Molecular lock

Figure 3. Schematic representation of the concept of the molecular lock.

Figure 10.26 Cartoon representation of the formation of the Pt analogue of 10.16 from the uncatenated monomer by a molecular lock method.

The concept of a molecular lock using the dual character of a Pt(II)-pyridine coordination bond has been shown [95JA4175] utilization of the labile nature of the Pd(II)-pyridine bond has realized the quantitative self-assembly of [2]-catenane 27 from two related monocyclic counterparts. The catenane with M = Pd(II) is in rapid equilibrium whereas with M = Pt(II), the catenane is locked, but can be unlocked with added salt and heating or relocked by removing of the salt and cooling. 

Rasimas, J.P. Berglund, K.A. Blanchard, G.J. Molecular lock and key approach to detecting solution phase self assembly. A fluorescence and absorption study of carminic acid in aqueous glucose solutions. J. Phys. Chem. 1996, 100, (17) 7220-7229. 

Siegfried Z. and Cedar H. (1997). DNA methylation a molecular lock. Curr. Biol. 7 R305-R307. 

Ibukuro, F. Kusukawa. T. Fujita, M.A. Thermally switchable molecular lock. Guest-templated synthesis of a kinetically stable nanosized cage. J. Am. Chem. Soc. 1998, 120. 8561-8562. 

PQ2+. This molecular machine behaves as a molecular loop Later, the same group constructed another molecular lock, and shows a new way to construct CB-based molec- machine (Figure 47) based on reversible end-to-interior and... 

Almost all metal template-based syntheses of catenanes use Cu" ", but there are a few instances of other metal ion templates, including Zn +, Pd, and Pt +. The relative substitution-lability of Pd + makes it suitable as a preparative template the substitution-inertness of Pt + has been used as the basis for a temperature-switchable catenane molecular lock [257]. This mode of switching is based on platinum-nitrogen bond dissociation at elevated temperatures. 

Modelling binding sites. T ou have a two-dimensional molecular lock and key in solv ent 5, as show n in Figure 16.16. Different parts of each molecule have different chemical characters. A, B, or C. 

SCHEME 14.5 Molecular lock-and-key system based on the stereospecific change in conformation of a dynamic host. 

FICURE14.9 Stereospecific change in conformation of tris(terephthalamide) host (R,R,R) 12 upon complexation with a chiral ditopic guest (molecular lock-and-key system). 

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