Side chain length

Compression-molded devices of poly(N-palmitoyl hydroxyproline ester) (side chain length 16 carbons), poly(N-decanoylhydroxy-proline ester) (side chain length 10 carbons), and poly(JN-hexanoyl-hydrox roline ester) (side chain length 6 carbons) were prepared with dye contents of 1,5,10, and 20% of either -nitroaniline or acid orange. Release curves were obtained by placing the loaded devices into phospate buffer (pH 7.4) at 37 C. The amount of released dye was followed spectrophotometrically in the usual fashion. 

Lastly, it was demonstrated with PPO substituted with a series of alkyl side-chains as we have here, that the glass transition temperature decreases with an increase in the side-chain length (28). At the same time, the Tg s of the more flexible side-chain liquid crystalline polymers investigated to date are always much higher than those of the corresponding polymers without the mesogenic side-chains (3). Therefore, it is quite likely that we may obtain side-chain liquid crystalline polymers of approximately the same Tg from PPO and PECH. 

The side chain substituents can affect the properties of the polyphosphazenes in yet another way. Whereas (NP CH.CH ), is amorphous, increasing the side chain length by using long chain alcohols can result in polymers which are semicrystalline (13). Presumably these polymers assume more of the character of poly(ethylene oxide), as the side chain length increases. 

A homologous dibenzopyrene compound 51, which differs from 48 only in side-chain length, was studied by the same authors and shown to have two ferroelectric phases.58,59 The coexistence of the two columnar phases depended... 

The overall objective of these studies is to unravel mechanisms of interfacial PT. This requires identification of collective coordinates (or reaction coordinates) and transition pathways of transferring protons. Differences in activation energies and rates of corresponding mechanism due to distinct polymer constituents, acid head groups, side chain lengths, side chain densities, and levels of hydration have to be examined. Comparison with experimental... 

Figure 11 Unnatural amino acids to probe the inactivation mechanism of ion channel Kv1.4. OMeTyr or dansylalanine extends the side chain length of tyrosine, which impedes the inactivation peptide from threading through the side portal of the ion channel and abolishes the fast inactivation, as shown in the current-time curve in the bottom panel.

Fig. 32 a-d. Phase transition a from the extended coil b to a globule state as found by scaling analysis [83] c the transition is caused by lowering the surface pressure below a certain critical value TTc at which the fraction of adsorbed monomers 3=N2d/N undergo discrete changes d hereby, the depends critically on the side chain length... 

Rodriguez-Saona CR, Maynard DF, Phillips S, Trumble JT, AlkyRurans Effects of alkyl side-chain length on insecticidal activity, J Nat Prod 62 191—193,... 

The monomers in Scheme 7 show increased hydrophilicity with increased side chain length, and thereby the cloud points are expected to be higher. A wide range of LCST values could be achieved by combining OEGMA monomers having short and... 

This chapter aims to summarize our efforts to investigate the effects of fluorinated amino acid substitutes on the interactions with natural protein environments. In addition to a rather specific example concerning the interactions of small peptides with a proteolytic enzyme, we present a simple polypeptide model that aids for a systematic investigation of the interaction pattern of amino acids that differ in side chain length as well as fluorine content within both a hydrophobic and hydrophilic protein environment. Amino acid side chain fluoiination highly affects polypeptide folding due to steric effects, polarization, and fluorous interactions. 

Table IV. Relation between Tastes of O-Aminoacyl Sugars and Side Chain Length of Amino Acid Moiety...

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