Crystal structure of 2-benzyl-amino-4-p-tolyl-6,7-di-hydro-5H-cyclo-penta-[b]pyridine-3-carbo-nitrile.

The title compound, C23H21N3, comprises a 2-amino-3-cyano-pyridine ring fused with a cyclo-pentane ring. The later adopts an envelope conformation with the central methyl-ene C atom as the flap. The benzyl and and p-tolyl rings are inclined to one another by 56.18 (15)°, and to the pyridine ring by 81.87 (14) and 47.60 (11)°, respectively. In the crystal, mol-ecules are linked by pairs of N-H⋯Nnitrile hydrogen bonds, forming inversion dimers with an R 2 (2)(12) ring motif. The dimers are linked by C-H⋯π and π-π inter-actions [centroid-centroid distance = 3.7211 (12) Å], forming a three-dimensional framework.

Crystal structure of 1',1''-dimethyl-4'-(4-cholorophen-yl)di-spiro-[11H-indeno[1,2-b]quinoxaline-11,2'-pyrrolidine-3',3''-piperidin]-4''-one.

In the title compound, C30H27ClN4O, the central pyrrolidine ring adopts an envelope conformation with the methyl-ene C atom being the flap. The quinoxaline and indane rings are each essentially planar, with r.m.s. deviations of 0.027 (1) and 0.0417 (1) Å, respectively. The pyrrolidine ring forms dihedral angles of 88.25 (1) and 83.76 (1)° with the quinoxaline and indane rings, respectively. A weak intra-molecular C-H⋯N inter-action is observed. In the crystal, C-H⋯π inter-actions lead to supra-molecular chains along [101] that assemble in the ac plane. Connections along the b axis are of the type Cl⋯Cl [3.6538 (16) Å].

Crystal structure of 2-benzyl-amino-4-(4-bromo-phen-yl)-6,7-di-hydro-5H-cyclo-penta-[b]pyridine-3-carbo-nitrile.

In the title compound C22H18BrN3, the cyclo-pentane ring adopts an envelope conformation with the central methyl-ene C atom as the flap. The dihedral angles between the central pyridine ring and the pendant benzyl and and bromo-benzene rings are 82.65 (1) and 47.23 (1)°, respectively. In the crystal, inversion dimers linked by pairs of N-H⋯Nn (n = nitrile) hydrogen bonds generate R 2 (2)(12) loops. These dimers are linked by weak π-π inter-actions [centroid-centroid distance = 3.7713 (14) Å] into a layered structure.

Crystal structures of 2-benzyl-amino-4-(4-bromo-phen-yl)-6,7,8,9-tetra-hydro-5H-cyclo-hepta-[b]pyridine-3-carbo-nitrile and 2-benzyl-amino-4-(4-chloro-phen-yl)-6,7,8,9-tetra-hydro-5H-cyclo-hepta[b]pyridine-3-carbo-nitrile.

In the title compounds, C24H22BrN3, (I), and C24H22ClN3, (II), the 2-amino-pyridine ring is fused with a cyclo-heptane ring, which adopts a half-chair conformation. The planes of the phenyl and benzene rings are inclined to that of the central pyridine ring [r.m.s. deviations = 0.0083 (1) and 0.0093 (1) Šfor (I) and (II), respectively] by 62.47 (17) and 72.51 (14)°, respectively, in (I), and by 71.44 (9) and 54.90 (8)°, respectively, in (II). The planes of the aromatic rings are inclined to one another by 53.82 (17)° in (I) and by 58.04 (9)° in (II). In the crystals of both (I) and (II), pairs of N-H⋯Nnitrile hydrogen bonds link the mol-ecules, forming inversion dimers with R 2 (2)(12) ring motifs. In (I), the resulting dimers are connected through C-H⋯Br hydrogen bonds, forming sheets parallel to (10-1), and π-π inter-actions [inter-centroid distance = 3.7821 (16) Å] involving inversion-related pyridine rings, forming a three-dimensional network. In (II), the resulting dimers are connected through π-π inter-actions [inter-centroid distance = 3.771 (2) Å] involving inversion-related pyridine rings, forming a two-dimensional network lying parallel to (001).

