3-Phenylaminoisoxazol-5(2H)-ones,s ubstituted on nitrogen with an isoquinoline or quinazoline group, react with tertiary amine bases to give imidazo annelated compounds. When the N-substituent is a nitropyridine, 2-aminoindole derivatives are formed instead. Evidence is presented that the reactions proceed by initial addition of the tertiary arnine to C-4

substituted 1, 2, 4- triazoles have shown multiple biological activities such as anti-inflammatory, anti fungal, etc. 5-mercapto triazoles were prepared from the potassium dithiocarbazinates. these triazoles were used for preparation of different derivatives by two different schemes. in the first scheme the mannich bases were prepared from 5- marcapto-s triazole quinazolines. the 5-marcato-s-tr...

From the ethyl acetate extract of the strain Streptomyces sp. isolate GW23/1540, besides 16 known products, several 1H-quinazolin-4-one derivatives were isolated. (SR)-2-(1-Hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (4) and (RR)-2-(1-hydroxyethyl)-2-methyl-2,3-dihydro-1H-quinazolin-4-one (5) are new natural products. 2-Methyl-3H-quinazolin-4-one (2) and 1H-quinazoline-2,4-dione (3) ...

The heterocyclic fused rings quinazoline and quinazolinone have drawn a huge consideration owing to their expanded applications in the field of pharmaceutical chemistry. Quinazoline and quinazolinone are reported for their diversified biological activities and compounds with different substitutions bring together to knowledge of a target with understanding of the molecule types that might inter...

In the title quinazoline derivative, C(21)H(17)N(3)O(2), the benzimidazole unit makes dihedral angles of 8.29 (5) and 81.79 (5)° with the benzene rings of the quinazoline and meth-oxy-phenol units, respectively. The nitro-gen-containing six-membered ring adopts a half-chair conformation. In the crystal, the mol-ecules are linked through O-H⋯N hydrogen bonds into screw chains along the b axis; a...

In the title compound, C(20)H(25)ClN(6) (2+)·2ClO(4) (-), the organic cation is roughly planar, as shown by the dihedral angle of 3.78 (3)° between the quinazoline and chloro-phenyl rings. The quinazoline ring is itself approximately planar, with an average deviation of 0.018 (4) Å. The organic cation adopts an E configuration with respect to the C= N double bond of the hyrazinyl group. The (di...

Synthesis of novel 5-methylidene-1,2,3,5-tetrahydro[2,1-b]-quinazoline derivatives 2-4 with potential biological activities mediated by alpha-adrenergic and/or imidazoline receptors was performed by reacting 2-chloro-4,5-dihydroimidazole (1) with the corresponding 2-aminoacetophenones. Compound 2, which incorporates an enamine moiety, underwent a 1,3-dipolar cycloaddition reaction with the appr...

In the crystal structure of the title two-dimensional network, [HgCl(2)(C(11)H(10)N(2)O)](n), the asymmetric unit consists of HgCl(2) dumbbells and one mol-ecule of the quinazoline unit. Pseudo-octa-hedrally coordinated Hg(II) cations are chloride-bridged via a crystallographic inversion centre leading to different Hg-Cl bonds (short and long) and linked by other Cl atoms via translation along ...

In the title compound, C(8)H(6)N(2)O(2), inter-molecular N-H⋯O hydrogen bonds involving the amine and carbonyl groups create centrosymmetric dimers between adjacent nearly coplanar mol-ecules. These dimers are further connected by weak N-H⋯O hydrogen bonds, forming a two-dimensional network. Mol-ecules are packed in the crystal structure with adjacent benzene and pyrimidine rings approximately ...

Racemic and optically active 3-(2-deuteriophenyl)-2-(1-phenylpropan-2-yl)quinazoline-4-thiones were prepared. The nuclear magnetic resonance spectra clearly show that they exist as a 1:1 mixture of diastereomers due to the isotopic atropisomerism based on ortho-H/D discrimination (N–C axial chirality) chiral carbon.