Catenane cartoons

Are there any other possible uses for the construction of complex topological species One possible application is in the mass production of DNA polyhedral catenanes by biological means, such as the polymerase chain reaction (PCR) (Saiki et al. 1986) or by production in vivo. Figure 21 illustrates that semi-conservative replication (the mechanism used by DNA polymerases) cannot reproduce a stable branch. The DNA with different sequences in the two arms of the branch (cartooned as dashed and solid lines) leads to two heterologous duplex DNA molecules, rather than a second branched molecule. 

Figure 7-46. A cartoon view of a catenane. The view emphasises that it is impossible to draw a catenane in two dimensions without a minimum of two points at which lines cross. The crossing points are indicated by arrows.

Figure 7-47. Two cartoon views showing the formation of a catenane from a difunctional molecular thread. The first view emphasises the approach that we discussed in Section 7.5. The second view emphasises the formation of the precursor and the catenane in terms of the number of crossing points which must be drawn in the molecular thread.

Figure 10.62 Cartoon and 2D molecular representation of pretzelane 10.88 and the alternative bis([2]catenane).66...

Fig. 4 Cartoons representing a [2]catenane and a [2]rotaxane. The arrows show the main possible large-amplitude movements of one component with respect to the other pirouetting (curved arrows) and shuttling (double-headed arrow)...

Fig. 16 Early examples of MIM cartoons, (a) Sauvage s cartoon of a [3]catenand [101]. (b) Synthetic scheme of a donor-acceptor [2]catenane that uses illustration to emphasize topology, noncovalent bonding, and electronic properties [102]. Reproduced with permission from [101] (copyright 1985 American Chemical Society), [102] (copyright 1991 Wiley-VCH)...

Fig. 18 presents a summary of the different ways to represent the same catenane. It is apparent that venturing into cartoons has opened space for much more freedom and creativity in the representation of molecules (note that every type of cartoon in Fig. 18e has been published in the chemical literature). We conclude that the transition to cartoons has been a boon in the field because cartoons ... 

Fig. 18 Different representations of the same donor-acceptor [2]catenane. Line drawings (a) and condensed structural formulas (b) were the order of the day until the modem era of MIMs gave way to structural diagrams (c) and crystal structures (d). Graphical representations, also called cartoons (e), can be a helpful compromise between these representations when attempting to emphasize the topology, noncovalent bonding interactions, shape, beauty, or function of a MIM...

Figure I Cartoons of the simplest rotaxane, catenane, and knot.

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