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From the hydrolysis products of methylated triticin, tetramethyl fructofuranose (ca. 42%), 1 : 3 : 4-(ca. 11%) and 3 : 4 i 6-trimethyl fructose (ca. 4%), and 3 : 4-dimethyl fructose (ca. 39%) have been separated and identified. A highly branched structure is proposed for the polysaccharide which contains about equal numbers of fructofuranose residues linked by 2 : 1-and 2 : 6linkages.It appears probable that the molecule is built up from ca. 30 fructose residues and that there is no terminal reducing fructose residue. It is suggested that the fructofuranose aggregate is terminated by a glucose residue linked as in sucrose (see Part I, J., 1960Part I, J., , 1297, although the alternative possibility of a closed loop cannot be entirely discounted.SCHLUBACH and SINH (AnnuZen, 1940, 544, 11 1) have suggested that fructosans may be divided into two main groups, namely, the inulin group in which the fructofuranose units are linked through C,,, and C(2,, and the phlein group in which C(2j and C,,, linkages are fundamental. The work of Schlubach and Peitzner (ibid., 1937, 530, 120) appeared to show that the fructosan triticin did not belong to either of these classes.Triticin occurs in the rhizomes of a common weed-type grass Triticum repens L. (Agropyrow repens Beauv.). This species along with others of similar habit is commonly referred to as couch, twitch, quack-grass, etc. These grasses spread freely by means of the creeping rootstocks or rhizomes. The Greeks and Romans appear to have used couch-grass roots as a specific for bladder disorders; some use of this material as an animal feeding stuff has been reported from Scandinavia, and comparative experiments have shown it to have a high nutritive value (Wilson, Nature, 1945, 155, 671).An early attempt to extract a carbohydrate from couch grass is recorded by Stenhouse (J., 1843,2,139) who stated that " the grass roots certainly contain a great deal of uncrystallisable sugar which readily ferments." In 1873 Miiller (Arch. Pharm., 202, 500) gave the name triticin to the gummy carbohydrate which he extracted from powdered couch-grass roots, recorded a specific rotation ([a]D -41' in water), and suggested that it was isomeric with sucrose. Reidemeister (Pharm. 2. fur RussZ. , 1880, 19, 658) made a comparative study of " laevulin," sinistrin

The importance has been assessed of various factors responsible for the release of corrosive vapours from certain freshly‐felled hardwood and softwood species on exposure to high humidity and temperatures in excess of 30°. Variables studied include (i) season of felling, (ii) differences between sapwood and heartwood regions, (iii) initial acid content of the timber on felling, (iv) rǒle of non‐volatile extractive components in catalysing release of corrosive vapours and (v) inhibition of enzymic reactions by mild chemical sterilisation. Although the release of volatile acid is closely related to the loss of bound acetyl groups from the wood substance, indicating autohydrolysis of acetate in the cell wall material, the vapour corrosivity of a timber species is not directly related to its bound acetyl content. The presence of very small free acetic acid contents (0.01—0.03%) in some freshly‐felled undried woods is shown to play a significant rǒle in promoting rapid release of corrosive vapours by the woods (e.g., sweet chestnut and oak). Sterilisation of sweet chestnut and oak with propylene oxide vapour at ambient temperatures markedly reduces, but does not completely eliminate, release of corrosive vapours by these woods. An accompanying reduction in the proportion of bound acetate groups hydrolysed in the cell wall substance may indicate that the release of volatile acidic products from wood is in part due to a microbiological hydrolysis as well as chemical hydrolysis.

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Treatment of beech sawdust with a series of mono-and dicarboxylic acids in benzene solution at 25-30' in the presence of molar proportions of trifluoroacetic anhydride resulted in esterification of the cell wall components. The esterification is shown to be due in part to acylation by the carboxylic acid and in part to trifluoroacetylation. The latter caused discoloration of the wood due to slow hydrolytic release of trifluoroacetic acid on storage at room temperature. Similar esterification of sapwood lengths of Ponderosa pine resulted in surface modification only and was accompanied by a significant decrease in impact strength property.In the presence of increasing concentrations of trifluoroacetic acid liberated during reaction, the acylating power, rather than trifluoroacetylating power, of the acyl trifluoroacetates is enhanced. 7 8The application of this possible method of esterification of the cell wall components of (i) attempted esterification with halogenoalkylmonocarboxylic acids, in the hope of producing a measure of flame-retardant property in addition to dimensional stabilisation and (ii) attempted esterification with dicarboxylic acids to produce an ester-type cross-linkage between adjacent cellulose chains.By the latter method, with trifluoroacetic anhydride and dicarboxylic acid in a molar ratio of 2:1, cross-linkage would be expected to occur by acylation by a di-acylium ion. Thus :wood has been made on two different fronts, viz. :