Abstract
A series of novel coumarin derivatives were synthesized from 6-hydroxy-7-methoxy-4-methyl coumarin which was isolated from the aerial parts of the Egyptian medicinal plant
Ammi majus
L. (Apiaceae). The key intermediate 3-amino-5-methoxy-1-(4-methoxyphenyl)-10-methyl-8-oxo-1,8-dihydropyrano[3,2-
f
]chromene-2-carbonitrile (
3c
) was obtained in one-pot synthesis by treating α-cyanocinnamonitrile (
1-c
) with the natural compound: 6-hydroxy-7-methoxy-4-methyl coumarin (
2
). Chemical, elemental and spectroscopic evidences confirmed the structures of the synthesized compounds. Some of the newly synthesized compounds exhibited better anti-inflammatory activities at low concentrations compared with indomethacin as positive control.