Hydrocarbon side-chain

Whilst c /5-1,4-polybutadiene is a rubber, 1,2-polybutadiene is thermoplastic. Such a material is very similar in structure to polybut-l-ene except that the hydrocarbon side chain is unsaturated ... 

How many of the a-amino acids shown in Table 26.1 contain aromatic rings How i many contain sulfur How many contain alcohols How many contain hydrocarbon. side chains ... 

Later, surface-acting polyglucosides were created. These sugar-based detergents are easily broken down by microbes, leaving no traces in the environment. They consist of a pair of glucose molecules, with hydrocarbon side chains attached to act as the hydrophobic ends. They are milder than soaps, and they work in hard water. 

Another type of gel expands and contracts as its structure changes in response to electrical signals and is being investigated for use in artificial limbs that would respond and feel like real ones. One material being studied for use in artificial muscle contains a mixture of polymers, silicone oil (a polymer with a (O—Si—O—Si—) — backbone and hydrocarbon side chains), and salts. When exposed to an electric field, the molecules of the soft gel rearrange themselves so that the material contracts and stiffens. If struck, the stiffened material can break but, on softening, the gel is reformed. The transition between gel and solid state is therefore reversible. 

The names of straight-chain alkanes are given in Table 18.1 they all end in -ane. Name a hydrocarbon side chain as a substituent by changing the ending -ane to -yl (as in the last two columns in Table 18.1). 

The functional group has priority in numbering over hydrocarbon side chains. 

Table 6.9 A -THC CONSTRAINED, UNSATURATED AND AROMATIC HYDROCARBON SIDE CHAINS...

The first attempt to develop a PET radioligand for imaging brain CB1 receptors involved modification of A8-THC by labeling with fluorine-18 in the hydrocarbon side chain [16,17], as shown in Figure 2. Unfortunately,... 

Peters, D., and J. Peters. 1982. Quantum Theory of the Structure and Bonding in Proteins Part 13. The p branched hydrocarbon side chains valine and isoleucine. J. Mol. Struct. (Theochem) 88,157-170. 

Snyder and Rapoport photolysed phylloquinone (vitamin K-l, 82) in cyclohexane solution with the surface exposed to atmospheric oxygen and moisture. This system was adopted on the assumption that the in vivo photo-oxidation would occur with the hydrocarbon side-chain dissolved in a lipid layer, but the polar naphthoquinone moiety would be in contact with water. Under the... 

Isoleucine (He or I) ((25,35)-2-amino-3-methylpentanoic acid) is a nonpolar, neutral, aliphatic amino acid with the formula HOOCCH(NH2)CH(CH3)CH2CH3. Having a hydrocarbon side chain. He is classified as a hydrophobic amino acid. Together with Thr, He is one of the two common amino acids that have a chiral center. Although four stereoisomers of He are possible. He present in nature exists in only one enantiomeric form, that is, (25,35)-2-amino-3-methylpentanoic acid. ... 

In the formulas, the symbols R and R usually denotes an attached hydrogen, or a hydrocarbon side chain of any length, but may sometimes refer to any group of atoms. 

In general, the standard enthalpy of micellization is large and negative, and an increase in temperature results in an increase in the c.m.c. the positive entropy of micellization relates to the increased mobility of hydrocarbon side chains deep within the micelle as well as the hydrophobic effect. Hoffmann and Ulbricht have provided a detailed account of the thermodynamics of micellization, and the interested reader will find that their tabulated thermodynamic values and treatment of models for micellar aggregation processes are especially worthwhile. 

Highly fluorinated amino acids, such as hexafluoroleucine and hexafluorovaline, enhance the stability of several helical proteins. This enhancement has been attributed to the higher hydrophobicity of the fluorocarbon side chain compared to that of the natural hydrocarbon side chain. 

Quinones are among the best-behaved organic compounds to undergo redox reactions in aqueous solutions. There are a reasonably large number of synthetic and natural products containing the quinone moiety, and many are excellent candidates for selective determination by LCEC. Unfortunately, some of the most important of these compounds are extremely hydrophobic due to the presence of long hydrocarbon side chains, and are therefore quite difficult to study by reversed-phase LC. 

C. Derivatives with a Hydrocarbon Side Chain 1. Alkylbenzo[b]thiophenes... 

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