Molecular tailoring approach

M. M. Deshmukh, L. J. Bartolotti, and S. R. Gadre, Intramolecular hydrogen bonding and cooperative interactions in carbohydrates via the molecular tailoring approach, J. Phys. Chem. A, 112 (2008) 312-321. 

Much research work has been done and continues to be done on the development of new dyes for this outlet. For instance, Avecia have a range of yellow magenta and cyan dyes, based on the ammonium salt principle above, which do show improved wet fastness properties. An alternative approach adopted by workers at Ilford, based on their experience in colour photography, involves the molecular tailoring and formulation of dyes which aggregate and hence have light fasmess properties nearer to pigments (Archiva Inks). 

The goal of many biomolecular NMR studies is characterization of global molecular structure. In metallo-biomolecules, and in particular, for paramagnetic species, it is sometimes preferable to use NMR to perform a more focused study of the metal ion coordination enviroiunent and the metal electronic structure. Metal sites show great variation in the effects on chemical shifts and line widths and thus often call for tailored approaches. In this section, characteristics of some of the metalloproteins metal sites most frequently studied by NMR are summarized. Examples have been selected to illustrate approaches described in this chapter such as metal substitution, use of pseudocontact shifts, RDCs, relaxation enhancement, and detection of nuclei other than H. 

Weissbuch, I, Lahav, M., and Leiserowitz, L. (1999). Towards an Understanding and Control of Nueleatlon, Growth, Habit and Structure of Crystals Using Tailor-Made Auxiliaries." In Molecular Modeling Approaches in Crystallization (Myerson, A.S., ed.), Chapter 4, Cambridge University Press, Cambridge, UK. 

We have developed and applied the ALTA (anchor-based library tailoring) approach to identify ATP-competitive inhibitors of EphB4 [99] (Eigure 17.5). ALTA is an automatic fragment-based procedure for focusing libraries of compounds. First, molecular fragments are docked and prioritized (i.e., anchors are selected based on a... 

Pradip, and Rai, B. 2002a. Design of tailor-made surfactants for industrial apphcations using a molecular modelling approach. Colloids Surf. A. 205 139. 

A challenging task in material science as well as in pharmaceutical research is to custom tailor a compound s properties. George S. Hammond stated that the most fundamental and lasting objective of synthesis is not production of new compounds, but production of properties (Norris Award Lecture, 1968). The molecular structure of an organic or inorganic compound determines its properties. Nevertheless, methods for the direct prediction of a compound s properties based on its molecular structure are usually not available (Figure 8-1). Therefore, the establishment of Quantitative Structure-Property Relationships (QSPRs) and Quantitative Structure-Activity Relationships (QSARs) uses an indirect approach in order to tackle this problem. In the first step, numerical descriptors encoding information about the molecular structure are calculated for a set of compounds. Secondly, statistical and artificial neural network models are used to predict the property or activity of interest based on these descriptors or a suitable subset. 

A somewhat different approach to providing tailored cavities for metal cations was taken by the groups of Cram and Lehn °. Graf and Lehn prepared the spheroidal molecule 21 which has an interesting molecular architecture. The molecule has ten coordination sites within it, six which form an octahedral array and four which are in a tetrahedral arrangement. This remarkable compound is soluble in all solvents from petroleum... 

B. Sellergren, Enantiomer separation using tailor-made phases prepared by molecular imprinting in A practical approach to chiral separations by liquid chromatography, G. Subramanian, VCH, Weinheim (1994) Chapter 4. 

Since multiple electrical and optical functionality must be combined in the fabrication of an OLED, many workers have turned to the techniques of molecular self-assembly in order to optimize the microstructure of the materials used. In turn, such approaches necessitate the incorporation of additional chemical functionality into the molecules. For example, the successive dipping of a substrate into solutions of polyanion and polycation leads to the deposition of poly-ionic bilayers [59, 60]. Since the precursor form of PPV is cationic, this is a very appealing way to tailor its properties. Anionic polymers that have been studied include sulfonatcd polystyrene [59] and sulfonatcd polyanilinc 159, 60]. Thermal conversion of the precursor PPV then results in an electroluminescent blended polymer film. 

Tailoring block copolymers with three or more distinct type of blocks creates more exciting possibilities of exquisite self-assembly. The possible combination of block sequence, composition, and block molecular weight provides an enormous space for the creation of new morphologies. In multiblock copolymer with selective solvents, the dramatic expansion of parameter space poses both experimental and theoretical challenges. However, there has been very limited systematic research on the phase behavior of triblock copolymers and triblock copolymer-containing selective solvents. In the future an important aspect in the fabrication of nanomaterials by bottom-up approach would be to understand, control, and manipulate the self-assembly of phase-segregated system and to know how the selective solvent present affects the phase behavior and structure offered by amphiphilic block copolymers. 

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