Crystal structure of 1-benzyl-4-(4-chloro-phen-yl)-2-imino-1,2,5,6,7,8,9,10-octa-hydro-cyclo-octa-[b]pyridine-3-carbo-nitrile.

The title compound, C25H24ClN3, comprises a 2-imino-pyridine ring fused with a cyclo-octane ring, which adopts a twist boat-chair conformation. In the crystal, C-H⋯N inter-actions form R 2 (2)(14) ring motifs and mol-ecules are further connected by weak C-H⋯π inter-actions. The resulting supra-molecular structure is a two-dimensional framework parallel to the ab plane.

Isotypic crystal structures of 1-benzyl-4-(4-bromo-phen-yl)-2-imino-1,2,5,6,7,8,9,10-octa-hydro-cyclo-octa-[b]pyridine-3-carbo-nitrile and 1-benzyl-4-(4-fluoro-phen-yl)-2-imino-1,2,5,6,7,8,9,10-octa-hydro-cyclo-octa-[b]pyridine-3-carbo-nitrile.

The mol-ecules of the two isotypic title compounds, C25H24BrN3, (I), and C25H24FN3, (II), comprise a 2-imino-pyridine ring fused with a cyclo-octane ring. In (I), the cyclo-octane ring adopts a twisted chair-chair conformation, while in (II), this ring adopts a twisted boat-chair conformation. The dihedral angles between the planes of the pyridine ring and the bromo-benzene and phenyl rings are 80.14 (12) and 71.72 (13)°, respectively, in (I). The equivalent angles in (II) are 75.25 (8) and 68.34 (9)°, respectively. In both crystals, inversion dimers linked by pairs of C-H⋯N inter-actions generate R 2 (2)(14) loops, which are further connected by weak C-H⋯π inter-actions, generating (110) sheets.

Crystal structure of 1-benzyl-4-(2,4-di-chloro-phenyl)-2-imino-1,2,5,6,7,8,9,10-octa-hydro-cyclo-octa-[b]pyridine-3-carbo-nitrile.

In the title compound, C25H23Cl2N3, the cyclo-octene ring adopts a twist chair-chair conformation. The dihedral angles between the central pyridine ring (r.m.s. deviation = 0.013 Å) and the pendant chloro-benzene and benzyl rings are 78.07 (11) and 87.47 (12)°, respectively. No directional inter-actions could be identified in the crystal and the packing is governed by van der Waals inter-actions.

Crystal structure of 5-amino-5'-chloro-6-(4-chloro-benzo-yl)-8-nitro-2,3-di-hydro-1H-spiro-[imidazo[1,2-a]pyridine-7,3'-indolin]-2'-one including an unknown solvent mol-ecule.

The asymmetric unit of the title compound, C21H15Cl2N5O4, contains two independent mol-ecules (A and B) having similar conformations. The amine (NH2) group forms an intra-molecular hydrogen bond with the benzoyl group, giving an S(6) ring motif in both mol-ecules. The central six-membered rings adopt sofa conformations and the imidazole rings are planar (r.m.s deviations = 0.0150 and 0.0166 Å). The pyridine and imidazole rings are inclined to one another by 3.54 (1) and 3.03 (1)° in mol-ecules A and B, respectively. In the crystal, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains along the a axis which enclose R 2 (2)(16) ring motifs. The rings are linked by weak N-H⋯O and C-H⋯O hydrogen bonds and C-H⋯π inter-actions forming sheets lying parallel to (001). A region of disordered electron density, most probably disordered solvent mol-ecules, occupying voids of ca 753 Å(3) for an electron count of 260, was treated using the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. Their formula mass and unit-cell characteristics were not taken into account during refinement.

5-Amino-5'-bromo-6-(4-methyl-benzo-yl)-8-nitro-2,3-di-hydro-1H-spiro-[imidazo[1,2-a]pyridine-7,3'-indolin]-2'-one including an unknown solvate.

