New developments in solid phase synthesis supports

Aminopolycarboxylic acid functionalized adsorbents for heavy metals removal from water

Due to the excellent chelating properties of aminopolycarboxylic acid (APCAs), they can be used for the removal of metals from contaminated waters. This paper reviews the research results obtained for both commercial and self-prepared adsorbents functionalized with four most common APCAs: iminodiacetic acid (IDA), nitrilotriacetic acid (NTA), ethylenediaminetetraacetic acid (EDTA), and diethylenetriaminepentaacetic acid (DTPA). The structural characteristics and unique metal binding properties of these chelating adsorbents are presented. The theory of the adsorption phenomena is discussed based on the kinetics of adsorption, equilibrium adsorption isotherm models, and thermodynamic models. The most important applications of APCA-functionalized adsorbents are also described. APCA-functionalized adsorbents are found to be highly promising materials for metal removal from contaminated waters.

Enzymatically cleavable linker groups in polymer-supported synthesis

Access to broadly applicable linker groups that are stable under a variety of reaction conditions and enable the release of target compounds from polymeric supports under the mildest conditions is a major goal in combinatorial chemistry. Here, we summarize the development of enzymatically cleavable linker groups used to prepare a variety of different target molecules on polymeric supports.

Regio-reactive resin: a platform for orthogonal loading using the polymer backbone and cross-linker

A new support for solid-phase combinatorial organic synthesis has been developed, which we term a regio-reactive resin (R(3)-resin). The resin is based on a unique hydroxyl-functionalized cross-linker readily synthesized in two steps starting from 4-hydroxybenzaldehyde. The cross-linker's ease of synthesis and high purity enables the preparation of gel-type resins with regio-reactive orthogonal loading sites. The resin's swelling properties were investigated, and its potential utility was demonstrated via orthogonal reactivity of the pendant and cross-linker sites.

The use of power ultrasound coupled with magnetic separation for the solid phase synthesis of compound libraries

Enhanced reaction rates are observed when power ultrasound is utilized as a substitute for mixing during solid phase organic chemical reactions on a paramagnetic support. Power ultrasound is also used to facilitate the washing of the paramagnetic support as it is magnetically separated from the reaction mixture. Selective examples from a library targeting the kappa-opioid receptor are presented.