Polyprenylated polycyclic acylphloroglucines (PPAPs) are a family of natural products that possess a wide range of different important biological activities because of the relative position and configuration of four substituents that decorate one common central bicyclo[3.3.1]nonane-2,4,9-trione core. The rigid bicyclic framework with its lipophilic side chains and its hydrophilic trione moiety represents a nature-derived lead structure that arranges the substituents (R(1) to R(4)) into a defined topographical orientation. As the substituents are responsible for the biological activities, the seven-step synthetic approach presented here sets the stage for an iterative introduction of R(1) to R(4) and thus generates structurally diverse trans-type B PPAPs. Four natural and one non-natural trans-type B PPAPs were prepared starting from acetylacetone with overall yields that ranged from 6 to 22%. The concept of separating framework construction from decorating transformations plus the minimization of protecting-group operations are the key issues for the realization of our synthetic approach.

Iron at the crossroads: A remarkable mechanistic dichotomy in iron‐catalyzed allylic substition increases not only the scope of regioselective allylic alkylation but could also herald the development of asymmetric allylic substitution (see Scheme, MTBE=methyl tert‐butyl ether). Depending on the ligand used, either a σ‐ or a π‐allyl mechanism is observed.

In order to improve the water solubility of nonpolar compounds such as drugs or dyes, new amphiphilic molecules are needed. In this paper we describe a new class of triblock amphiphiles that we have synthesized by a straightforward convergent approach. These amphiphiles each consist of a nonpolar biphenyl core and a polar shell based on various generations of monoamino polyglycerol dendrons, coupled to the core through amide linkages (1). For the synthesis of these monoamino dendrons we applied a simple iterative two‐step process based on allylation of an alcohol group and catalytic dihydroxylation. As starting materials, D,L‐serine/serinol and – in a second, similar pathway – commercially available triglycerol were used. The transport behavior of these defined triblock amphiphiles was then investigated with the nonpolar dye Nile Red in water.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

Eisen am Scheideweg: Ein ungewöhnlicher Wechsel des Mechanismus der Fe‐katalysierten allylischen Substitution je nach eingesetztem Liganden vergrößert nicht nur die Anwendungsbreite der regioselektiven Allylierung, sondern könnte auch der Ausgangspunkt zur Entwicklung einer asymmetrischen allylischen Substitution sein (siehe Schema; MTBE=Methyl‐tert‐butylether).

The title compound, C26H38O3, was prepared by an intra­molecular Claisen-like cyclization of ethyl 2-acet­oxy-4,4-dimethyl-1-(3-methyl­but-2-en­yl)cyclo­hex-2-enecarboxyl­ate followed by dialkyl­ation. One of the methyl groups is disordered over two sets of sites in a 0.67:0.33 ratio.