Tetracyanoethene and 1‐Amino‐1,2,2‐ethenetricarbonitrile in the Synthesis of Heterocycles of Prospective Antioxidant and Antibacterial

Abstract

Reaction of 1,1,2,2‐ethenetetracarbonitrile (TCNE) with aroyl thioureas in dioxane catalyzed by few drops of piperidine, led to the corresponding 1,2,4‐oxathiazoles. Under the same reaction condition, thiosemicarbazide or thiosemicarbazone reacted with either TCNE or 1‐amino‐1,2,2‐ethene‐tricarbonitrile. The structures of the products were elucidated via NMR, IR, mass spectra, and elemental analyses. The mechanism of formation was discussed. Biological (against Gram‐positive and Gram‐negative bacteria) and antioxidant activities were tested. Some of these heterocyclic compounds showed high activity as antioxidant and antibacterial compounds. The structure–activity relationship was investigated.

Recent developments in chemistry, coordination, structure and biological aspects of 1-(acyl/aroyl)-3-(substituted) thioureas

“…Recently Aly et al revealed the reaction pathway to 1,2,4-oxathiazoles employing the 1,1,2,2-ethenetetracarbonitrile (TCNE) reagent to heterocyclize aroyl thiourea precursors in dioxane (Scheme 7). Biological and antioxidant activities of newly synthesized heterocyclic cores were screened and SAR studies were inspected [38]. The proposed reaction pathway is shown in Scheme 8.…”

N-Naphthoyl Thiourea Derivatives: An Efficient Ultrasonic-Assisted Synthesis, Reaction, and In Vitro Anticancer Evaluations

“…However, such a basic catalyst could also create a carboxylate anion from either chloroacetic acid or the pre-formed thiourea-chloroacetic acid. As a consequence, both the rate of amine–carboxylic acid interaction and reaction yield were remarkably reduced . Interestingly, compound 3 could be also obtained in excellent yield by utilizing ethyl bromoacetate instead of chloroacetic acid (Scheme ).…”

“…As a consequence, both the rate of amine−carboxylic acid interaction and reaction yield were remarkably reduced. 45 Interestingly, compound 3 could be also obtained in excellent yield by utilizing ethyl bromoacetate instead of chloroacetic acid (Scheme 2). In addition, the stereoselective generation of the (Z)-stereoisomer could be explained depending on the allylic strain, as displayed in Figure 1.…”

An Update of the Use of Thiocarbohydrazides and Thiosemicarbazides in the Preparation of Heterocycles and Their Biological Importance

“…Dicyano‐5‐amino‐2,5‐dihydro‐1 H ‐pyrazole‐1‐carbothioamide ( 89a ) was synthetized in 82% yield via interaction between 2 and 1,1,2,2‐tetracyanoethylene (TCNE, 88 ) in 1,4‐dioxane in the presence of a few drops of pyridine under reflux for 6 h (Scheme ) .…”