Crystal structure, Hirshfeld surface analysis and DFT calculations of 7-bromo-2,3-di-hydro-pyrrolo[2,1-]quinazolin-9(1)-one.

The mol-ecular structure of the title compound, CHBrNO, is almost planar. The benzene and pyrimidine rings are essentially coplanar, with r.m.

Crystal structure and Hirshfeld surface analysis of bis-(6,7,8,9-tetra-hydro-11-pyrido[2,1-]quinazolin-5-ium) tetra-chlorido-zincate.

The title compound, (CHN)[ZnCl], is a salt with two symmetrically independent, essentially planar heterocyclic cations and a slightly distorted tetra-hedral chloro-zincate dianion. N-H⋯Cl hydrogen bonds link these ionic constituents into a discrete aggregate, which comprises one formula unit. The effect of hydrogen bonding is reflected in the minor distortions of the [ZnCl] moiety: distances between the cation and chlorido ligands engaged in classical hydrogen bonds are significantly longer than the others.

Structural insight from intermolecular interactions and energy framework analyses of 2-substituted 6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-ones.

The crystal structures of three mackinazolinone derivatives (2-amino-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-one at room temperature, and 2-nitro-6,7,8,9-tetrahydro-11H-pyrido[2,1-b]quinazolin-11-one and N-(11-oxo-6,8,9,11-tetrahydro-7H-pyrido[2,1-b]quinazolin-2-yl)benzamide at 100 K) are explored using X-ray crystallography. To delineate the different intermolecular interactions and the respective interaction energies in the crystal architectures, energy framework analyses were carried out using the CE-B3LYP/6-31G(d,p) method implemented in the CrystalExplorer software. In the structures the different molecules are linked by C-H.

()-6-(Furan-2-yl-methyl-idene)-6,7,8,9-tetra-hydro-pyrido[2,1-]quinazoline-11-thione.

A quinazolinthione, CHNOS, was synthesized by the condensation reaction of 6,7,8,9-tetra-hydro-11-pyrido[2,1-]quinazolin-11-thione with furfural. The mol-ecule crystallizes in the monoclinic system ( space group) and has an configuration with respect to the exocyclic C=C bond. In the crystal, mol-ecules are linked through C-H⋯π(furan) inter-actions, forming zigzag chains propagating along the [001] direction.

Synthesis of 2-(2-hydroxyethyl)-1-(2-hydroxyphenyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline and pseudosymmetry in its crystal structure.

Natural and synthetic isoquinoline alkaloids display a wide variety of potent biological activities. The title 1-aryl-2-hydroxyethyl-1,2,3,4-tetrahydroisoquinoline, C19H23NO4, crystallizes with two molecules in the asymmetric unit related by pseudo-translation but differing only slightly in conformation. The pseudosymmetry is also reflected in the diffraction pattern.

Crystal structure of 2,3-dimeth-oxy-5,6,7,8,13,13a-hexa-hydro-6a,8-di-aza-indeno-[2,1-b]phenanthrene methanol monosolvate.

The asymmetric unit of the title solvate, C21H22N2O2·CH3OH, contains one methanol solvent mol-ecule and one mol-ecule of the heterocycle that is built up by the fusion of four six-membered rings A, C, D, E and one five-membered ring B. The indole moiety (rings A and B) is essentially planar, with an r.m.

Crystal structure of anagyrine perchlorate.

The title mol-ecular salt, C15H21N2O(+)·ClO4 (-), crystallizes with four cations (A, B, C and D) and four anions in the chiral unit cell (space group P21). The alkaloid was isolated from the aerial parts of Genista Hispanica collected in the Samarkand region of Uzbekistan. Each cation is protonated at the N atom that bridges the alkaloid rings C and D.

2,3-Tri-methyl-ene-7,8-di-hydro-pyrrolo-[1,2-a]thieno[2,3-d]pyrimidin-4(6H)-one.

The title mol-ecule, C12H12N2OS, is planar, with an r.m.s.

(-)-Norfluoro-curarine ethanol monosolvate.

