SYNTHESIS OF SPIRO COMPOUNDS WITH 3-METHYL-2-AZAFLUORENE, INDAN, PYRAZOLINE, AND CYCLOPROPANE FRAGMENTS ON THE BASIS OF 3-METHYL-9-PHENYLETHYNYL-2-AZAFLUOREN-9-OL ArticleProstakov N.S., Makuli M., Mikhailova N.M., Abubakr H., Sergeeva N.D., Obynochnyi A.A.Chemistry of Heterocyclic Compounds. Vol. 21. 1985. P.. 449-452