Band 24, Heft 5

Coumarin-benzothiazole hybrids are antitumor agents based on their antioxidant and α-glucosidase inhibitory activities. Compounds 5a–c were selected by National Cancer Institute (NCI), USA, to be screened for antitumor activity at a single dose (10 μ m ) against a panel of 60 cancer cell lines. The most active compound 5c was further screened at a five-dose level by NCI. Compound 5c displays half maximal growth inhibition (GI 50 ) values of 0.24 and 0.33 μ m against central nervous system (CNS) cancer (SNB-75) and ovarian cancer (OVCAR-4) cell lines, respectively. Compounds 5a–c were also screened for their antioxidant and α-glucosidase inhibitory activities.

Two new aza-acenequinone derivatives 4 and 5 were prepared by cyclocondensation of diamines 2 and 3 with bis(triisopropylsilyl)-dialkynyl-l,2-dione 1 . Further reactions of compounds 4 and 5 with malononitrile using the Lehnert reagent afforded corresponding tetracyanoquinodimethane (TCNQ) derivatives 6 and 7 . Compounds 4 , 6 and 7 were characterized by single crystal X-ray diffraction techniques. Compounds 6 and 7 were studied electrochemically and photochemically. Density functional theory (DFT) calculations on compounds 6 and 7 indicate that both compounds have the potential to be candidates for organic semiconductor materials.

A novel approach to the synthesis of 2-cyano-6-methoxybenzothiazole via the Cu-catalyzed cyanation of 2-iodo-6-methoxybenzothiazole was developed. K 4 [Fe(CN) 6 ] was used as a source of cyanide, and a Cu/N,N,N′,N′-tetramethylethylenediamine (TMEDA) system was utilized as a catalyst. This approach is scalable and can be practiced with operational benign. The most stable conformation of 2-cyano-6-methoxybenzothiazole was delineated using the density functional theory (DFT)/B3LYP method with 6-311++G(d, p) basis set.

4-(3-(Trifluoromethyl)benzylthio)phthalonitrile ( 1 ) was synthesized. Metal-free phthalocyanine 2 , zinc(II) phthalocyanine 3 and cobalt(II) phthalocyanine 4 were synthesized starting with dinitrile compound 1 . Photodynamic therapy properties of 2 and 3 were studied.

An efficient, practical approach to the copper-catalyzed synthesis of 2,3-disubstituted quinazolin-4(3 H )-one derivatives is described. The preparation involves treatment of benzyl amines with benzyl anthranilamides in the presence of Cu(OAc) 2 and tetra- n -butylammonium bromide (TBAB).

The mass spectrometric fragmentation of 6-(4-chlorophenyl)- N -aryl-4-(trichloromethyl)-4 H -1,3,5-oxadiazin-2-amines was studied under fast-atom bombardment (FAB) conditions. To simplify the interpretation of the mass spectra, a number of new 4 H -1,3,5-oxadiazine derivatives containing polyisotopic elements (Cl and Br) in the arylamine substituent were synthesized. It was shown that fragmentation occurs in two main patterns.

The synthesis of pyrazolo[3,4- f ]quinoline-8-carbonitriles 4a–h and 6a–k involves the reaction of an aromatic aldehyde, 1 H -indazol-6-amine and 3-(1 H -indol-3-yl)-3-oxopropanenitrile or 3-oxo-3-arylpropanenitrile in ethanol under mild conditions.

Synthesis of N -(5-methylisoxazol-3-yl)-2-(5-aryl-1,3,4-oxadiazol-2-yl)acetamides 5a–k was achieved from readily available materials. The compounds were screened for their in vitro antimicrobial activity against representative bacterial and fungal strains. Compounds 5b , 5d and 5f exhibit good activity.