FIELD: pharmacology. SUBSTANCE: desired derivatives have common formula 
where R is H, C1-C3-alkyl, R1 is H, Cl, Br, CH3; R2 and R3 are H or they form bond; R4 is C1-C4-alkyl, each of R5,R6,R8 and R9 are independently H, or C1-C4-alkyl, R7 is H, C1-C4-alkyl, phenyl, n= 1. Said product is prepared by interaction of compound having formula 
with α-halogen derivative of compound having formula 
, where n, R, R1,R2,R3,R5,R6,R8 and R9 are as mentioned above, R10 and R11 are C1-C4-alkoxy, NHR7 where R7 is as mentioned above, X is halogen, R4 is C1-C4 alkyl or N-protective group. If it is necessary then thus prepared compound is converted into compound 
, the process takes place by heating in vacuum at its melting point or by hydrolysis of carboxylate group COR10 followed by treatment with condensing agent in solvent at 50-450 C. EFFECT: improves efficiency of the method. 4 cl
