The title compound, C(28)H(28)N(2)O(5), consists of a partially hydrogenated acridine ring system with two substituted phenyl substituents on the dihydro-pyridine ring which are both nearly perpendicular to the mean plane of the acridine unit [dihedral angles of 81.3 (1) and 89.6 (1)° between the central ring of acridine and the methoxyphenyl and nitrophenyl rings, respectively]. The dihydro-py...

In the title compound, C(32)H(37)NO(3), the central dihydro-pyridine ring adopts a nearly planar flattened-boat conformation, whereas both cyclo-hexenone rings adopt half-chair conformations. The mean and maximum deviations from the mean plane of the dihydro-pyridine ring are 0.1252 (9) and 0.188 (1) Å, respectively. The 4-eth-oxy-phenyl and phenyl rings form dihedral angles of 75.20 (4) and 82...

In the title compound, C(18)H(15)NO(3), the pyridine-2,6-dione ring adopts an envelope conformation. The phenyl ring lies approximately perpendicular to the mean plane of the pyridine-2,6-dione ring [dihedral angle = 81.5 (1)°], while the methoxy-phenyl ring is tilted to the same plane by a dihedral angle of 34.8 (1)°. Inter-molecular C-H⋯O inter-actions link the mol-ecules into chains along [1...

In the title compound, C(22)H(12)Cl(2)N(4)O, the indole ring system and the benzene ring form dihedral angles of 21.18 (7)° and 68.43 (8)°, respectively, with the pyridine ring. The meth-oxy group is coplanar with the pyridine ring. In the crystal structure N-H⋯N inter-molecular hydrogen bonds link the mol-ecules into C(10) chains running along [011]. Intramolec-ular C-H⋯N hydrogen bonds are al...

The title compound, C(32)H(24)N(6)O(2), has an inversion centre located at the mid-point of the central C-C bond of the diether bridging unit. The terminal pyridine rings are canted relative to the central pyridine ring, with dihedral angles of 12.98 (6) and 26.80 (6)°. The maximum deviation from the eight-atom mean plane, defined by the two bridging O and C atoms and the central pyridine ring,...

In the title salt, C24H22N4O4 (2+)·2NO3 (-), the cation is U-shaped with the two iso-indole dione rings inclined to one another by 60.41 (13)°, while the two outer pyridine rings are inclined to one another by 2.77 (12)°. The dihedral angles between the pyridine ring and the adjacent iso-indole dione ring are 71.82 (12) and 86.44 (13)°. In the crystal, each nitrate anion is linked to a protonat...

In the title compound, C(28)H(32)N(2)O(7), the 1,4-dihydro-pyridine ring adopts a flattened boat conformation. The two benzene rings are approximately perpendicular to the dihydro-pyridine ring, forming dihedral angles of 84.29 (9) and 82.96 (9)° with the mean plane of the 1,4-dihydro-pyridine unit, whereas the ester groups are only slightly twisted relative to this plane, with dihedral angles ...

Substituted pyrido[3,2-d]pyrimidines are accessible by a reaction sequence consisting of HWE-reaction, Z/E-photoisomerization, and ring closure the pyridine ring. Bis-pyridopyrimidines can be obtained from 7-amino-pyrido[3,2-d]pyrimidines.

The title compound, C(15)H(22)BrN(3)O(2), consists of a pyridine ring with a bromine atom in the para position and two diethyl-amide groups in the ortho positions of the ring. Despite the positions of the three substituents on the pyridine ring, the mol-ecule does not exhibit either local or crystallographic twofold symmetry as the two diethyl-amido units exhibit significantly different N(py)-C...

The title compound, C(20)H(14)N(6)O(2), contains four rings. The dihedral angle between the pyridine ring and the pyrazole ring is 1.9 (1)°, i.e. almost coplanar, which gives rise to a conjugated structure. The dihedral angle between the nitro-substituted phenyl ring and the pyridine ring is 76.3 (1)° and that between the pyrazole ring and the non-substituted phenyl ring is 40.5 (1)°. In the cr...