Synthesis, chemical characterization, structural data and solid state behaviour of N, N′-diethyl-1, 2-ethanediamine complexes of nickel(II) thiocyanate

The physical and chemical characterization of the solid-state properties of drugs and excipients is fundamental for planning new formulations and developing new strategies for the treatment of diseases. Techniques such as differential scanning calorimetry, thermogravimetry, X-ray powder diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy are among the most commonly used techniques for these purposes. Penciclovir and lysine are individually used to treat the herpes virus. As such, the development of a formulation containing both drugs may have therapeutic potential. Solid-state characterization showed that both penciclovir and lysine were crystalline materials with melting points at 278.27 °C and 260.91 °C, respectively. Compatibility studies of penciclovir and lysine indicated a possible interaction between these substances, as evidenced by a single melting point at 253.10 °C. The compatibility of several excipients, including ethylenediaminetetraacetic acid, cetostearyl alcohol, sodium lauryl sulphate, di-tert-butyl methyl phenol, liquid petrolatum, methylparaben, nonionic wax, paraffin, propylene glycol, and propylparaben, was evaluated in ternary (penciclovir-lysine-excipient) mixtures (1:1:1, w/w/w) to determine the optimal formulation. The developed formulation was stable under accelerated and ambient conditions, which demonstrated that the interaction between penciclovir and lysine was suitable for the development of a formulation containing both drugs.

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Linear Chain Bis(α,β-dionedioximato)metal Compounds of the Nickel Triad: Solid State Design by Molecular Engineering

Zeitschrift für Naturforschung B ◽

10.1515/znb-1977-0508 ◽

1977 ◽

Vol 32 (5) ◽

pp. 516-527 ◽

Cited By ~ 33

Author(s):

H. Endres ◽

H. J. Keller ◽

R. Lehmann ◽

A. Poveda ◽

H. H. Rupp ◽

...

Keyword(s):

Solid State ◽

Linear Chain ◽

Mixed Valence ◽

Structural Data ◽

Molecular Engineering ◽

Complex Molecules ◽

Metal Compounds ◽

Metal Interactions ◽

Wide Range ◽

Metal Metal

Chemical and structural data of numerous bis(α,β-dionedioximato)metal(II) compounds are summarized. All of them crystallize in columns but principally two different kinds of molecular arrangements occur in the solids. In one phase the molecular planes are inclined to the direction of the linear metal chains with an angle different from 90°. This allows only indirect interactions between the metal ions via the ligand. (“M—L—M” stacking.) The other modification consists of molecules with their planes perpendicular to the M—M-chains. This form allows direct metal-metal contacts (“M—M” modification). Depending on a few molecular parameters a “M—L—M” or a “M—M” stacking is obtained upon crystallization. Since for those compounds which could be isolated in both modifications the M—L—M form has the higher density it is concluded that only stronger M—M interactions stabilize the less dense M—M forms.A wide range of metal-metal separations with a lower limit of 3.15 Å in mixed valence systems are found in different “M—M” compounds. In any case the intrachain metal-metal distances are reduced considerably upon oxidation of the bivalent complex molecules. The influence of “electronic” and “sterical” parameters of the complex molecules on the intermolecular metal interactions and on the type of columns in the solid state is discussed.

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Electronic structure and stability of the inorganic fulminates

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1967.0225 ◽

1967 ◽

Vol 302 (1468) ◽

pp. 35-49 ◽

Cited By ~ 16

Keyword(s):

Solid State ◽

Silver Salt ◽

Structural Data ◽

Sodium Potassium ◽

Small Crystals ◽

Ionic Solids ◽

Mercury Salts ◽

The Stability ◽

High Degree ◽

Deposited Films

The fulminates form a class of compounds isoelectronic with the azides and cyanamides. They are, however, extremely sensitive materials and even the ionic salts explode. A study has been made of some of the optical properties of small crystals and thin deposited films, and of the solid state infrared spectra, in order to determine the nature of the bonds in the sodium, potassium, thallous, silver and mercury salts. Structural data is also available and it is concluded that while sodium, potassium and thallous fulminates are ionic solids, the mercury salt is covalent. It is likely that in the silver salt there is also a high degree of directed bonding in the solid state. The nature of the bond between the metal and the carbon atom of the fulminate group can, however, be different in the silver and mercury salts and this will be reflected in the order of the stability of the salts.

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