In the title compound, C(11)H(10)N(3)O(4)S(+)·C(2)F(3)O(2) (-), the benzene ring makes an angle of 87.3 (2)° with the pyridinium ring. The nitro group is essentially coplanar with the benzene ring. The F atoms of the CF(3) group are disordered over two positions with almost equal occupancy [0.531 (12)/0.469 (12)]. The crystal structure is stabilized by N-H⋯O and C-H⋯O hydrogen bonds.

In the title compound, C(29)H(19)F(2)NO(2), the central benzene ring forms a dihedral angle of 56.92 (12)° with the cyano-benzene ring and dihedral angles of 40.91 (12) and 44.76 (12)° with the two fluoro-benzene rings. In the crystal, C-H⋯O and C-H⋯F hydrogen bonds link the mol-ecules into sheets lying parallel to the ab plane. The crystal packing also features C-H⋯π inter-actions involving th...

The title compound, C(20)H(14)F(4)N(4), is a flexible bis-pyridine-type ligand with an extended fluorinated spacer group between the two pyridyl functions. The centroid of the central aromatic ring is situated on a crystallographic center of inversion. The dihedral angle between the pyridine ring and the central benzene ring is 63.85 (9)°. The crystal structure exhibits inter-molecular C-H⋯F hy...

Synthesis of adenosine triphosphate ATP, the 'biological energy currency', is accomplished by F(o)F(1)-ATP synthase. In the plasma membrane of Escherichia coli, proton-driven rotation of a ring of 10 c subunits in the F(o) motor powers catalysis in the F(1) motor. Although F(1) uses 120 degrees stepping during ATP synthesis, models of F(o) predict either an incremental rotation of c subunits in...

In the title compound, C(13)H(10)F(3)N(3)O(5), a derivative of andrographolide, the five-membered ring adopts an envelope conformation, while the non-planar six-membered ring has a chair conformation. An intra-molecular C-H⋯F hydrogen bond results in the formation of a non-planar six-membered ring adopting a twisted conformation. In the crystal structure, inter-molecular C-H⋯O hydrogen bonds li...

A synthesis of C17α-OH-tigogenin, the aglycon of aspafiliosides E and F, is described. The main features of the synthesis are three cascade processes, which involve the iodo-lactonization of furostan-26-acid to open ring E, a cascade hydrolysis/intramolecular SN2 process to close ring E, and a cascade intramolecular redox-ketalization process to close ring F. This synthesis would enrich the str...

The purpose of this note is to establish a number of useful results about the augmentation ideal J for the coefficient ring F ∗ G of a Noetherian complex orientable equivariant cohomology theory. The results show that various naturally occurring substitutes for the ideal have the same radical, and can therefore be used instead of the augmentation ideal in all geometric constructions. 1. Stateme...

in this paper, we study some ring theoretic properties of the amalgamated duplication ring $rbowtie i$ of a commutative noetherian ring $r$ along an ideal $i$ of $r$ which was introduced by d'anna and fontana. indeed, it is determined that when $rbowtie i$ satisfies serre's conditions $(r_n)$ and $(s_n)$, and when is a normal ring, a generalized cohen-macaulay ring and finally a filter ring.