Lignin building stones

These and many other facts must be considered when constructing a constitutional scheme for lignin, but they are by no means sufficient for building up such a formula. Special constitutional information is given by the structures of the lignin-building stones described in the following sections. These form the major content of this paper and are described in detail. 

Table II also lists the C.O.P. value of coniferyl alcohol, the basic lignin building stone of coniferous lignins. The low value indicates the rather...

Lignin may be defined as the incrusting material of the plant which is built up mainly, if not entirely, of phenylpropane building stones it carries the major part of the methoxyl content of the wood it is unhydrolyzable by acids readily oxidizable, soluble in hot alkali and bisulfite, and readily condenses with phenols and thio compounds (14). 

Although many suggestions have been advanced for the structure of lignin (15), establishment of a valid constitutional formula for this substance is still far from realized. It was considered (67) that the building stones of lignin are linked together by a methylene dioxv bridge... 

The view that the lignin molecule was made up of building stones with a guaiacyl-syringyl propane skeleton was supported by the brilliant work of Hibbert on ethanolysis and that of Adkins and Harris on the pressure hydrogenation of wood and isolated lignin preparations. 

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