In the title compound, C22H18BrN5O4, the central six-membered ring, derived from 1,4-di-hydro-pyridine, adopts a distorted boat conformation with a puckering amplitude of 0.197 (3) Å, the imidazole ring adopts a twisted conformation with a puckering amplitude of 0.113 (3) Å, and the oxindole moiety is planar with an r.m.s. deviation of 0.0125 Å. Two intra-molecular N-H⋯O hydrogen bonds are formed, each closing an S(6) loop. In the crystal, strong N-H⋯O hydrogen bonds lead to the formation of zigzag chains along the c axis. These are consolidated in the three-dimensional crystal packing by weak N-H⋯O hydrogen bonding, as well as by C-H⋯O, C-H⋯Br and C-H⋯π inter-actions. A small region of electron density well removed from the main mol-ecule was removed with the SQUEEZE procedure in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155] following unsuccessful attempts to model it as a plausible solvent mol-ecule. The unit-cell characteristics do not take into account this feature of the structure.

5-Amino-6-benzoyl-8-nitro-2,3-di-hydro-1H-spiro-[imidazo[1,2-a]pyridine-7,3'-indolin]-2'-one dimethyl sulfoxide monosolvate.

In the title compound C21H17N5O4·C2H6OS, the central six-membered ring derived from 1,4-di-hydro-pyridine adopts a distorted boat conformation with a small puckering amplitude of 0.127 (3) Å. The sums of bond angles around the pyridine N atom [358.7 (2)°] and the other imidazolidine N atom [60 (2)°] indicate that these atoms are in sp(2) hybridization, leading to an essentially planar imidazolidine ring. The last heterocycle, an oxindole moiety, is also nearly planar with an r.m.s. deviation of 0.0185 (1) Å. The amine NH2 group forms an intra-molecular hydrogen bond with the benzoyl group, giving a S(6) motif. In the crystal, N-H⋯O hydrogen bonds lead to the formation of chains along the c-axis direction. Within the chains there are further N-H⋯O and C-H⋯O hydrogen bonds enclosing R (2) 2(14) ring motifs. The chains are linked via N-H⋯O and C-H⋯O hydrogen bonds involving the dimethyl sulfoxide solvent mol-ecule which acts as both an acceptor and a donor..

(3aR*,8bR*)-3a,8b-Dihy-droxy-1-(4-methyl-phen-yl)-2-methyl-sulfanyl-3-nitro-1,8b-di-hydro-indeno-[1,2-b]pyrrol-4(3aH)-one.

The asymmetric unit of the title compound, C19H16N2O5S, contains four independent mol-ecules (A, B, C and D), with two mol-ecules (B and D) displaying disorder in their methyl-sulfanyl groups [occupancy ratios of 0.797 (11):0.203 (11) and 0.85 (2):0.15 (2)]. The nitro groups are twisted slightly out of the planes of the 2-pyrroline rings to which they are bonded with dihedral angles of 10.17 (1), 8.01 (1), 9.44 (1) and 8.87 (1)° in mol-ecules A, B, C and D, respectively. The 2-pyrroline rings are almost orthogonal to the attached tolyl rings, forming dihedral angles of 73.44 (1), 81.21 (1), 88.18 (8) and 73.94 (1)° for mol-ecules A, B, C and D, respectively. A weak intra-molecular O-H⋯O inter-action is observed in mol-ecules B and C. The two hy-droxy groups in each mol-ecule are involved in inter-molecular O-H⋯O hydrogen bonding. In the crystal, mol-ecules are connected via O-H⋯O and C-H⋯O hydrogen bonds, forming a complex three-dimensional network.

10-(4-Chloro-phen-yl)-14a-hy-droxy-12-methyl-8,9,9a,10,12,13,14,14a-octa-hydro-5H-10a,14-methano-indeno-[2',1':4,5]azepino[3,4-b]pyrrolizine-5,15(7H,11H)-dione.

