In the title compound, C(18)H(22)Cl(3)NO(11), a novel derivative of l-idopyran-osiduronic acid, the six-membered ring adopts a chair conformation.

In the title compound, C(9)H(11)NO(3), a derivative of salicyl-amide, the intra-cyclic C-C-C angles span the range 117.96 (13)-121.56 (14)°. An intra-molecular O-H⋯O hydro-gen bond occurs. In the crystal, inter-molecular O-H⋯O and N-H⋯O hydrogen bonds occur and C-H⋯O contacts connect the mol-ecules into a three-dimensional network. The closest inter-centroid distance between two π-systems is 3....

A nonlinear attitude model of a satellite with thrusters, gravity torquers and a reaction wheel cluster is developed. Then the linearized version of this satellite attitude model is derived for the attitude hold mode. For comparison purpose, various control methods are considered for attitude control of a satellite. We consider a proportional derivative controller which is actually used in the ...

The title mol-ecule, a benzohydrazide derivative, C(16)H(16)N(2)O(4), is twisted with a dihedral angle of 69.97 (5)° between the two benzene rings. An intra-molecular O-H⋯O hydrogen bond generates an S(5) ring motif. In the crystal, mol-ecules are linked by N-H⋯O and weak C-H⋯O hydrogen bonds into a chain along the c axis. C-H⋯π inter-actions are also present.

This communication shows the possibility of inducing spontaneous special surface organisation by means of grafting a fluorescent aminobenzo[g,h,i]perylene derivative onto surface grown polyacrylic chains.

In the title compound, C(16)H(14)O(4), a derivative of 2,2'-biphenol, the benzene rings are oriented at a dihedral angle of 58.32 (3)°.

The title mol-ecule, C(21)H(26)Br(2)O(2), is a substituted diphenyl-methane derivative whose angle at the methyl-ene carbon is 115.0 (2)°.

In the title compound, C(21)H(22)O, a derivative of the biologically active compound curcumin, the dihedral angle between the aromatic ring planes is 20.57 (11)°.

E. S. H . E l A shry*, L. F. A w ad, H. A bdel H am id , and Y. E l K ilany Chemistry Department, Faculty of Science, Alexandria University, Alexandria. Egypt * Reprint request to Prof. E. S. H. El Ashry. Fax: +20-3-4201360 Z. Naturforsch. 54b, 1061-1067 (1999); received April 12, 1999 D-Isoascorbic Acid, 6-Bromo-6-deoxyD-isoascorbic Acid, Pyridazine, Furo[3,2-c]pyridazine, Hepatitis B Virus Re...

The title compound, C 6 H 8 N 2 O 4 , a new derivative of isoxazole, has been synthesized and structurally characterized. crystal structure shows the molecule to be almost planar (r.m.s. deviation for non-hydrogen atoms = 0.029 Å), this conformation being supported by an intramolecular N—H...O hydrogen bond. In extended structure, molecules are linked bonds into chains propagating along [010].