Design, synthesis, and biological activity of Schiff bases bearing salicyl and 7-hydroxycoumarinyl moieties

Abstract

18 (11 novel) Schiff bases, derivatives of salicylaldehyde, 2-hydroxyacetophenone, and 6-acetyl-, 8-acetyl-, and 8-formyl-7-hydroxy-4-methylcoumarin were synthesized and characterized by their spectral studies. 6-Acetyl-7-hydroxy-4-methylcoumarin was prepared by novel method under microwave assistance. These Schiff bases were evaluated for antibacterial activities against 12 bacterial and six fungi strains in vitro. N-(3,5-Dichloro-2-hydroxybenzylidene)-4-aminobenzenesulfonic acid sodium salt proved to be the most active against Staphylococcus aureus and MRSA strains (MIC 0.0194 µmol/cm 3). The substitution pattern, two chlorine atoms in the salicylidene ring and the SO 3 Na group, is probably the most beneficial for the activity against Gram-(+) bacteria strains. All Schiff bases were evaluated for cancer efficacy against CFPAC-1 and HeLa cell cultures originating from human pancreas cancer or human cervical cancer. Schiff bases derived from salicylaldehyde are highly effective in pancreas and cervical cancer cells; however, they demonstrate also substantial toxicity towards NIH3T3 cells. Derivatives of coumarin contain three highly selective compounds: 7-hydroxy-8-[(4-methoxyphenylimino)methyl]-4-methyl-2H-chromen-2-one, N-[(7-hydroxy-4-methyl-2-oxo-2H-chromen-8-yl)methylene]-4-aminobenzenesulfonic acid sodium salt, and 7-hydroxy-8-[1-(4-hydroxyphenylimino)ethyl]-4-methyl-2H-chromen-2-one suggesting more promising potential of the second group of substances.

New “one‐pot” Pd(II) and Zn(II) complexes of Schiff bases, derivatives of 1‐amino‐1‐deoxy‐d‐sorbitol: Spectroscopic studies and biological and catalytic activities

“…One of the reasons for the synthesis of new Schiff base complexes, derivatives of amino sugar, was their potential for biological activity . According to Silva et al ., Schiff bases are promising candidates for the design of new antifungal agents.…”

“…The UV-Vis bands of the studied N-(R-salicylidene)-1-amino-1-deoxy-D-sorbitols and their zinc(II) and palladium(II) complexes are presented in Table S3 (supporting information). For ligands, a low energy band T A B L E 1 Selected 13 C and 15 N chemical shifts for compounds studied (1)(2)(3)(4)(5)(6)(7)(8)(9) at~400 nm assigned to the NH form and high energy bands at~300 nm and ca. 260 nm assigned to the OH form were observed.…”

“…Imines are formed as intermediate products in biologically important reactions . Complexes of Schiff bases play an important role in the detection of various ions, exhibit biological properties, and are widely used as catalysts . Recently, several studies focused on Schiff bases and their complexes, derivatives of natural products, for example, amino sugars, amino acids, and chitosan .…”

Coumarin‐containing hybrids and their antibacterial activities

“…Besides the abovementioned coumarin hybrids, coumarin–pyridine hybrids, [ 116–118 ] coumarin–imine hybrids, [ 119–122 ] coumarin–peptide hybrids, [ 123 ] coumarin–indole hybrids, [ 124 ] coumarin–sulfonamide hybrids, [ 125 ] coumarin–ferrocene hybrids, [ 126 ] coumarin–thiazine hybrids, [ 127 ] coumarin–sugar hybrids, [ 128 ] coumarin–pyran hybrids, [ 129 ] and coumarin–glyoxal hybrids [ 130 ] also showed certain antibacterial activity, but the majority of them were far less potent than the reference drugs. Hence, the enriched SAR may pave the way for further rational design of the novel coumarin hybrids.…”

4-Methylumbelliferone And Its Derived Compounds: A Brief Review Of Their Cytotoxicity

“…The antitumor effect of compounds N6-N16 was evaluated against two cancer cell lines, CFPAC (human pancreatic cells) and HeLa (cervical) cells. Four-methylumbelliferonebased derivatives showed higher selectivity for cancer cells than non-malignant cells, with the best anticancer effect exhibited by compounds N8 and N12 [30].…”