Anilino Substituents Research Articles

Reactions of some 1,3-diaminonucleophiles with azlactones

Triethylamine-mediated reactions ofS-substituted isothiouronium halides (2) with unsaturated aziactones (1) gave the corresponding S-substituted 2-thiopyrimidines (3), S-substituted 3-thioacrylanilide (10), and 4-benzylidene-2-iminoimidazolidin-5-one (13), depending on the ethoxy, anilino, and phenyl substituents, respectively, at the 4-CC bond. Aminolyses of (3) afforded 2-aminopyrimidines (4). Tautomerism of compounds (3) and (13) was confirmed by their acetylation and/or hydrolysis. Basemediated condensation of compound (1c) with thiourea or urea in boiling ethanol was unsuccessful, but simple heating of these reactants at an elevated temperature gave 4-benzylidene-2-phenylimidazol-5(4H)-one (22).

Quantitative structure-activity relationships in cytokinin agonistic and antagonistic pyrido[2,3-d]pyrimidine derivatives: insights into receptor topology.

2-(Methylthio)pyrido[2,3-d]pyrimidines having various alkylamino and anilino substituents at the 4-position were prepared and tested for their cytokinin agonistic and antagonistic activities by the tobacco callus bioassay. The alkyl series of compounds showed anticytokinin activity, whereas the anilino derivatives exhibited both cytokinin and anticytokinin activities depending on the structure and position of the benzene substituents. Quantitative structure-activity analyses were carried out for each class and for the combined set of compounds with use of physicochemical parameters and regression analysis, indicating that the quality of activity, agonistic or antagonistic, as well as the extent of activity, is significantly affected by the steric features of the molecule. On the basis of the present results and previous quantitative analyses on cytokinins and other classes of anticytokinins, a dimensional map for the cytokinin receptor site can be drawn, which can serve as the basis for the design of novel agonists and antagonists.

Induction of petite formation in Saccharomyces cerevisiae by experimental antitumour agents : Structure—activity relationships for 9-anilinoacridines

A series of 9-anilinoacridine derivatives has been compared in terms of DNA binding, ability to inhibit the growth of L1210 murine leukaemia cells in vitro, and ability to induce the formation of respiration-deficient ( petite) mutations in Saccharomyces cerevisiae. The acridine ring in the derivatives was either unsubstituted, or substituted with amino groups at the 3 and/or 6 positions. The 9-anilino group was para-substituted with a variety of substituents. 3-Aminoacridine, 3,6-diaminoacridine (proflavine) and ethidium were included for comparison. The results show that: (i) at least one acridinyl amino group is necessary for conferring petite inducing activity in the yeast system; (ii) for 3-amino-9-anilinoacridine congeners, small anilino substituents provide compounds which resemble proflavine in their ability to produce petite mutants, whereas large substituents abolish activity; (iii) the 3,6-diamino-substituted anilinoacridines resemble ethidium rather than proflavine in being highly efficient inducers of petites; (iv) the requirements for optimal activity in L1210 leukaemia cell cultures are different to those for petite formation in yeast. It is concluded that the size of the anilino substituent, as well as its contribution to DNA binding, is critical in conferring biological activity in each system.

The crystal and molecular structure of 2-phenyl-4,5-dianilino-2H-1,2,3-triazole; correlation between the asymmetry of the triazole ring and the conformations of the anilino substituents

2-Phenyl-4,5-dianilino-2H-1,2,3-triazole, C20HIvNs, crystallizes in the monoclinic system, space group P2~, with Z = 2. At 23°C, a = 5.782 (1), b = 9.582 (1), c = 16.114 (1) A, f l= 106.15 (1) o, D x = 1.268, D m = 1.276 g cm -3. At 3 0 ° C , the temperature of the crystal during data collection, a = 5.758 (2), b = 9.570 (2), c = 16.035 (4) A, fl = 105.85 (3) ° . Intensities were obtained from 0-20 scans with a Syntex P2~ diffractometer using graphite-monochromated Mo K~t radiation. The structure was solved by direct methods. Full-matrix least-squares refinement of all positional and thermal (anisotropic for the non-hydrogen atoms and isotropic for the hydrogen atoms) parameters using 1398 reflections for which I > 2o(1) converged at a conventional R of 0.032. Although the molecule is symmetrically substituted with respect to the twofold axis, the triazole ring is found to be highly asymmetric. The chemically equivalent N N bond distances, 1.312 (2) and 1.379 (2) A, show the greatest disparity, although the C N distances, 1.350 (2) and 1.320 (2) A, are also significantly different. This distortion of the triazole ring is correlated via MINDO/3 calculations with the dissimilar conformations of the two anilino substituents, one of which is nearly coplanar with the triazole ring while the second is almost perpendicular to that ring.

Kristallstrukturanalyse von 4,6-Dianilino-2-phenylchinolin-5,8-chinon–CHCl3

The red-coloured dyestuff 4,6-dianilino-2-phenylquinoline-5,8-quinone (C27Ht9N302) crystallizes, with one molecule of CHCI 3, in the monoclinic space group P2~/a, with a = 12.412 (6), b = 23.695 (I0), c = 8.582 (4) A, fl = 93.67 (3) °, Z = 4. 4754 independent reflexions were measured on an automatic diffractometer using Cu K(ff radiation. The structure was solved by direct methods. All H atomic positions were obtained from a difference Fourier map. The least-squares refinement yielded a final R index of 0.055 for 3481 observed reflexions. The molecule contains two n-resonance systems, separated by C C single bonds, which include the N atoms of the anilino substituents of the quinolinequinone system. Two intramolecular hydrogen bridges are formed by the N H groups as donors and one C=O group as bivalent acceptor. The second C=O group forms a weak intermolecular hydrogen bridge with the H atom of CHCI~. The packing of the molecules is characterized by sheets of quinolinequinone parallel to the (010) plane with CHC13 molecules between them.