A synthetic route to C(4/5)-bis(phosphinoyl)imidazole-2-thiones (7d,e) (d: R(1) = (n)Bu, R(2) = Me; e: R(1) = n-dodecyl, R(2) = Me) and C(4/5)-bis(thio/selenophosphinoyl)imidazole-2-thiones (8b,c), (9a,b,e) and 10a (a: R(1) = R(2) = Me; b: R(1) = R(2) = Ph, c: R(1) = (i)Pr, R(2) = Me) is presented that employs initial C(5) lithiation of mono-phosphinoyl/thiophosphinoyl substituted imidazole-2-thiones (3c-e)/(4a-c,e) followed by reaction with chlorodiphenylphosphane, leading to mixed phosphinoyl and phosphanyl substituted imidazole-2-thiones (5c-e) or mixed thiophosphinoyl and phosphanyl substituted imidazole-2-thiones (6a-c,e). Subsequent oxidation of mixed phosphinoyl and phosphanyl substituted imidazole-2-thione (5d,e) with H2O2-urea gives the bis(phosphinoyl) substituted imidazole-2-thiones (7d,e), and the oxidation of mixed thiophosphinoyl and phosphanyl substituted imidazole-2-thione (6a-c,e) using H2O2-urea, elemental sulfur or elemental selenium gives a set of mixed P(V)-chalcogenide substituted imidazole-2-thiones (8b,c), (9a,b,e) and 10a, respectively. P(V,V) substituted imidazole-2-thiones 7d and 9a reacted with tellurium tetrachloride, titanium tetrachloride or palladium dichloride to give complexes 11d, (12d and 12d') and 14a, respectively, having a bidentate chelate (11d and 14a) or a monodentate bonding motif (12d,d'). The titanium complexes 12d,d' slowly and selectively converted into the mono-ethoxy substituted product 13 possessing a seven membered chelate motif being unprecedented in the titanium chemistry of phosphine oxide donor ligands. The compounds were characterized by elemental analyses, spectroscopic and spectrometric methods and, in addition, X-ray diffraction studies in the case of 5c, 7d, 8b, 9a and 13.

Template-mediated mineralization describes a research field of materials chemistry that deals with templates influencing product formation of foremost inorganic functional materials and composites. These templates are usually organic compounds - as far as molecules with natural origin are involved, the terminology "biomineralization" or "biomimetic mineralization: is used. The present review gives insight into recent developments in the research area of bone-tissue engineering with focus on chemical templates and cell-based approaches. The review is structured as follows: (1) a brief general overview about the principle of templating and recently used template materials, (2) important analytical methods, (3) examples of template-guided mineralization of various bone-related materials, (4) natural bone mineralization, (5) scaffolds for bone-tissue regeneration and (6) cell-based therapeutic approaches. For this purpose, a literature screening with emphasis on promising potential practical applications was performed. In particular, macromolecular structures and polymer composites with relation to naturally occurring compounds were favored. Priority was given to publications of the last five years. Although the present review does not cover the whole topic to full extent, it should provide information about current trends and the most promising approaches in the research area of bone-tissue engineering based on applications of organic templates/scaffolds as well as cell-based strategies.