The title compound, C19H20N2O·C2H5OH, is an ethanol solvate of an indol alkaloid which was extracted from the plant Vinca erecta. The fused piperidine ring adopts an approximate boat conformation and the pyrrolidine ring an envelope conformation with one of the methyl-ene C atoms at the flap. An intra-molecular N-H⋯O hydrogen bond forms an S6 ring motif.

3-Methyl-2-(3,3,3-tri-chloro-2-hy-droxy-prop-yl)quinazolin-4(3H)-one.

The title mol-ecule, C12H11Cl3N2O2, contains planar quinazolin-4(3H)-one (r.m.s.

5,7-Dihy-droxy-2-(3-hy-droxy-4,5-dimeth-oxy-phen-yl)-6-meth-oxy-4H-chromen-4-one.

The title compound, C18H16O8, was isolated from the plant Artemisia baldshuanica Krasch et Zarp. The mol-ecule is approximately planar, with the exception of the terminal methyl groups, the C atoms of which devitate from their attached ring planes by 1.243 (5) and 1.

2,3-Dihydro-pyrrolo-[2,1-b]quinazoline-9(1H)-thione.

In the crystal, mol-ecules of the title compound, C(11)H(10)N(2)S, are connected by C-H⋯N inter-actions around threefold axes. Furthermore, they form stacks along the c axis showing π-π inter-actions between pyrimidine rings [centroid-centroid distance = 3.721 (1) Å].

Diaqua-dichloridobis[quinazolin-4(1H)-one-κN(3)]nickel(II).

In the title complex, [NiCl(2)(C(8)H(6)N(2)O)(2)(H(2)O)(2)], the Ni(II) ion is located on an inversion center and is six-coordinated by two N atoms of 1H-quinazolin-4-one ligands, two chloride ions and two water mol-ecules. The water mol-ecules are involved in intra- and inter-molecular O-H⋯O and O-H⋯Cl hydrogen bonding. Inter-molecular N-H⋯O and N-H⋯Cl hydrogen bonds are formed between ligands.

(4-Nitrophenyl)(1,2,3,9-tetrahydro-pyrrolo[2,1-b]quinazolin-3-yl)methanol monohydrate.

In the crystal structure of the title compound, C(18)H(17)N(3)O(3)·H(2)O, the mol-ecules are linked by O-H⋯O and O-H⋯N hydrogen bonds, resulting in a chain along the a axis. The crystal structure is stabilized by weak inter-molecular C-H⋯π (ring) hydrogen bonds and aromatic π⋯π stacking inter-actions [centroid-centroid distance = 3.902 (1) Å] between the pyrimidino rings of the quinazoline system.

2-Methyl-4-oxo-6,7,8,9-tetrahydro-thieno[2',3':4,5]pyrimidino-[1,2-a]pyridine-3-carboxylic acid.

There are two independent mol-ecules in the asymmetric unit of the title compound, C(12)H(12)N(2)O(3)S. With the exception of the methyl-ene groups, a mean plane fitted through all non-H atoms of each mol-ecule has an r.m.

Diaqua-dichloridobis[quinazolin-4(1H)-one-κN]copper(II).

In the title complex, [CuCl(2)(C(8)H(6)N(2)O)(2)(H(2)O)(2)], the Cu(II) ion is located on an inversion center and is octahedrally coordinated by two N atoms of the 1H-quinazolin-4-one ligand, two chloride ligands and two aqua ligands. The axial Cu-O distances are significantly longer [2.512 (2) Å], than the Cu-N [2.

(1-Phenyl-1H-1,2,3-triazol-4-yl)methyl pyridine-3-carboxyl-ate.

In the title compound, C(15)H(12)N(4)O(2), the dihedral angle between the planes of the nicotino-yloxy fragment and triazole ring is 88.61 (5)°. The dihedral angle between the planes of triazole and benzene rings is 16.

(E)-3-[4-(Dimethyl-amino)-benzyl-idene]-2,3-di-hydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one.

The title compound, C(20)H(19)N(3)O, was obtained by condensation of 2,3-dihydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one (alkaloid de-oxy-vasicinone, isolated from Peganum Harmala) with 4-(dimethyl-amino)-benzaldehyde in the presence of sodium methoxide. The 2,3-dihydro-1H,9H-pyrrolo-[2,1-b]quinazolin-9-one part of the mol-ecule is roughly planar (r.m.

