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Betulin-3,28-dibenzoate and -3,28-diphthalate were synthesized for the first time by reacting betulin with melts of benzoic and phthalic acids at 190–200°C for 5 min.

Betulin was sulfated by sulfamic acid in the presence of urea in homogeneous solution in 1,4-dioxane or N,N-dimethylformamide (DMF). The reaction time for betulin sulfation in DMF at 60–70°C was 2.0–3.0 h; in 1,4-dioxane at 70–75°C, 3.0–3.5 h. Betulin disulfate was obtained in the acidic form and as the ammonium, sodium, and potassium salts.

The catalytic activities of sulfuric acid and of cobalt(II), iron(III), and aluminum sulfates in the thermal splitting of the cellulose and wood of various species in the presence of superheated steam at 250–350°C under flow conditions and at 150–250°C under autoclave conditions have been studied. The yield of levulinic acid from cellulose reaches 35 wt-% and from wood 16.0–18.0 wt-%.

The compositions of the liquid organic products formed from aspen wood and cellulose at 150, 200, and 250° C in the presence of 1, 3, and 5% of HCl, HBr, and H2SO4 have been studied. The yield of levulinic acid from wood reached 13.0–15.5%, and from cellulose 28.8%.

The compositions of the water-soluble substances formed on the thermocatalytic activation of aspen wood under the conditions of explosive autohydrolysis at temperatures of 187, 220, and 240δC and, correspondingly, saturated steam pressures of 1.2, 2.4, and 3.4 MPa have been studied. The water-soluble compounds are formed as the result of hydrolysis reactions of the components of the wood catalyzed by organic acids produced in the decomposition of hemicelluloses. It has been established that the main water-soluble compounds are true sugars, low-molecular-mass lignin, acetic acid, furfural, and sugar degradation products. Methanol, isopropanol, propionic acid, and hydroxymethylfurfural are present in minor amounts. Raising the temperature of the autohydrolysis of wood intensifies the degradation of sugars and increases the degree of their depolymerization to form water-soluble low-molecular-mass fragments.