1,2,3-triazol 1,3-oxazines 1-oxa-triene 1H-imidazole-2(3H)-thione 2H-imidazo[2,1-b][1,3,4]thiadiazine 2H-pyran 3,2':6',3"-terpyridine 3-trifluoroacetyl coumarins 4-bromo quinolines 5-acylamino-1,3-thiazoles CF3CO-acetylenes CuAAC Hantzsch reaction Knoevenagel Medicine Richter cyclization Staudinger reaction Suzuki coupling TMSBr acylhydrazone group alkynes alkynoic acids amine nucleophiles antifungal activities antitumor aromatic substitution arylation asymmetric dimeric β-carboline aza-Wittig azides