A new photochromic spiropyran of the indoline series, containing a quinoline fragment, has been synthesized. The photochromic properties of the spiropyran and its iodomethylate have been studied. Features of the molecular structure of the compounds were determined by X-ray structural investigations. It was established that the pyridopyran fragments of the cations in the crystal of the iodomethylate salt, unlike those in the crystal of the neutral spiropyran, emerge from 2 1 -stacks, disposed jointly with I -ions, which causes their higher mobility and aids the course of reversible photoconversions on UV irradiation in solution.Keywords: indolinospiropyran, quinoline fragment, X-ray structural analysis, photochromism.The synthesis of spiropyran salts (SP + X -), the investigation of their molecular, crystal structure, and photochromic conversions in the solid phase has caused immense interest [2][3][4][5][6][7] in the design of new polyfunctional materials based on them, combining in one crystal lattice several beneficial properties (photoswitching nonlinear optical properties [8] or photomagnetism [9]) and raising the prospect of using crystalline hybrids in miniature electronic instruments.Photochromic conversions of neutral spiropyrans, linked with cleavage of the C spiro -O bond and subsequent isomerization of the molecule, require a large open space and consequently is extremely hindered in crystals by the total packing in the lattice. As a rule the neutral spiropyrans in monocrystals and microcrystalline powders under stationary radiation conditions do not display photocoloration caused by the formation of open photomerocyanine structures [10], as was observed in solution or in the amorphous state.Investigation of ultrathin pressed microcrystalline samples of salts of spiropyrans and spiroxazines with N-methylated pyranopyridine rings [6,11,12] showed that at constant UV irradiation (365 nm) they are colored reversibly with the development of a broad absorption band between 500 and 650 nm, as was also observed in solution. The photochromic conversions are reversible and monocrystals survive some tens of cycles before structural and spectral changes. To establish the features of the molecular and crystal structure which provide reversible photochromic conversions of salts of spiropyrans under crystal packing conditions we carried out the synthesis and systemic investigation of the structure of new salts of various classes of spiropyrans [5,6,12,13].

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Novel series of photochromic indoline and benzoxazine spiropyrans containing ortho-placed formyl and hydroxyl groups in the benzene ring of the chromene part of the molecule have been prepared. X-ray analysis has shown that, depending on the structure of the heterocyclic component in the spiro cyclization reaction different, nonequivalent formyl groups of 2,4-dihydroxyisophthalaldehyde can participate. The synthesized compounds were used as original analogs of salicylaldehyde. The novel photochromic bispyropyrans prepared contain two different asymmetric spiro carbon atoms.The photochromic properties of spiropyrans are determined not only by a contribution from the heterene fragment but to a greater extent by the substituents in the 2H-chromene part of the molecule. We have prepared the novel spiropyrans 4 and 6 which are original analogs of salicylaldehyde. The spiropyrans 7 have been prepared from compound 4 and they contain two different spirocyclic centers and hence two asymmetric carbon atoms. The structures of the synthesized compounds 4, 6, 7 were confirmed by elemental analysis (Table 1) and by IR and 1 H NMR spectroscopy ( Table 2). The IR spectra of compounds 4, 6 show absorption bands at 1584-1633 and 912-996 cm -1 (ν C=C and ν C-O in the 2H-chromene fragment respectively) and in the spiropyrans 4 and 7 there are also carbonyl stretching bands from the benzoxazinone fragment at 1673-1686 cm -1 . In the IR spectra of the spiropyrans 4 and 6 the absorption bands for the formyl and hydroxyl groups are absent. Evidently this is connected with a strong intramolecular hydrogen bond (IHB). The 1 H NMR spectrum of compound 4a in deuterochloroform shows signals for the 3' and 4' protons as an AB-spectrum with δ (3') = 5.97 and δ (4') = 6.93 ppm (J 3'4' = 9.8 Hz). The N-CH 3 methyl group signal at position 3 of the oxazinone fragment, the formyl proton, and the OH proton placed ortho to it in the benzene ring of the 2H-chromene fragment appear as singlets at 3.17, 10.22, and 11.69 ppm respectively.In the indoline spiropyrans of series 6 the gem-dimethyl groups in position 3 are a convenient diastereotopic marker reflecting the spiropyran structure of the compound. The presence in the 1 H NMR spectrum of two singlet signals for the gem-dimethyl groups (gem (CH 3 ) 2 ) at δ = 1.15 and 1.25 ppm (in the case of compound 6a) is due to the presence in the molecule of an asymmetric carbon atom and confirms the _______ * For Communication 23 see [1]. __________________________________________________________________________________________

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Fused pyrimidine derivativesFused pyrimidine derivatives R 0515Synthesis of 3-Amino-1,2,3,4-tetrahydroquinazoline-2,4-dione. -The unexpected formation of title compound (II) by reaction of anthranilate (I) with hydrazine is reported. A reaction mechanism involving the intermediacy of a seven-membered heterocycle is proposed. -(MAKSIMENKO, A. A.; LUK'YANOV, B. S.; MAKSIMENKO, A. A.; ALEKSEENKO, Y. S.; Chem. Heterocycl. Compd. (N. Y.) 38 (2002) 6, 749-750; Inst. Phys. Org. Chem., Rostov State Univ., Rostov-on-Don 344104, Russia; Eng.) -M. Schroeter

Some spiropyrans containing functional substituents in the [2H]-chromene part of the molecule were synthesized and their photochromic properties in solution and solid state were investigated. The presence of the formyl group in the [2H]-chromene fragment enhances the possibility to show photochromic properties in solution.

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