Activity profiles halogenation

Kramers, P.G., Mout, H.C., Bissumbhar, B. Mulder, C.R. (1991) Inhalation exposure in Drosophila mutagenesis assays experiments with aliphatic halogenated hydrocarbons, with emphasis on the genetic activity profile of 1,2-dichloroethane. Mutat. Res., 252, 17-33... 

The high activity of Nd-based catalysts was reported by Shen et al. in 1980 [92], In this publication, the polymerization activity of the whole lanthanide series was studied. Ln halogen-based binary catalyst systems (LnCb/EtOH/AlEts or LnCl3 (TBPU/Al Bua), as well as Ln-carboxylate-based ternary catalyst systems (Ln(naphthenate)3/AlIBu3/EASC) were used. The activity profile for the entire series of lanthanides is depicted in Fig. 2. Two years later, Monakov et al. confirmed in a similar study that Nd is the most active Ln element [93,94]. 

The increased lipophilicity (n), and a superior metabolic stability compared with the methyl analogue, often leads to an improved activity profile. Mono-fluorination and trifluorination of saturated aliphatic groups normally decrease lipophilicity, whereas higher fluoroalkyl groups (perfluoroalkyl groups) are introduced mainly to increase the lipophilicity [61], as recently shown for the 4 -perfluoro-iso-propyl-2-methyl-phenyl-amide fragment (4 -position halogen < fluoroalkoxy < CFj < C2 4-fluoroalkyl) in flubendiamide 54 ISO-proposed Nihon Nohyaku Co., Ltd./Bayer CropScience) (for more details see Chapter 31). 

For hydrophilic proteins and peptides the double emulsion/solvent evaporation method is considered as the most convenient because of its encapsulation efficiency and biologically active stability [43]. However, the double emulsion/solvent evaporation method posesses several liabilities such as the required use of toxic solvents that are not easy to fully eliminate (hydrophobic and halogenated solvent) and the inadequate protein release profile. [44-46]. Fxuthermore, the production of acid degradation products, particularly lactic acid, is the primary instability source for the encapsulated acid-labile protein or peptide [6,8],... 

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