1-[(4-tert-Butyl­phen­yl)sulfon­yl]-1H-benzimidazole

The title compound, C17H18N2O2S, was synthesized by aryl­sulfonyl­ation of 1-hy­droxy­methyl-1H-benzimidazole in the presence of triethyl­amine. The benzimidazole and benzene rings form a dihedral angle of 84.1 (1)°. The tert-butyl group was treated as rotationally disordered over two orientations in a 0.51 (2):0.49 (2) ratio. In the crystal, weak inter­molecular C—H⋯O hydrogen bonds link the mol­ecules into chains propagating in [010]

2,3-Dimethylquinazolin-4(3H)-one

The non-H atoms of the title molecule, C10H10N2O, are essentially coplanar, with a maximum deviation of 0.046 (4) Å for the O atom. In the crystal, molecules are linked by weak C—H...O hydrogen bonds, forming chains along [010]. In addtion, weak C—H...π interactions and π–π stacking interactions between benzene and pyrimidine rings, with a centroid–centroid distance of 3.730 (3) Å, link the chains, forming a two-dimensional network parallel to (001)

N-(5-Benzylsulfanyl-1,3,4-thiadiazol-2-yl)-2-(piperidin-1-yl)acetamide

The title compound, C16H20N4OS2, was synthesized by the reaction of 2-benzylsulfanyl-5-chloroacetamido-1,3,4-thiadiazole and piperidine in a 1:2 ratio. The planes of the acetamide and 1,3,4-thiadiazole units are twisted by 10.8 (4)°. The thiadiazole S atom and the acetamide O atom are syn-oriented due to a hypervalent S...O interaction of 2.628 (4) Å. In the crystal, molecules form centrosymmetric dimers via N—H...N hydrogen bonds. These dimers are further connected by C—H...O interactions into (100) layers

Synthesis of Substituted Thieno[2,3-d]pyrimidin-4-ones and Their Testing for Evaluation of Cytotoxic Activity on Mammalian Cell Models

From 2-amino-3-ethoxycarbonyl-4,5-dimethyl-, -polymethylenethiophenes (1-4) were synthesized 2,3-disubstituted thieno[2,3-d]dihydropyrrolo-, tetrahydropyrido-, and tetrahydroazepino[1,2-a]pyrimidin-4-ones (5-16) for pharmacological investigations. The 12 compounds (5-16) were individually evaluated for their antiproliferative activities on mammalian cancer cell models. All tested compounds showed weak affection on human cervix adenocarcinoma cells (HeLa) whereas some of the tested compounds exhibited more consistent inhibition of cell growth on murine myeloma cells (P3X). In both cases some compounds enhanced cell proliferation

Thieno[2,3-d]Pyrimidin-4-Ones. Part 3.* Electrophilic Ipso-Substitution Reactions of Methyl and Methoxycarbonyl Groups

Interactions of 5,6-dimethyl- (1), 3,5,6-trimethylthieno[2,3-d]pyrimidin-4(3H)-ones (2) and 2,3-dimethyl- (5-7), 2-methyl-3-methoxycarbonylthieno[2,3-d]dihydropyrrolo-, - tetrahydropyrido-, tetrahydroazepino[1,2-a]pyrimidin-4-ones (14-16) with nitrating mixture were investigated. For the first time it is shown, that in dependence on the presence of substituent in position 2 and 3 of pyrimidine and thiophene rings reaction goes in various directions; by electrophilic ipso-substitution of methyl groups at C-5 by nitro group, or its oxidation up to carboxyl groups with formation corresponding 5-carboxy derivatives. It is revealed, that at absence of the substituent in position 3 (compound 1) the electrophilic ipso-substitution of methyl group by nitro group with formation of 5-nitro derivative took place. It is found, that at interaction of compounds 2,5-7, 14-16 with nitrating mixture instead of substitution of methyl groups at C-2, goes in an unexpected direction, i.e. there are oxidation of methyl groups or electrophilic ipso-substitution of methoxycarbonyl groups in position 3 by nitro group