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P athogens that persist in environmental reservoirs represent a major and underappreciated risk for humans and animals (1). Bacillus anthracis, the causative agent of anthrax, is an extreme example of environmental pathogen persistence because its spores persist for long periods (2), and indirect transmission from environment-to-host is obligate (3). Outbreaks are documented nearly worldwide, and the distribution of disease is constrained by specific environmental conditions (e.g., soil pH, organic matter, calcium) (2,4,5). Outbreaks generally arise in steppe/grassland habitats in wildlife populations (6) and livestock; this pattern was modeled globally (7), nationally (8-13) and locally (14-16) for several regions. The primary hypothesized infection route for livestock/wildlife is ingestion of B. anthracis spores during feeding at 2206

Aims and Objective: 1-Alkynes are the important precursors for the CuAAC click chemistry. The hybrid of 1,2,3-triazole ring to the chromene ring and sugar moiety could bring some remarkable biological properties. Propargyl derivatives are usually used in the click chemistry. This article reported the synthesis of 2-amino-4-aryl-7-propargyloxy-4-aryl-4H-chromene-3-carbonitriles using propargyl bromide as alkylation agent and the use of potassium carbonate and sodium hydride as bases in the conversion of 2-amino-4-aryl-7- hydroxy-4-aryl-4H-chromene-3-carbonitriles into corresponding propargyl ethers in Williamson’s ether synthesis. Materials and Methods: The use of CTAB for the synthesis of benzylidene malononitriles and anhydrous potassium carbonate as a catalyst in absolute ethanol in the synthesis of 2-amino-7-hydroxy-4H-chromene-3- carbonitriles is an efficient and simple synthetic method. Propargyl ether compounds of these 4H-chromene-3- carbonitriles were obtained from the alkylation reaction by propargyl bromide. Two procedures were applied: K2CO3 as a base in acetone solvent (Procedure A) and NaH as a base in DMF solvent (Procedure B). The single-crystal X-ray structure of propargyl ether 5e has been studied. Results: The use of K2CO3 and NaH as bases in the Williamson’s ether synthesis from 2-amino-7-hydroxy-4Hchromene- 3-carbonitriles showed that Procedure B was the better route and gave ethers in the higher yields. 2- Amino-4-aryl-7-propargyloxy-4-aryl-4H-chromene-3-carbonitriles were obtained from corresponding 7- hydroxy-4H-chromene-3-carbonitriles. Yields of ethers 5a-i were 70−89% and 80−96%, respectively depending on the used procedures. Conclusion: The described methods are simple, clean and environmentally friendly alternatives for the preparation of 2-amino-4-aryl-7-hydroxy-4H-chromene-3-carbonitriles. The conditions for the transformation of these compounds into propargyl ethers include dried DMF as a solvent, NaH as a base and reaction time of 2 h at the room temperature. A series of 2-amino-4-aryl-7-hydroxy-4-aryl-4H-chromene-3-carbonitriles were obtained based on investigated reaction condition.