Synthesis of new pyrazoles, oxadiazoles, triazoles, pyrrolotriazines, and pyrrolotriazepines as potential cytotoxic agents

Abstract

Abstract4‐Oxo‐4‐phenylbutanehydrazide (1) reacted with many active methylene reagents such as acetylacetone, diethylmalonate, ethylacetoacetate, ethylcyanoacetate, benzoyl‐acetonitrile, and malononitrile under neat conditions to afford the corresponding pyrazoles (2–7), also, treatment of butanehydrazide (1) with electrophilic reagents as triethylorthoformate, dimethylformamide‐dimethylacetal, acetic anhydride, and carbon disulfide to give 1,3,4‐oxadiazoles (8,10,11) and N′‐acetyl‐butanehydrazide (9). Reacted of butanehydrazide (1) with potassium thiocyanate gave 1,2,4‐triazoles (12). Similarly, treatment of (1) with chloroacetamide gave 1,2,4‐triazinones (13). The pyrrolotriazinones (14) was obtained by cyclization of (13). Also, butanehydrazide (1) was utilized as a starting material for the synthesized of new Schiff bases as N′‐(4‐sub‐benzylidene)‐phenylbutane‐hydrazide (15a‐c), which are used as an initiative to prepare new compounds such as 1,2,4‐triazepinones (16a‐c), pyrrolotriazepinones (17a‐c), 1,2,4‐triazines (18a‐c), and pyrrolotriazines (19a‐c) by reacted of (15a‐c) with each chloroacetamide or formamide. The chemical structure of the newly prepared compounds was determined through the spectrum data, including IR, NMR, and MS. The prepared compounds were tested for their in vitro antitumor activities. The compounds 17a‐c, 16a‐c, and 19a‐c displayed activity against several types of cancer cell lines.