Triazine interaction maps between

Figure 4. Benson plotter representation of interaction maps between a proton and DCMU (N-phenylureas), an s-triazine [2-chloro-4,6-bis(methylamino)-s-triazine], and an acylanilide [F -(3,4-...

Figure 5. Interaction maps between a proton and a triazinone [4-amino-6-phenyl-3-ethyl-l, 2,4-triazine-5(4H)-one], nitrofen (2,4-dichlorophenyl p-nitrophenyl ether), and a dinitrophenol (2-iso-propyl-4,6-dinitrophenol). For the latter compound, only two carbon atoms of the isopropyl group...

This also suggests that each triazine molecule can undergo hydrogen bonding with two sites. The N of the alkyamino groups are repulsive to the proton, whereas the N atom in position 5 on the ring is somewhat attractive. Nitrofen, which is not a DCMU-type inhibitor, presents a different case the molecule is somewhat twisted, so the interaction map depends upon the relative position between point charge and the nitrofen molecule. 

One of us has used molecular polarization potentials (MPP) to study the interaction of aromatic molecules, including furan, thiophene, and pyridine with a positive unitary charge, these maps being powerful tools for the study of intermolecular interactions and chemical reactivity [129,130], This kind of study leads us to examine theoretically the problem of the interaction between cations and anions with aromatic rings. We were pioneers in proposing that, in parallel with cation-7i-systems (for instance, benzene), there should exists anion-perfhiorinated-7i-systems (for instance, hexafluorobenzene) [131]. These studies include tetrafluorofuran and tetrafluorothiophene (128, 129). Simultaneously, Mascal et al. [132] described the same phenomenon but with 1,3,5-triazine (130) and 2,4,6-trifluoro-l,3,5-triazine (131) as acid 7i-systems. The group of the University of Palma de Mallorca has published a large number of papers on this topic [133] that are well summarized in a two recent reviews [134,135],... 

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