* Corresponding author. E-mail address: samy_adjey@yahoo.com (M.A. Gad) © 2021 by the authors; licensee Growing Science, Canada doi: 10.5267/j.ccl.2021.006.001 Current Chemistry Letters 10 (2021) ***–**** Contents lists available at GrowingScience Current Chemistry Letters homepage: www.GrowingScience.com Preparation and biological activity evaluation of some benzoylthiourea and benzoylurea compounds Antar A. Abdelhamid a , A. M. M. Elsaghier a , Safwat A. Aref b , Mohamed A. Gad b* , N. A. Ahmed b and Shaban A. A. Abdel-Raheem c a Department of Chemistry, Faculty of Science, Sohag University, 8252, Sohag, Egypt b Research Institute of Plant Protection, Agricultural Research Center, 12112 Giza, Egypt c Soil, Water, and Environment Research Institute, Agriculture Research Center, Giza, Egypt C H R O N I C L E A B S T R A C T Article history: Received March 20, 2021 Received in revised form May 12, 2021 Accepted June 17, 2021 Available online June 17, 2021 Due to the complicated problems coming from excessive applications of insecticides, searching for safe substitutes to these insecticides has become a necessity. Thus, the insect growth regulators are candidates to be used in such concern. Comparative studies of the effects of three compounds, 2-benzoyl-N-phenylhydrazine-1-carbothioamide (1), 2-(cyanoacetyl)-N- phenylhydrazine-1-carboxamide (2) and N-(2-(2-cyanoacetyl)hydrazinecarbonothioyl)furan-2- carboxamide (3) (an insect growth regulator inhibiting chitin synthesis), were conducted on Spodoptera littoralis (Boisduval, 1833). The compounds, orally administered, caused larval mortality proportional to the concentrations in the food source. larvae were unable to complete the molting process and died in the old larval cuticle. Larvae contaminated by sublethal doses completed their development to adulthood. N-(2-(2-cyanoacetyl)hydrazinecarbonothioyl)furan- 2-carboxamide (3) is more active than the other compounds have LC50 17.082 ppm for 2 nd instar larvae and 60.832 ppm for 4 th instar larvae. © 2021 by the authors; licensee Growing Science, Canada. Keywords: Synthesis Benzoylthiourea and Benzoylurea Insect Growth Regulators Evaluation 1. Introduction Organic compounds are very important in nature due to their different applications. 1-17 Urea and Thiourea its derivatives constitute an important class of heterocyclic compounds which possess wide range therapeutic and pharmacological properties. Sulphonylureas become widely available in 1955 for the treatment of non-ketosis mild diabetes and are still being the drugs of choice. 18 Benzoylurea and benzoylthiourea insecticides have many attractive properties such as high selectivity, 19 high biological activity, rapid degradation in soil and water and the acute low toxicity for animals, which make them suitable for inclusion in integrated pest management programs for crops. 20 On the other hand, many Urea and Thiourea compounds have been developed into insecticide, fungicides, insecticides and other agricultural chemicals. 21 IGRs include juvenile hormone (JH), mimic and chitin synthesis inhibitors (CSIs). 22 CSIs, such as hexaflumuron, lufenuron and diflubenzuron, which inhibit the production of chitin, a major component of the insect exoskeleton. Insects treated with CSIs become unable to synthesize new cuticle, and therefore unable to successfully molt into the next stage. 23 CSIs