11-(2-Oxopyrrolidin-1-ylmeth-yl)-1,2,3,4,5,6,11,11a-octa-hydro-pyrido[2,1-b]quinazolin-6-one dihydrate.

In the crystal structure of the title compound, C(17)H(21)N(3)O(2)·2H(2)O, water mol-ecules are mutually O-H⋯O hydrogen bonded and form infinite chains propagating along the b axis. Neighboring chains are linked by the quinazoline mol-ecules by means of O-H⋯O=C hydrogen bonds, forming a two-dimensional network.

9-Furfuryl-idene-2,3-dimethyl-6,7,8,9-tetrahydro-4H--thieno[2',3':4,5]pyrimidino[1,2-a]pyridin-4-one.

The title compound, C(17)H(16)N(2)O(2)S, was obtained by condensation of 2,3-dimethyl-thieno[2',3':4,5]pyrimidino[1,2-a]pyridin-4-one with furfural in the presence of sodium hydroxide. One of the methyl-ene groups of the tetra-hydro-pyrido ring is disordered over two positions in a 0.87 (1):0.

(E)-3-Propoxymethyl-idene-2,3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one monohydrate.

The title compound, C(15)H(16)N(2)O(2)·H(2)O, was synthesized via the alkyl-ation of 3-hydroxy-methyl-idene-2,3-dihydro-1H-pyrrolo[2,1-b]quinazolin-9-one with n-propyl iodide in the presence of sodium hydroxide. The organic mol-ecule and the water mol-ecule both lie on a crystallographic mirror plane. In the crystal structure, inter-molecular O-H⋯O and O-H⋯N hydrogen bonds link the components into extended chains along [100].

6,7,8,9,10,11-Hexahydro-13H-azocino[2,1-b]quinazolin-13-one.

The title compound, C(14)H(16)N(2)O, is a synthetic analogue of quinazolone alkaloids with pyrrilo, pyrido and azopino rings. The quinazolinic part of the mol-ecule is generally planar within 0.037 (3) Å; the eight-membered ring exhibits an inter-mediate conformation between the chair and boat forms as it is typical for cyclo-octene rings.

(1α,8β)-6β-Benzo-yloxy-6-dehydroxy-heteratisine from Aconitum zeravschanicum.

The title compound, C(29)H(37)NO(6), was isolated from Aconitum zeravschanicum and exhibits anti-arhythmic activity. It is a derivative of the diterpenoid alkaloid heteratisine and as such the core framework of the mol-ecule contains four six-membered, three seven-membered and one five-membered ring. The chair conformation of one of the meth-oxy-substituted six-membered rings is different from that observed in heteratisine hydro-bromide monohydrate.

8β-Acet-oxy-14α-benzo-yloxy-N-ethyl-3α,10β,13β,15α-tetra-hydr-oxy-1α,6α,16β-trimeth-oxy-4β-(methoxy-methyl-ene)aconitane: aconifine from Aconitum karakolicum Rapaics.

The title compound, C(34)H(47)NO(12), is the norditerpenoid alkaloid aconifine isolated from the leaves and tubers of Aconitum karakolicum Rapaics. It has a lycoctonine carbon skeleton and contains four six-membered rings and two five-membered rings; its geometry is similar to that observed in other lycoctonine-type diterpenoid alkaloids. There are two intra-molecular O-H⋯O hydrogen bonds which close five- and seven-membered pseudo-rings, respectively.

Synthesis, tautomeric states and crystal structure of (Z)-ethyl 2-cyano-2-(3H-quinazoline-4-ylidene) acetate and (Z)-ethyl 2-cyano-2-(2-methyl-3H-quinazoline-4-ylidene) acetate.

The new compounds (Z)-ethyl 2-cyano-2-(3H- and 2-methyl-3H-quinazoline-4-ylidene) acetate (1 and 2, respectively) were synthesized by multi-step reactions. The structures in a solution have been determined by (1)H-NMR spectroscopy and in the crystal form by X-ray analysis. Molecule 1 crystallized in a primitive monoclinic cell, space group capital ER, P2(1/c).