., Chem. Commun., 2103 (1995)... 

As previously noted, discrete assemblies based on 1-dimensional H-bonded motifs, also termed a-networks, may be obtained by covalently tethering the H-bonding recognition arrays or by their fusion to yield Janus molecules (Fig. 2). The information manifested in the relative orientation (120°) and juxtaposition of H-bonding donor/acceptor sites (DAD/ADA), in the specific case of 5 and 6, may generate three types of association a linear ribbon or tape, a H-bonded macrocycle and an intermediate wavy ribbon or crinkled tape [46]. These structures have been characterized in the solid state by X-ray crystallographic analysis. Homochiral crinkled tapes are formed in the course... 

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