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A new type of intramolecular cyclization of 1,5 bis[2 (E 3 oxo 3 phenylprop 1 enyl) phenoxy] 3 oxapentane with 3 aminotriazole promoted by potassium ions was discovered. A cascade mechanism for the formation of crownophane with 4,7 dihydro[1,2,4]triazolo[1,5 a] pyrimidine fragment was suggested. Effects of oligooxyethylene fragment of the chalcone podand and acid base catalysis on the selectivity of the cyclocondensation processes and degree of oxidation of triazolopyrimidine fragments were studied. The product structures were confirmed by IR, 1 H and 13 C NMR spectroscopy and X ray diffraction study.

Photoinduced transformations of 2 styrylquinazolinones in solutions were studied using absorption and NMR spectroscopy methods. A possibility of control of the photochemical isomerization rate of quinazolinone 2 (hydroxyaryl)ethenyl derivatives by changing the pH of the medium was demonstrated. The bases and the solvent nature also affect the luminescence intensity of solutions of these compounds in the wavelength range of 550-650 nm. The differ ences in the steric organization of the ortho hydroxystyryldiazinone system in crystals and in solutions related to the turn of the aryl group were found. Their influence on the competing processes of luminescence and photochemical transformation of the ethylene fragment were shown. The fact of reversible photo/thermal E-Z isomerization was established for (E) 2 (2 hydroxystyryl) 3 phenylquinazolin 4(3H) one.Key words: (E) 2 styrylquinazolin 4(3H) ones, ortho hydroxystyrylquinazolinones, lumi nescence, reversible photo/thermal isomerization, photoswitching.Diarylethenes and their heterocyclic analogues form the basis of modern electroluminescent and photochro mic materials, successfully used in nonlinear optics, lasers with tunable frequency, optoelectronic devices for record ing and storage of information, molecular photoswitch es. 1,2 Among hetarylstilbenes, their unsymmetric deriva tives 3,4 are of particular interest. Owing to the contribu tion of the n,* state, the presence of an acceptor azine (azinone) core in addition to the donor (aryl) one in stil bene molecules can have a considerable influence on photochemical and photophysical behavior of the lumi nophores. 5 However, there are fewer publications on the studies of the corresponding systems than of the symmetric (het)arylethenes. 4 In particular, there are several works on the synthesis of (E) 2 styrylquinazolin 4(3H) ones and the study of their photophysical properties. 4,6-10 It should be noted that compounds of this type with a specific emis sion ability and a tendency to a photoinduced E-Z iso merization 9,10 can be quite promising for the development of pH sensitive photochromic materials. We think that the introduction of a hydroxy group at the ortho position of the arylethenyl fragment of quinazolinones can gener ate photocontrolled processes related to the E-Z isomer ization with a proton transfer in the course of tautomeric transformations and heterocyclization to the correspond ing spiropyrans. ExperimentalIR spectra were recorded on a Perkin Elmer Spectrum One IR Fourier transform spectrometer using a diffuse reflectance sampling accessory (DRA). Electron absorption spectra were recorded on a UV 2401 PC double beam spectrophotometer (Shimadzu, Japan) in the range of 190-700 nm with the wave length setting accuracy of ±0.3 nm using a Shimadzu Scan stan dard program. Fluorescence spectra were recorded on a Varian Cary Eclipse fluorescence spectrophotometer with mutually per pendicular beams, the wavelength setting accuracy of 0.5 nm. The measurements were carried out in the range of 190-800 nm in SUP...

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