Bis(3-nitro-phen-yl) sulfone.

The asymmetric unit of the title compound, C(12)H(8)N(2)O(6)S, an important diphenyl sulfone derivative, contains one half-mol-ecule; a mirror plane passes through the SO(2) group. The dihedral angle between the two symmetry-related benzene rings is 40.10 (13)°.

Ethyl 2-{N-[N-(4-chloro-6-methoxy-pyrimidin-2-yl)carbamo-yl]sulfamo-yl}benzoate.

The asymmetric unit of the title compound, C(15)H(15)ClN(4)O(6)S, contains two independent mol-ecules, in which the pyrimidine and benzene rings are oriented at dihedral angles of 75.21 (3) and 86.00 (3)°.

N,N-Dimethyl-N'-[3-(trifluoro-methyl)-phenyl]-urea.

The title compound, C(10)H(11)F(3)N(2)O, is an important urea-based herbicide. In the crystal structure, the mol-ecular packing is stabilized by two intra-molecular C-H⋯O hydrogen bonds and one inter-molecular N-H⋯O hydrogen bond, generating a C(4) graph-set motif running parallel to the [001] direction. The F atoms are disordered over two sites, with occupancies of 0.

1-(2-Chloro-benzo-yl)-3-[4-(trifluoro-meth-oxy)phen-yl]urea.

The title compound, C(15)H(10)ClF(3)N(2)O(3), is considered to belong to a fourth generation of insecticides with properties such as high selectivity, low acute toxicity for mammals and high biological activity. The dihedral angle between the two benzene rings is 59.3 (2)°.

Bis(3-amino-phen-yl) sulfone acetonitrile solvate.

In the sulfone mol-ecule of the title compound, C(12)H(12)N(2)O(2)S·C(2)H(3)N, the two benzene rings are oriented at a dihedral angle of 80.69 (3)°. Weak intra-molecular C-H⋯O hydrogen bonds result in the formation of two five-membered rings, which both have envelope conformations.

Methyl 2-{[3-(4,6-dimethoxy-pyrimidin-2-yl)ureido]sulfonyl-meth-yl}benzoate.

In the title compound, C(16)H(18)N(4)O(7)S, a synthetic sulfonyl-urea herbicide, there are intra-molecular N-H⋯N and C-H⋯O hydrogen bonds. Inter-molecular N-H⋯O and C-H⋯O hydrogen bonds form centrosymmetric dimers. The dihedral angle between the two rings is 50.

Ethyl 4-{2,6-dichloro-4-[3-(2,6-difluoro-benzo-yl)ureido]phen-oxy}butanoate.

The title compound, C(20)H(18)Cl(2)F(2)N(2)O(5), is considered to belong to the fourth generation of insecticides with properties such as high selectivity, low acute toxicity for mammals and high biological activity. An intramolecular N-H⋯O hydrogen bond results in the formation of a six-membered ring. In the crystal structure, intermolecular N-H⋯O and C-H⋯F hydrogen bonds link the molecules.