Pseudo poly

Infrared spectroscopy has been widely used for the qualitative and quantitative characterization of polymorphic and pseudopolymorphic compounds of pharmaceutical interest. Since solid state IR can be used to probe the nature of (pseudo)polymorphism on the molecular level, this method is particularly useful in instances where full crystallographic characterization of (pseudo)poly-morphism was not found to be possible. Recently, a significant number of publications have appeared that discuss where a multidisciplinary, spectroscopic... 

An alternative approach for the preparation of CD-based polyrotaxane using photoreactions is described (Scheme 9). The authors prepared a-CD-based polyrotaxanes by capping ends of a-CD-PPG complexes, in a pseudo-poly-rotaxane structure, with covalently bound stoppers. A polyrotaxane containing a number of /3-CD molecules was prepared by photoreactions of a precursor complex between /3-CD with PPG having a triphenyhnethyl group at... 

Pseudo)polyrotaxanes containing CB[6J threaded on organic polymers were also reported. Such (pseudo)poly-rotaxanes were synthesized by interfacial polymerization of CB[6]/polyamine pseudorotaxane with diacid chlorides such as 1,6-hexanedioyl chloride (adipoyl chloride). "" Steinke and coworkers recently reported a novel way to produce polyrotaxanes utilizing 1,3-dipolar cycloaddition between azide and alkyne inside the cavity of They also synthesized pseudopolyrotaxanes... 

Introduction 207 12.5 Carbonate-Based "Pseudo" Poly(Amino Acids) 212... 

Synthesis of "Pseudo" Poly(Amino Acid) 208 12.5.1 Synthesis of Carbonate-Based "Pseudo" ... 

FIGURE 12.1 General scheme of pseudo poly(amino acids) where H-N-A is the amino acid, and are linking groups, and P is the protecting group. 

ESTER-BASED "PSEUDO" POLY(AMINO ACIDS)... 

Esters are the most common functional groups used to synthesize pseudo poly(amino acids) because of their well-characterized reaction schemes for condensation reactions and the availability of the multiple reactants and catalysts. Table 12.1 summarizes ester-based pseudo poly (amino acids). The presence of hydroxyl (on serine, threonine. 

FIGURE 12.2 Common amino acids used for synthesis of pseudo poly(amino acids). 

FIGURE 12.3 General reaction scheme for pseudo poly(amino acids) where P is a protecting group is either diisocyanate, polyol, or diamine is either dicarboxylic acid or diisocyanate and L -L is a prepolymer. 

TABLE 12.1 "Pseudo" Poly(amino acids) Formulated with Esters ... 

An exception to the definition for pseudo poly(amino acids) as previously established is a polymer synthesized by Chen et al. [31,32], because its backbone is comprised of lysine alternating with an isophthaloyl group and lacks nonamide linkages (Table 12.2). Hydrophobicity of the polymer is increased by conjugating ethanol or hydro-phobic amino acids, such as valine, leucine, and phenylalanine, as protecting groups on the carboxyl terminal of lysine via carbodiimide chemistry. This protected lysine is then copolymerized with isophthaloyl chloride via single-phase polymerization in the presence of a base (Table 12.2) [32]. 

Applications Poly(Amides) as "Pseudo" Poly(Amino Acids)... 

Carbonates (ester of carbonic acid) are functional groups in which the carbon atom is surrounded by three oxygen atoms. This structure consists of two single and one double bonds. Carbonate-based pseudo poly(amino acids) are the first bioactive polymers to be synthesized and have been reported initially by Kohn [40,41]. The molecular weights of these polymers range from 120 to 450 kDa [40,41]. Their... 

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