The asymmetric unit of the title compound, C26H25ClN2O3, contains two independent mol-ecules (A and B). The conformation of the two mol-ecules differs essentially in the dihedral angle involving the two benzene rings. They are inclined to one another by 52.47 (10) in A and by 31.75 (11)° in B. In both mol-ecules, the six-membered piperidin-3-one rings have chair conformations. In mol-ecule A, all four five-membered rings have twist conformations. In mol-ecule B, only three of the four five-membered rings have twist conformations. The fourth, of the inden-1-one moiety, has an envelope conformation with the spiro C atom, bonded to the N atom of the pyrrolidine ring, as the flap. A weak intra-molecular O-H⋯N hydrogen bond occurs in each independent mol-ecule while a C-H⋯O inter-action is also observed in mol-ecule A. In the crystal, pairs of O-H⋯O hydrogen bonds link the mol-ecules, forming inversion dimers with graph-set motif R 2 (2)(12). These dimers are further inter-connected by C-H⋯O and C-H⋯π inter-actions, forming a three-dimensional network.

Crystal structure of 2-benzyl-amino-4-(4-meth-oxy-phen-yl)-6,7,8,9-tetra-hydro-5H-cyclo-hepta-[b]pyridine-3-carbo-nitrile.

The title compound, C25H25N3O, comprises a 2-amino-pyridine ring fused with a cyclo-heptane ring, which adopts a chair conformation. The central pyridine ring (r.m.s. deviation = 0.013 Å) carries three substituents, viz. a benzyl-amino group, a meth-oxy-phenyl ring and a carbo-nitrile group. The N atom of the carbo-nitrile group is significantly displaced [by 0.2247 (1) Å] from the plane of the pyridine ring, probably due to steric crowding involving the adjacent substituents. The phenyl and benzene rings are inclined to one another by 58.91 (7)° and to the pyridine ring by 76.68 (7) and 49.80 (6)°, respectively. In the crystal, inversion dimers linked by pairs of N-H⋯Nnitrile hydrogen bonds generate R 2 (2)(14) loops. The dimers are linked by C-H⋯π and slipped parallel π-π inter-actions [centroid-centroid distance = 3.6532 (3) Å] into a three-dimensional structure.

1''-Allyl-5''-(4-meth-oxy-benzyl-idene)-7'-(4-methoxy-phen-yl)-1',3',5',6',7',7a'-hexa-hydro-dispiro-[ace-naphthyl-ene-1,5'-pyrrolo-[1,2-c][1,3]thia-zole-6',3''-piperidine]-2,4''(1H)-dione.

In the title compound, C39H36N2O4S, the piperidine ring adopts a twisted half-chair conformation. In the pyrrolo-thia-zole fused-ring system, the pyrrole ring adopts an envelope conformation (with the C atom bound to the thia-zole ring being the flap atom) and the thia-zole ring also exhibits an envelope conformation (with the N atom bound to the pyrrole ring as the flap). The mol-ecular structure features a weak intra-molecular C-H⋯O inter-action. In the crystal, a C-H⋯O inter-action forms a linear chain along the diagonal of the ac plane, generating a C(14) graph-set motif. A weak C-H⋯π inter-action also occurs.

14a-Hy-droxy-12-methyl-10-(4-methyl-phen-yl)-8,9,9a,10,12,13,14,14a-octa-hydro-10a,14-methano-5H-indeno-[2',1':4,5]azepino[3,4-b]pyrrolizine-5,15(7H,11H)-dione.

In the title compound, C27H28N2O3, each of the pyrrolidine rings adopts a twisted conformation, as does the cyclo-pentane ring. The indane ring has an r.m.s deviation of 0.0693 Å. The dihedral angle between the mean plane of the pyrrolizine ring and indane system is 82.58 (1)°. The piperidine ring has the methyl substituent in an equatorial position and adopts a twisted chair conformation. The mol-ecular structure is stabilized by a weak intra-molecular O-H⋯N inter-action.

rac-5''-(4-Fluoro-benzyl-idene)-1'-(4-fluoro-phen-yl)-1''-methyl-1',2',3',5',6',7',8',8a'-octa-hydro-dispiro-[acenaphthyl-ene-1,3'-indolizine-2',3''-piperidine]-2,4''(1H)-dione.

