METHOD FOR PREPARING HYDROXYINDOLYLGLYOXYLAMIDES OF HIGH PURITY Russian patent published in 2008 - IPC C07D401/12 C07D209/30 

FIELD: organic chemistry, chemical technology.

SUBSTANCE: invention relates to a method for synthesis of hydroxyindolylglyoxylamides of the formula (1) wherein R means linear or branched (C₁-C₆)-alkyl that can be if necessary substituted once with monocyclic saturated or polyunsaturated carbocycle comprising 3-14 members in cycle wherein carbocyclic substitute, in turn, can be substituted once or more times with the following groups: -OH, -NO₂, -F, -Cl, -Br, -J, -O-(C₁-C₆)-alkyl; R² and R³ mean hydrogen atom or -OH and it is necessary that one of two substitutes has to mean -OH; R⁴ means monocyclic aromatic carbocycle comprising 6-14 members in cycle or pyridyl and if necessary substituted once or more times with the following groups: -F, -Cl, -Br, -J, -O-(C₁-C₆)-alkyl or -(C₁-C₆)-alkyl wherein each (C₁-C₆)- alkyl radical can be substituted once or more times with the following groups: -F, -Cl, -Br, -J. Proposed method involves the following steps: (a) interaction of the parent compound of the formula (1a) wherein R² and R³ mean hydrogen atom or benzyl-protected -OH and it is necessary that at least one of two substitutes has to mean benzyl-protected -OH with compound of the formula: R¹-X wherein R¹ means above given values, and X means halogen atom resulting to formation of compound of the formula (1b) ; (b) interaction of compound of the formula (1b) with compound of the formula: (COX)₂ wherein X means halogen atom resulting to formation of compound of the formula (1c) ; (c) interaction of compound of the formula (1c) with compound of the formula: H₂NR wherein R has values as given for R⁴ and resulting to formation of compound of the formula (1d) , and (d) interaction of compound of the formula (1d) involving splitting off benzyl from R² and/or R³ and resulting to formation of the end compound of the formula (1). Also, invention relates to intermediate compounds of formulae (1c) and (1d) and using compounds of formulae (b), (1c) and (1d) for synthesis of the end compounds of the formula (1). Proposed invention provides synthesis of the end compounds of the formula (1) with the high yield and in high pure form.

EFFECT: improved method of synthesis.

25 cl, 1 ex