FIELD: medicine.SUBSTANCE: present invention relates to a medicinal hyaluronic acid derivative containing a unit of formula (I):where R1–R4 are selected from H, C1-6alkyl, formyl and C1-6alkylcarbonyl； R5 is selected from H, formyl or C1-6alkylcarbonyl； R6 is selected from H and C1-6alkyl； -CHRa-CO-X1 is selected from groups: , , where * denotes the site of attachment to -NR6-； Z1 is C2-30alkylene or -(CH2CH2O)m-CH2CH2- optionally containing 1–5 groups -O-, -NRg- or -S-S-； m is 1–100； Z2 selected from -NRb-Z3 and -NRb-COO-Z3； Rb is selected from H, C1-20alkyl, amino-C2-20alkyl and hydroxy-C2-20alkyl optionally containing 1–3 groups -O- and -NRf-； Rf is selected from H, C1-12alkyl, amino-C2-12alkyl and hydroxy-C2-12alkyl optionally containing 1 to 2 groups -O- or -NH-； Rg is selected from H, C1-20alkyl, amino-C2-20alkyl or hydroxy-C2-20alkyl optionally containing 1–3 groups -O- or -NH-； Z3 – cholanoyl or cholesteryl； and for X1, other than -NR9-Z1-Z2, said derivative additionally contains a unit of formula (II): where R1a–R4a are selected from H, C1-6alkyl, formyl and C1-6alkylcarbonyl； R5a is H, formyl or C1-6alkylcarbonyl； X2 is -NH-Z1-Z2, where Z1 and Z2 are defined above； and said derivative is obtained using hyaluronic acid exclusively consisting of units of formula (IIb): where R5b is selected from H, formyl and C1-6alkylcarbonyl； Xb is selected from OH and -O-Q+, where Q+ selected from Li+, Na+, Rb+, Cs+, Mg2+, Ca2+, N+RjRkRlRm, where Rj, Rk, Rl and Rm are selected from H and C1-6alkyl having molecular weight from 3 kDa to 1,500 kDa, when R1b–R4b all represent H, R5b is acetyl, and Xb represents -O-Na+.EFFECT: novel compound, effective for encapsulating drugs, and a pharmaceutical composition based thereon are disclosed.11 cl, 9 ex, 22 tbl, 119 dwgНастоящее изобретение относится к пригодному в медицине производному гиалуроновой кислоты, содержащему единицу формулы (I):где R1-R4 выбраны из H, С1-6алкила, формила и С1-6алкилкарбонила； R5 выбран из H, формила
