Acridine, molecular structure

Both quinoline and isoquinoline molecular ions lose HCN to yield radical cation (109), while loss of HCN from acridine gives structure (110) (B-71MS364). 

Fig. 1 A. The absorption (-a-) and fluorescence (-o-) spectra of 9AAHH (5 x 10 3 M) in PVA film. The inset shows the molecular structure of 9-amino acridine. Panel (B) gives the fluorescence spectra of 9AAHH (5 x1c4 M) in spherical beads of PMMA with radius (a) 9 pm, (b) 3 pm and (c) 1.5 pm.

Acridine is a heterocyclic aromatic compound obtained from coal tar that is used in the syn thesis of dyes The molecular formula of acndine is C13H9N and its ring system is analogous to that of anthracene except that one CH group has been replaced by N The two most stable reso nance structures of acridine are equivalent to each other and both contain a pyndine like struc tural unit Wnte a structural formula for acridine... 

The molecular scaffolds also provide an unusual opportunity for the identification and recognition of meso structures. For example, successive acylation of L and D phenylalanine with the acridine diacid gives the structure 56 and we anticipate that... 

The chemistry of supramolecules forms an area of ever-increasing interest and application, arising from the extreme importance of such molecules, whether viewed in an academic or an applied perspective. Supramolecules are molecular assemblages, aggregates, or associations, and pyridine derivatives, particularly the bipyridines (84AHC281) and acridine, frequently play a key role in their construction and thus in their subsequent structure and behavior (95CRV2725). 

The crystal structure of acridine II, which contains two molecules in the asymmetric crystal unit, has been very carefully analysed by Phillips et al. (1960). Both molecules are significantly non-planar, the maximum deviation from the mean molecular plane being 0-041 A in one molecule and 0-014 A in the other. In one molecule the central ring tends towards a chair conformation and in the other towards a boat . These deviations are interpreted in terms of intermolecular interactions. 

With these issues in mind, dibenz[c,h]acridine was chosen as a spacer. As a result of its U-shape, chromophores attached at C-2 and C-12 could be held in parallel planes (Fig. 2). The C-2 to C-12 distance is known to be 7.24 A from the X-ray structure [23], however, the interchromophore distance in the molecular... 

Monocyclic azines are very weak --donors and behave mainly as n-donors on interaction with electrophiles. However, 7r-donor character is significantly increased in their benzo derivatives which have higher energy HOMOs (Table 2). For example, acridine 25 forms a highly colored 1 1 molecular complex with 2,3,5,6-tetrachloro-l,4-benzoquinone (chlor-anil). Perimidine 96 is one of the strongest heterocyclic --donors and gives deeply colored molecular complexes with a variety of organic electron acceptors. This is consistent with its electron-rich structure and its separate classification. 

Stezowski, J. J., Kollat, P., Bogucka-Ledochowska, M., and Glusker, J. P. Tau-tomerism and steric effects in l-nitro-9-(alkylamino)acridines (ledakrin or ni-tracrine analogues) probing structure-activity relationships at the molecular level. J. Amer. Chem. Soc. 107, 2067-2077 (1985). 

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