In the title E isomer of the racemic compound, C37H32F2N2O2, the pyridinone ring adopts a twisted half-chair conformation with the N atom deviating by -0.355 (3) Šand with the methyl-ene C atom next to octa-hydro-indolizine moiety deviating by 0.415 (3) Šfrom the mean plane defined by other four atoms. In the octa-hydro-indolizine system, the pyrrolidine ring exhibits an envelope conformation with the fused methyne C atom deviating by 0.6496 (1) Šfrom the mean plane defined by four other atoms, and the piperidine ring exhibits a distorted chair conformation as evident from the puckering parameters Q = 0.568 (2) Å, θ = 1.0 (2) and Φ = 256 (11)°. In the crystal, C-H⋯O inter-actions connect the mol-ecules into chains along [101].

5''-(4-Meth-oxy-benzyl-idene)-1'-(4-meth-oxy-phen-yl)-1''-methyl-1',2',3',5',6',7',8',8a'-octa-hydro-dispiro-[acenaphthyl-ene-1,3'-indolizine-2',3''-piperidine]-2,4''(1H)-dione.

In the title compound, C(39)H(38)N(2)O(4), the pyridinone ring adopts a twisted half-chair conformation with the N atom deviating by 0.3304 (1) and with the methyl-ene C atom adjacent to the octa-hydro-indolizine unit deviating by 0.444 (3) Šfrom the mean plane defined by the other four atoms. In the octa-hydro-indolizine system, the pyrrolidine ring exhibits an envelope conformation, with the fused methyne C atom deviating by 0.6315 (1) Šfrom the mean plane defined by the other four atoms, and the piperidine ring exhibits a distorted chair conformation, as reflected in the puckering parameters Q = 0.568 (4) Å, θ = 1.5 (4) and ϕ = 161 (16)°. In the crystal pairs of weak C-H⋯O inter-actions form centrosymmetric dimers, which are further connected by C-H⋯π inter-actions. The crystal studied was a non-merohedral twin, with a domain ratio of 0.91:0.09.

1',1''-Dimethyl-4'-phenyl-dispiro-[11H-indeno-[1,2-b]quinoxaline-11,2'-pyrrolidine-3',3''-piperidin]-4''-one.

In the title compound, C30H28N4O, the central pyrrolidine ring adopts an envelope conformation with the CH2 C atom as the flap. The quinoxaline and indene ring systems are planar, with r.m.s. deviations of 0.0165 and 0.0181 Å, respectively. The pyrrolidine ring mean plane forms dihedral angles of 88.84 (1) and 86.14 (1)° with the quinoxaline and indene ring systems, respectively. A weak intra-molecular C-H⋯N inter-action is observed. In the crystal, C-H⋯O inter-actions lead to helical supra-molecular chains along the b axis having a C(9) motif.

1',1''-Dimethyl-4'-(4-methyl-phen-yl)di-spiro-[11H-indeno-[1,2-b]quinoxaline-11,2'-pyrrolidine-3',3''-piperidin]-4''-one.

In the title compound, C31H30N4O, the central pyrrolidine ring adopts an envelope conformation with the methyl-ene C atom being the flap. The quinoxaline and indane rings are each planar, having r.m.s. deviations of 0.030 and 0.050 Å, respectively. The pyrrolidine ring mean plane forms dihedral angles of 88.25 (1) and 83.76 (1)° with the quinoxaline and indane rings, respectively. Intra-molecular C-H⋯O and C-H⋯N inter-actions are observed. In the crystal, C-H⋯π inter-actions lead to helical supra-molecular chains along the b-axis direction.

(3aR,8bR)-3a,8b-Dihy-droxy-2-methyl-sulfanyl-3-nitro-1-phenyl-1,8b-di-hydro-indeno[1,2-b]pyrrol-4(3aH)-one.

In the title compound, C18H14N2O5, the pyrrolidine ring adopts a shallow envelope conformation, with the C atom bearing the OH group (and remote from the N atom) displaced by 0.257 (2) Šfrom the other atoms. The cyclo-pentane ring has a twisted conformation about the C-C bond bearing one =O and one -OH grouping. The dihedral angle between the five-membered rings (all atoms) is 65.54 (9)° and the OH groups lie to the same side of the ring-junction. The mol-ecular structure features a weak intra-molecular O-H⋯O bond and a possible C-H⋯π inter-action. In the crystal, the mol-ecules are linked into [010] chains by O-H⋯O hydrogen bonds. Weak C-H⋯O bonds connect the chains into (100) sheets.