IMPROVED METHOD OF PRODUCING INTERMEDIATE COMPOUND OF TIGECYCLINE AND METHOD OF PRODUCING TIGECYCLINE THEREFROM Russian patent published in 2024 - IPC C07C231/02 C07C231/12 

FIELD: chemical or physical processes.

SUBSTANCE: invention relates to a method of producing 9-aminominocycline of Formula 1 (C), which is an intermediate compound in synthesis of tigecycline of Formula 1. Method includes steps (01)–(03). At step (01), nitration of minocycline HCl is carried out using HNO₃:H₂SO₄ to obtain 9-nitrominocycline of Formula 1(B). At step (02), 9-nitrominocycline of Formula 1(B) is dissolved in water and pH is adjusted to 6.5–7.5 to obtain a neutral reaction mixture. At step (03), the above mixture reacts with sodium dithionite (Na₂S₂O₄) in solvent for 2–5 hours at temperature of 15–40 °C to obtain 9-aminominocycline of Formula 1(C). Disclosed method is simple, environmentally safe, reliable and easy to implement and enables to overcome the problems of the prior art.

EFFECT: invention also relates to a method of producing tigecycline of Formula 1 using said method.

7 cl, 2 tbl, 7 ex