Template-Mediated Biomineralization for Bone Tissue Engineering.

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.

Synthesis and first complexes of C(4/5) P-bifunctional imidazole-2-thiones.

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').