METHODS OF PRODUCING (CYCLOPENTYL[D]PYRIMIDIN-4-YL)PIPERAZINE COMPOUNDS Russian patent published in 2020 - IPC C07D239/26 C07D239/70 C07D241/04 

FIELD: chemistry.

SUBSTANCE: invention relates to organic chemistry and specifically to a method of producing a compound of formula I:

or a salt thereof. Method includes: A. (a) cyclisation of compound VI_b or a salt thereof to form a compound of formula (V), where each X is hydroxyl; (b) bromination of the compound of formula V or a salt thereof with a bromating agent to form a compound of formula IV or a salt thereof, where Y is bromine; (c) reacting a compound of formula IV with a piperazine compound having the structure:

or a salt thereof, where Lv is a leaving group and R¹ is an amino-protecting group, to form a compound of formula III or a salt thereof; B. (d) reacting a compound of formula III with a metallising agent to form a compound of formula I or a salt thereof; where R¹ denotes hydrogen or an amino-protecting group. Also disclosed is a method of producing compound VI_b.

EFFECT: disclosed is a method of synthesis, which is more cost-effective and environmentally friendly, and also reduces probability of formation of by-products.

18 cl, 7 ex