The title compound, C21H24O9, crystallizes with two independent mol-ecules in the asymmetric unit which are almost centrosymmetrically related to each other. The ethano-ate group in one of the two mol-ecules is disordered over two positions with a site-occupation factor of 0.880 (7) for the major occupied site. In the crystal, the 1,3-diketone group exists in the keto-enol isomeric form due to ...

In the crystal structure of a semi-synthetic opioid drug buprenorphine, C29H41NO4 {systematic name: (2S)-2-[(5R,6R,7R,14S)-9α-cyclo-propyl-methyl-3-hy-droxy-6-meth-oxy-4,5-ep-oxy-6,14-ethano-morphinan-7-yl]-3,3-di-methyl-butan-2-ol}, the cyclo-propyl-methyl group is disordered over two sites with an occupancy factor of 0.611 (3) for the major component. One of the hy-droxy groups is involved in...

In the title complex, [Co(C(6)H(14)NO(3))(N(3))] or [Co(teaH(2))N(3)], the Co(II) atom resides in a trigonal-bipymidal O(3)N(2) environment formed by three O atoms and one N atom from a simply deprotonated tetra-dentate triethano-lamine ligand, and one N atom from an azide ligand. The O atoms define the equatorial plane whereas both N atoms are in axial positions. The mononuclear units are link...

in order to increase the rate of gas absorption, chemical reaction in the liquid phase is considered. the purpose of this paper was to simulate gas absorption process by a liquid film over a spherical packing incorporating eddy viscosity and diffusivity. second order chemical reaction for two different cases (fast and slow) were considered. the system partial differential equations obtained was...

The melaminium (2,4,6-triamino-1,3,5-triazin-1-ium) cation in the title compound, C(3)H(7)N(6) (+)·C(3)H(3)O(4) (-), is essentially planar, with a r.m.s. deviation of the non-H atoms of 0.0085 Å. Extensive hydrogen bonding of the types N-H⋯N and N-H⋯O between cations and cations and between cations and hydrogen malonate (2-carb-oxy-ethano-ate) anions leads to the formation of supra-molecular la...

The title cholestan, C(28)H(46)O(3), was prepared by epoxidation of 7-norcholest-5-en-3β-yl acetate and crystallized by slow evaporation from an ethano-lic solution. All rings are trans fused. The 3β-acetate and the 17β-cholestane side chain are in equatorial positions. The mol-ecule is highly twisted due to its B-nor characteristic. A quantum chemical ab-initio Roothaan Hartree-Fock calculatio...

In the title compound, C(21)H(24)N(2)O(3), the mean planes of the benzene ring and the benzimidazole ring system form a dihedral angle of 69.94 (7)°. The ethyl group atoms of the ethano-ate fragment are disordered over two sets of sites, with refined occupancies of 0.742 (6) and 0.258 (6). In the crystal, there are weak C-H⋯N hydrogen bonds which connect mol-ecules into chains along the b axis....

Reaction of m-amino-benzoic acid (MABA), di-ethano-lamine (DEA) and MnCl2·4H2O led to the formation of the title salt, [Mn(C4H11NO2)2](C7H6NO2)2. In the complex cation, the Mn(2+) ion is located on an inversion centre and is coordinated by two symmetry-related tridentate DEA mol-ecules, leading to the formation of a slightly distorted MnN2O4 octa-hedron. The MABA(-) counter-anions are connected...