Conformational strain

The reduced oxidation near sample corners is related to these stress effects, either by retarded diffusion or modified interfacial reactionsManning described these stresses in terms of the conformational strain and distinguished between anion and cation diffusion, and concave and convex surfaces. He defined a radial vector M, describing the direction and extent of displacement of the oxide layer in order to remain in contact with the retreating metal surface, where ... 

A different approach toward cyclic peptides has been presented by Leatherbarrow and coworkers, employing ring-dosing metathesis (RCM) on a solid support [50], The authors reported on the synthesis of conformationally strained cyclic peptides of the Bowman-Birk inhibitor type, which are naturally occurring serine protease... 

Molecular mechanics calculations on two 6-arylpyrrolo[2,l-d][l,5]benzothia-zepines (1995JMC4730) confirmed that binding to a mitochondrial benzodiazepine receptor depends on conformational strain as well as on specific repulsive interactions involving their side-chains. 

The strain in ring structures is of two types—angle strain and conformational strain. Ring structures of less than five atoms are highly strained due to the high degree of angle strain,... 

A very easy cyclodehydration of the pyrimidine (39) using silicon tetrachloride and base yields the tricyclic adenine derivative (40), a conformationally strained analogue of the anticonvulsant compound BWA78U [95TL4249],... 

Diphenylsilane is compatible with the ester group at C-4 in azetidin-2-ones 203 and reduces only the amide carbonyl group affording azetidin-2-carboxylates 204 (Equation 55) <2004TL2193>. Removal of the />-methoxy-benzyl group from azetidin-2-carboxylates 204 allowed the preparation of conformationally strained amino ester hydrochlorides. 

Release of high-energy water Release of conformational strain Van der Waals forces Hydrogen bonding London dispersion forces Dipole-dipole interaction... 

An additional constant term C accounts for the change of entropy of the system due to the decrease of free molecules concentration (critic factor) and the loss of rotational/translational degrees of freedom. Conformational strain and dynamics of the process are incorporated in the C parameter and can be adjusted from one set of complexes to another.77 The free energy is defined as ... 

Srivastava D, Brenner DW, Schall JD, Ausman KD, Yu M-F, Ruoff RS (1999) Predictions of enhanced chemical reactivity at regions of local conformational strain on carbon nanotubes kinky chemistry. J. Phys. Chem. B 103 4330-4337... 

In toluene (LXX), like in a number of analogs, the preferred conformation shows eclipsing between a hydrogen atom and the w-system, as represented in diagram LXX. This conformation minimizes a- and w-electron loss to the 7r-system (hyperconjugation) and therefore allows maximal one-electron interaction [80]. Toluene is characterized by an extremely low rotation barrier (a few cal/mol) due to the fact that this barrier is sixfold, and the latter is always found to be extremely small. Indeed, an equivalent conformation is found after every 60° rotation, and no real relief of conformational strain is obtained after a rotation of only 30°. 

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