Solution mixing synthesis

Kits. Kits for the preparation of radiopharmaceuticals are a convenient solution to synthesis of products containing short-Hved radionucHdes (eg, In, I, Tc) bound to a nonradio active moiety. The labeling step is performed either at a commercial radiopharmacy, or within the institutional nuclear medicine laboratory. The kits are usually stored as a frozen solution or lyophilized product. The material of interest is then metered out into kit dosages. The kit vials are thawed or reconstituted and mixed with the appropriate radionucHde. 

There are three methods of making polymer blends mechanical blending, solution mixing, and chemical synthesis. This chapter will focus only on the mechanical blending of polymers. 

An important breakthrough in that respect was the use of soHd-phase organic synthesis (SPOS) where the attachment of the substrate to an insoluble support allowed for easy workup (filtration) and for rapid generation of products via split-mix procedures [1,2]. An important subsequent development consisted of the immobihzation of reagents, scavengers and catalysts. This technique, coined polymer-assisted solution phase chemistry (PASP), allowed solution phase synthesis of compoimds, yet still enjoying the bene-... 

Another path affording novel pigments is the mixed synthesis yielding solid solutions. The mixed synthesis of two DPP pigments can result in solid solutions, which consist of the two symmetrically and the unsymmetrically substituted DPP pigment. Solid solutions can also be obtained from DPP pigments and quin-acridone pigments. 

In the early solution-phase synthesis of oligonucleotides, coupling of phosphate chesters was used. A mixed 3 -ester with one aryl substituent, usually o-chlorophenyl, was coupled with a deprotected 5 -OH. The coupling reagents used were sulfonyl halides, particularly 2,4,6-triisopropylbenzenesulfonyl chloride.153 The reactions proceed by... 

Formation of a symmetrical sulphide (a) (e.g. dipropyl sulphide, Expt 5.204), is conveniently effected by boiling an alkyl halide (the source of carbocations) with sodium sulphide in ethanolic solution. Mixed sulphides (b) are prepared by alkylation of a thiolate salt (a mercaptide) with an alkyl halide (cf. Williamson s ether synthesis, Section 5.6.2, p. 583). In the case of an alkyl aryl sulphide (R-S Ar) where the aromatic ring contains activating nitro groups (see Section 6.5.3, p. 900), the aryl halide is used with the alkyl thiolate salt. The alternative alkylation of a substituted thiophenol is described in Section 8.3.4, p. 1160. The former procedure is illustrated by the preparation of isobutyl 2,4-dinitrophenyl sulphide (Expt 5.205) from l-chloro-2,4-dinitrobenzene and 2-methylpropane-1-thiol. 

Figure 2.2. Schematic of synthesis of CNT polycarbonate nanocomposites by solution mixing approach. Reproduced from reference 19 with permission from American Chemical Society.

Subramanian, T., Wang, Z., Troutman, J.M., Andres, D.A., and Spiehnann, H.P. (2005). Directed library of anilinogeranyl analogues of farnesyl diphosphate via mixed solid- and solution-phase synthesis. Org Lett 7 2109-2112. 

In this method, peptides or small molecules are prepared by the split-mix synthesis method and cleaved from the resin to form an encoded solution-phase library such that each library compound is tethered to a PNA code via a hydrophilic linker (11). The library then is mixed with the target protein and later exposed to planar oligonucleotide microarrays of predetermined sequences. Alternatively, the encoded soluble library can be hybridized to the oligonucleotide microarrays before incubation with the target protein. 

SPPS - Solid phase parallel synthesis SPMS - Solid phase split-mix synthesis Ind - Indexed ID - Iterative deconvolution Tag - Tag encoded SolPS - Solution phase parallel synthesis SolMS - Solution phase mixture synthesis... 

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