ARYLHYDRAZONES OF Α-KETO ESTERS VIA METHANOLYSIS OF DICHLORODIAZABUTADIENES: SYNTHESIS AND STRUCTURAL STUDY Article Shikhaliyev N.G., Maharramov A.M., Suleymanova G.T., Babazade A.A., Nenajdenko V.G., Khrustalev V.N., Tskhovrebov A.G., Novikov A.S. Mendeleev Communications. Royal Society of Chemistry. Vol. 31. 2021. P. 677-679