Phlein

Phlein was acetylated by acetic anhydride in pyridine solution. The crude product was purified by dissolving the dry substance in as small an amount of chloroform as possible, centrifuging to separate impurities, and precipitating the acetate by the dropwise addition of alcohol. After the process had been repeated a few times, a constant-rotating product resulted. 

Methylation was carried out according to the procedure of Haworth and Streight. Trimethylphlein has m. p. 172°, 57.7° 

4-trimethyl-D-fructose resulted accompanied by a small amount of dimethyl-D-fructose which could be accounted for by the slightly low 

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Dimethyl-D-fructose from methylated phlein Dimethyl-D-fructose from methylated liquid — — 188... 

Inulin, levan, graminan, phlein, andkestoses are classified as fructans [12]. Inulin exists either as a linear, branched, or cyclic fructan whereas the structure of the remaining fructans are linear and branched (O Table 2) [13]. 

Asparagosin Asphodelin Graminin Inulin Irisin 300 288 222 360 242 Phlein Secalin Sinistrin Triticin 235 225 269 216... 

Phleins, Levans and Fructans. The strictly p-(2- 6)-linked polymer of fructofuranoside units attached to sucrose is termed phlein. There appear to be no experimental investigations of its structure, although some theoretical work with the primitive AMI basis set suggested a helix for the p-(2- 6)-linked fructofuranose heptamer. ... 

Fructans high-molecular-mass polysaccharides of 1,2- or 1,6-glycosidically linked D-fructose. They are common in plants, e.g. inulin and phlein, and the branched triticin, hordecin and graminin. 

Phlein a high Af, reserve carbohydrate in plants. P. is a straight chain polymer of fructofuranose units joined by 2,6-glycosidic linkages. There is probably a D-glucose unit at the non-reducing end of the chain. 

Not to be confused with AUiumosides (see Furost-5-ene-3,22,26-triol. Isol. from bulbs of Allium sewertzowi. Prod, by reacting levan or phlein with fructosyl transferase from Pseudomonas fluores-cens. Exhibits good heat stability. Shows anticancer activity. Cryst. (EtOH). 

Phlein, P-66 Phleomycin A2, B-40 Phleomycin D2, B-41 Phleomycin Di, B-41 Phleomycin E, B-42 Phleomycin F, B-42 Phleomycin, P-67 Phloroglucite, C-187 Phloroglucitol, C-187 Phosphaden, A-44 Phosphazid, Z-4... 

Fructosans consist predominantly, but not exclusively, of fructose. They are synthesized according to a principle similar to that which we saw, for example, in the case of raffinose. In that case a galactose unit was attached to a primer sucrose molecule. Examination of the structure of the fructosans shows that a large number of fructose units are attached to the fructose component of a sucrose molecule. We shall see presently that the sucrose molecule acts as primer for the biosynthesis. The fructose units can be linked to each other in different ways which makes it necessary to distinguish between the inulin type and the phlein type. 

The phlein type (Fig. 46). The fructose units are linked to each other through 6-2 linkages. Side chains are linked to the main chain through 1-2 linkages. 

Fig. 46. Fructosans Inulin-type (including inulin itself) and phlein-type. Only unbranched chains are shown.

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