T. Schäfer3, B. Sorg, C. Karalaib, E. Hecker* Deutsches Krebsforschungszentrum, Division Mechanisms of Tumorigenesis, Research Program 3, Risk Factors of Cancer and Cancer Prevention, Im Neuenheimer Feld 280, D-69009 Heidelberg, Germany Z. Naturforsch. 49b, 128-134 (1994); received September 6,1993 Daphnane Derivatives, Diterpene Esters, Simplexin, Skin Irritant Activity, Skin Tumor Promoting A...

ZrOCl2.8H2O@nano SiO2 has been synthesized for the first time via a simple procedure and characterized by SEM (scanning electron microscopy), FT-IR, and EDX (energy-dispersive X-ray) techniques. The efficiency of the prepared nanostructure has been explored for the synthesis of benzimidazoles via the condensation reaction of orthoesters and diamines at 60 °C under solvent-free conditions. The s...

Nature has inspired researchers to construct structures with ordered layers as candidates for new materials with high mechanical performance. As a prominent example, nacre, also known as mother of pearl, consists of a combination of inorganic plates (aragonite calcium carbonate, 95% by volume) and organic macromolecules (elastic biopolymer, 5% by volume) and shows a unique combination of streng...

Taking into account the thiophilic properties of iodine, a very simple methodology to achieve 2 0,3 0-didehydro-2 0,3 0-dideoxy-b-nucleosides in high yield was performed, using mild, and inexpensive conditions, by means of the treatment of 2 0-deoxy-3 0,5 0dibenzoyl-2 0-iodo-b-nucleoside derivatives with NaHS. The process has shown to be highly dependent of the relative geometry between the iod...

The neoclerodane diterpene salvinorin A (1) was isolated in 1982 from the rare mint SalVia diVinorum, indigenous to Oaxaca, Mexico.1 Recent efforts established salvinorin A as a potent and selective κ opioid receptor agonist, the only non-alkaloid psychoactive substance, and the most potent naturally occurring hallucinogen.2 As a result of its therapeutic potential, renewed isolation efforts ha...