In the title compound, [Fe(C5H5)(C34H28N3O)], the four-fused-rings system of the 11H-indeno-[1,2-b]quinoxaline unit is approximately planar [maximum deviation = 0.167 (4) Å] and forms a dihedral angle of 37.25 (6)° with the plane of the benzene ring of the methyl-benzoyl group. Both pyrrolidine rings adopt a twist conformation. An intra-molecular C-H⋯O hydrogen bond is observed. In the crystal,...

The asymmetric unit of title compound, C(18)H(16)O(2), contains two mol-ecules with slightly different conformations. In the first mol-ecule, the two phenyl rings make dihedral angles of 84.98 (11)° and the five-membered ring makes dihedral angles of 84.80 (12) and 73.00 (12)° with the phenyl rings; the corresponding angles for the second mol-ecule are 86.74 (11), 81.20 (13) and 71.36 (12)°. O-...

In the title Schiff base, C14H13NO4, which adopts the phenol-imine tautomeric form, the dihedral angle between the planes of the benzene and heterocyclic (r.m.s. deviation = 0.037 Å) rings is 53.31 (11)°. An intra-molecular O-H⋯N hydrogen bond closes an S(6) ring. In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds to generate C(11) chains propagating in the [010] direction. A weak C-...

There are two independent and conformationally dissimilar mol-ecules (A and B) in the asymmetric unit of the title compound, C11H6F3N3O3S; the dihedral angles between the benzene and thia-zole rings are 33.8 (2)° in A and 59.7 (2)° in B. The similarity of the C-N bond lengths in the amide group [1.379 (5) and 1.358 (5) Å for A, and 1.365 (5) and 1.363 (5) Å for B] indicates the presence of conj...

In the hydrazone mol-ecule of the title compound, C(15)H(12)ClN(3)O(4)·H(2)O, the two benzene rings form a dihedral angle of 3.6 (1)°. In the crystal structure, the solvent water mol-ecules are involved in the formation of inter-molecular N-H⋯O and O-H⋯N hydrogen bonds, which link the mol-ecules into double ribbons extending along the b axis. Inter-molecular π-π inter-actions between the aromat...

The title mol-ecule, C(21)H(15)NO, has an indoline-2-one and two benzene substituent groups which are arranged in a propeller-like fashion around the central C atom. The dihedral angle between the two benzene rings is 73.32 (16)° and those between the benzene rings and the indoline-2-one group are 76.54 (14) and 67.69 (14)°. In the crystal, there is an inter-molecular N-H⋯O hydrogen-bonding int...

The title compound, C24H30O7, is a diterpenoid isolated from the seeds of Caesalpinia minax. It consists of two cyclo-hexane rings (A and B), one unsaturated six-membered ring (C) and one furan ring (D). The stereochemistry of the ring junctures is A/B trans and B/C trans. Rings A and B have normal chair conformations while C adopts a twisted half-chair conformation due to fusion to the furan r...

The title compound, C(32)H(49)ClO(4), was obtained along with nitrile and lactam products in the POCl(3)-catalysed Beckmann rearrangement from 3β-acet-oxy-12-hydroxyiminoolean-28-olic acid methyl ester. The mechanism of the transformation leading to the title compound remains unclear and requires further investigation. Rings A, B and E are in chair conformations, ring C has a twisted-boat confo...

The concept of (A,B)-invariant subspace is the fundamental concept of the geometric approach of control design. It has been extended by many authors to that of (A,B)-invariant module or semimodule, for the sake of extending the solution of various control problems to the case of systems over rings or semi rings. In this paper is discussed the use of dynamic feedback control laws for systems ove...

let $r$ be an associative ring with identity and $z^*(r)$ be its set of non-zero zero divisors.  the zero-divisor graph of $r$, denoted by $gamma(r)$, is the graph whose vertices are the non-zero  zero-divisors of  $r$, and two distinct vertices $r$ and $s$ are adjacent if and only if $rs=0$ or $sr=0$.  in this paper, we bring some results about undirected zero-divisor graph of a monoid ring ov...