K. Ramamurthi

Supramolecular architecture of bis­(melaminium) l‐tartrate 2.5‐hydrate

In the crystal structure of the title compound, 2C(3)H(7)N(6)(+) center dot C4H4O62- center dot 2.5H(2)O, the melaminium ions form infinite tapes via N-H center dot center dot center dot N hydrogen bonds. The tartrate anions, lying on twofold rotation axes, are arranged in linear arrays. The crystal packing is stabilized by an extensive net of hydrogen bonds leading to a supramolecular architecture.

16‐(3‐Pyridyl­methyl­ene)­androst‐4‐ene‐3,17‐dione

In the title compound, C25H29NO2, ring A adopts a slightly distorted half-chair conformation, while rings B and C are in chair conformations. The five-membered ring D adopts a 13β,14α-half-chair conformation. The 3-pyridyl ring has an E configuration with respect to the carbonyl group at position 17. The crystal structure is stabilized by weak intra- and intermolecular C—H⋯O interactions and van der Waals forces.

3-Nitrocinnamic acid

The title compound,

16-(2-Pyridylmethylene)androst-4-ene-3,17-dione

C_{9}H_{7}NO_{4}

4-(N,N-Di­methyl­amino­methyl­ene)-2-phenyl-2-oxazolin-5-one

, forms centrosymmetric dimers through intermolecular O-(HO)-O-... hydrogen bonds in the crystal structure.The nitro group deviates slightly from coplanarity with the benzene ring. The benzene ring and the carboxylic acid group are in an E configuration about the ethylenic double bond.

2‐Phenyl‐4‐(p‐toluidino­methyl­ene)‐5‐oxazolone

The title compound, C25H29NO2, crystallizes in the triclinic space group P1 with two crystallographically independent molxadecules in the unit cell. These two molxadecules differ in the orientation of the pyridyl rings with respect to the steroid nucleus, and also in the conformation of the five-membered rings.

3-[Chloro­(phen­yl)meth­yl]-6-methyl-1,2-benzoxazole

The title compound, C12H12N2O2, crystallizes in the triclinic space group Poverline 1 with two crystallographically independent molxadecules in the asymmetric unit. These two molxadecules differ slightly in the relative orientation of the phenyl and oxazoline rings. The molecular packing in the crystal is stabilized by C—H⋯O hydrogen bonds and van der Waals interactions.

4-[3-(1H-Imidazol-1-yl)prop-yl]-3-methyl-5-(thio-phen-2-ylmeth-yl)-4H-1,2,4-triazole monohydrate.

The two crystallographically independent molxadecules in the asymmetric unit of the title compound, C17H14N2O2, have nearly the same molecular geometry. The planarity of the oxazoline ring is not affected by substitutions at the 2 and 4 positions. The structure is stabilized by N—H⋯O type intermolecular interactions.

3β,17β‐Di­acetoxy‐16‐(2‐pyridyl­methyl­ene)androst‐5‐ene hydrate (1/0.46)

The title compound, C15H12ClNO, is a functionalized 1,2-benzoxazole with a chloro(phenyl)methyl substituent. The molecule is V-shaped, the dihedral angle between the mean plane of the 1,2-benzoxazole system [maximum deviation = 0.023u2005(3)u2005Å for the N atom] and the phenyl ring being 70.33u2005(14)°. There are no hydrogen-bonding interactions in the crystal structure, which is stabilized by van der Waals interactions only.

2‐(1H‐Indol‐3‐yl­methyl­ene)­indane‐1‐one

In the title compound, C14H17N5S·H2O, the triazole ring makes dihedral angles of 48.15u2005(8) and 84.92u2005(8)° with the imidazole and thiophenyl rings, respectively. The water molecule is involved in intermolecular O—H⋯N hydrogen bonding.