50739-80-5Relevant academic research and scientific papers
Water-induced fluorescence quenching of mono- and dicyanoanilines
Oshima, Juro,Yoshihara, Toshitada,Tobita, Seiji
, p. 306 - 311 (2008/02/13)
Photophysical properties of monocyano- (2-, 3-, and 4-cyano) and dicyano- (3,4-, 3,5-, 2,3-, 2,4-, 2,5-, and 2,6-dicyano) anilines are investigated by fluorescence measurements. All the monocyanoanilines are virtually nonfluorescent in water (quantum yield 0.01); however, in nonaqueous solvents (cyclohexane, acetonitrile and ethanol), the fluorescence quantum yield is enhanced substantially. In contrast, dicyanoanilines investigated are highly fluorescent both in aqueous and nonaqueous environments. The photophysical data and MO calculations suggest that conformational changes in the amino group and variation of hydrogen-bonding interactions between the solute and solvent water upon electronic excitation are responsible for the water quenching in the monocyanoanilines.
Antitumor imidazotetrazines. 32. Synthesis of novel imidazotetrazinones and related bicyclic heterocycles to probe the mode of action of the antitumor drug temozolomide
Clark,Deans,Stevens,Tisdale,Wheelhouse,Denny,Hartley
, p. 1493 - 1504 (2007/10/02)
A series of new imidazo[5,1-d]-1,2,3,5-tetrazinones with additional hydrogen-bonding or ionic substituents at the 8-carboxamide position of the antitumor drugs temozolomide (1) and mitozolomide (2) has been prepared. None of these compounds were significantly more cytotoxic in vitro against the mouse TLX5 lymphoma than the lead structures. Molecular modeling techniques have been used to design benzo- and pyrazolo[4,3-d]-1,2,3-triazinones bearing carboxamide groups in appropriate positions which are isosteric with temozolomide and mitozolomide but which cannot ring open to alkylating species. As predicted, these compounds have no inhibitory properties against human GM892A or Raji cell lines in vitro. Temozolomide and the spermidine- temozolomide conjugate 28 preferentially methylate guanines within guanine- rich sequences in DNA, but no experimental evidence has been found to support the hypothesis that such regions are involved in catalyzing the ring opening of the imidazotetrazinone prodrugs to their active forms.
