Synthetic Oligoamides as Protein Models

Pettigrew, Robert (1968) Synthetic Oligoamides as Protein Models. PhD thesis, University of Glasgow.

Abstract

The aspect of protein structure, for which a simple model was sought in the present investigations, was that of their tertiary structure. It is pointed out that there are certain similarities between this organisation, and that to be found in the folding of the polymer chain that has been recorded as being present in polymeric material recrystallised from dilute solution. A prerequisite for studying the conformational properties of polymers, and more specifically the effects introduced by the inclusion of a variety of groups at the turning points of their fold-chain crystals, is the efficient synthesis of very long monomer units. These monomer units should, for our purposes, be approximately 70 to 80A in length. The present studies were undertaken in order to devise an efficient and flexible method of synthesising such long molecules. A stepwise reaction technique has been evolved which is sufficiently flexible for groups of differing size and polarity to be introduced at the ends of the linear oligoamide chains, and the technique refined to the stage where the small scale preparation of high molecular weight oligoamides has become practicable. Using this technique, several new series of linear oligoamides have been synthesised. These series were designed so that investigations might, much later, be carried out into the effects that different terminal groups on the monomers might have on their crystal structure, and also on the solution properties of the polymeric materials derived from them. Section two of this thesis is concerned with an alternative method of synthesis of specific high molecular weight linear oligoamides, namely through a "Doubling Reaction", It is pointed out that this method has up to now been neglected, largely owing to the low yields obtained when trying to activate, or to protect, just one of two symmetrically placed identical functional groups. After some preliminary work was carried out covering a wide range of separation techniques, an improvement was instituted whereby this difficulty might be overcome. The doubling reaction technique is thought to be capable of being made more efficient by the use of highly coloured or fluorescent materials, introduced either by the preparation of suitable derivatives at the ends of the constituent parts, or actually within the molecules themselves. This inclusion enables the materials to be synthesised by normal methods and yet to be readily followed in very low concentrations during chromatographic or other separation techniques. A brief mass spectral investigation of certain of the compounds synthesised in these investigations was undertaken with a view to showing something of the possibilities of such a technique in obtaining a sequential analysis of peptides. From the very brief inspection of the mass spectra obtained (which is all that time would allow) it would seem that, although complex, they are capable of interpretation and also of yielding a sequential analysis.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Organic chemistry
• Date of Award: 1968
• Depositing User: Enlighten Team
• Unique ID: glathesis:1968-78469
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 28 Feb 2020 12:09
• Last Modified: 28 Feb 2020 12:09
• URI: https://theses.gla.ac.uk/id/eprint/78469