Vu Ngoc Toan*, Nguyen Minh Tri and Nguyen Dinh Thanh* Pages 2272 - 2282 ( 11 )
Several 6- and 7-alkoxy-2-oxo-2H-chromene-4-carbaldehydes were prepared from corresponding alkyl ethers of 6- and 7-hydroxy-4-methyl-2-oxo-2H-chromen-2-ones by oxidation using selenium dioxide. 6- and 7-Alkoxy-4-methyl-2H-chromenes were obtained with yields of 57-85%. Corresponding 4-carbaldehyde derivatives were prepared with yields of 41-67%. Thiosemicarbazones of these aldehydes with D-galactose moiety were synthesized by reaction of these aldehydes with N-(2,3,4,6-tetra-O-acetyl-β-Dgalactopyranosyl) thiosemicarbazide with yields of 62-74%. These thiosemicarbazones were screened for their antibacterial and antifungal activities in vitro against bacteria, such as Staphylococcus aureus, Escherichia coli, and fungi, such as Aspergillus niger, Candida albicans. Several compounds exhibited strong inhibitory activity with MIC values of 0.78- 1.56 μM, including 8a (against S. aureus, E. coli, and C. albicans), 8d (against E. coli and A. niger), 9a (against S. aureus), and 9c (against S. aureus and C. albicans).
2H-Chromen-2-ones, 2H-chromene-4-carbaldehydes, antibacterial, antifungal, ethyl acetoacetate, D-galactose, thiosemicarbazide, thiosemicarbazone.
Institute for Chemistry and Materials, Vietnam Academy of Military Science and Technology, 17 Hoang Sam, Cau Giay, Ha Noi, Institute for Chemistry and Materials, Vietnam Academy of Military Science and Technology, 17 Hoang Sam, Cau Giay, Ha Noi, Faculty of Chemistry, VNU University of Science (Vietnam National University, Ha Noi), 19 Le Thanh Tong, Hoan Kiem, Ha Noi