Synthesis, Thermolysis, Novel Semicarbazones And...

Synthesis, Thermolysis, Photolysis and Animicrobial Evaluation of some Novel Semicarbazones and Thiosemicarbazones Derived from 3-Methyl-2-benzothiazolinone Hydrazone. Hisham Abdallah A. Yosef * and Nabila M. Ibrahim Department of Organometallic and Organometalloid Chemistry, National Research Centre, El-Behouth Street, P.O. 12622, Dokki, Giza, Egypt. Abstract: Reaction of 3-Methyl-2-benzithiazolinone hydrazone (1) with some seleceted isocyanate and isothiocyanate reagents 2a−j gave the respective semicarbazones and thiosemicarbazones 3a−j. Thermolysis of compound 3a under reduced pressure gave N,N`−dietylurea (4) in addition to 1,2-bis(3-methylbenzo[d]thiazol-2(3H)-ylidene)hydrazine (5). Compound 3a was almost quantitatively recovered upon its exposure to sunlight in methanol for 60 days. Elementary and spectroscopic measurements (IR, 1H NMR, 13C NMR, MS) are in good accord with the structures postulated for the new compounds. The single crystal X-ray crystallographic analysis of 3f was given and its data were discussed. The synthesized compounds 3a-j as well as the hydrazone 1 were screened for their antibacterial properties against Bacillus subtilis (G+), Escherichia coli (G-), Pseudomonas aeruginosa (G-) and Staphylococcus aureus (G+) and for their antifungal properties against Aspergillus flavus and Candida albican s. Some of the tested compounds showed an activity against the four bacterial strains where their order of activity was found to be 1 3g 3j 3i 3e