The development of novel inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) represents a viable approach to alleviate Alzheimer's disease. Thirty-six halogenated 2-hydroxy-N-phenylbenzamides (salicylanilides) with various substitution patterns and their esters with phosphorus-based acids were synthesized in yields of 72% to 92% and characterized. They were evaluated for in vitro inhibition of AChE from electric eel and BuChE from equine serum using modified Ellman's spectrophotometric method. The benzamides exhibited a moderate inhibition of AChE with IC50 values in a narrow concentration range from 33.1 to 85.8 µM. IC50 values for BuChE were higher (53.5-228.4 µM). The majority of derivatives inhibit AChE more efficiently than BuChE and are comparable or superior to rivastigmine-an established cholinesterases inhibitor used in the treatment of Alzheimer's disease. Phosphorus-based esters especially improved the activity against BuChE with 5-chloro-2-{[4-(trifluoromethyl)phenyl]carbamoyl}phenyl diethyl phosphite 5c superiority (IC50 = 2.4 µM). This derivative was also the most selective inhibitor of BuChE. It caused a mixed inhibition of both cholinesterases and acted as a pseudo-irreversible inhibitor. Several structure-activity relationships were identified, e.g., favouring esters and benzamides obtained from 5-halogenosalicylic acids and polyhalogenated anilines. Both 2-hydroxy-N-phenylbenzamides and esters share convenient physicochemical properties for blood-brain-barrier penetration and thus central nervous system delivery.

• Keywords
• acetylcholinesterase, benzamides, butyrylcholinesterase, enzyme inhibition, esters, in vitro inhibition, phosphorus derivatives, salicylanilides,
• MeSH
• Acetylcholinesterase metabolism   MeSH
• Benzamides chemistry   pharmacology   MeSH
• Butyrylcholinesterase metabolism   MeSH
• Cholinesterase Inhibitors chemistry   pharmacology   MeSH
• Electrophorus MeSH
• Esters chemistry   pharmacology   MeSH
• Phosphorus chemistry   MeSH
• Inhibitory Concentration 50 MeSH
• Horses MeSH
• Molecular Structure MeSH
• Structure-Activity Relationship MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Acetylcholinesterase MeSH
• Benzamides MeSH
• Butyrylcholinesterase MeSH
• Cholinesterase Inhibitors MeSH
• Esters MeSH
• Phosphorus MeSH

A series of 116 small-molecule 1-hydroxynaphthalene-2-carboxanilides was designed based on the fragment-based approach and was synthesized according to the microwave-assisted protocol. The biological activity of all of the compounds was tested on human colon carcinoma cell lines including a deleted TP53 tumor suppressor gene. The mechanism of activity was studied according to the p53 status in the cell. Several compounds revealed a good to excellent activity that was similar to or better than the standard anticancer drugs. Some of these appeared to be more active against the p53 null cells than their wild-type counterparts. Intercalating the properties of these compounds could be responsible for their mechanism of action.

• MeSH
• Apoptosis drug effects   MeSH
• DNA metabolism   MeSH
• Doxorubicin pharmacology   MeSH
• HCT116 Cells MeSH
• Intercalating Agents pharmacology   MeSH
• Small Molecule Libraries chemistry   pharmacology   MeSH
• Humans MeSH
• Models, Molecular MeSH
• Tumor Suppressor Protein p53 metabolism   MeSH
• Naphthols chemical synthesis   chemistry   pharmacology   MeSH
• Cell Proliferation drug effects   MeSH
• Antineoplastic Agents chemical synthesis   chemistry   pharmacology   MeSH
• Drug Design * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• 1-naphthol MeSH Browser
• calf thymus DNA MeSH Browser
• DNA MeSH
• Doxorubicin MeSH
• Intercalating Agents MeSH
• Small Molecule Libraries MeSH
• Tumor Suppressor Protein p53 MeSH
• Naphthols MeSH
• Antineoplastic Agents MeSH

The resistance among microbes has brought an urgent need for new drugs. Thus, we synthesized a series of Schiff bases derived from the sulfa drug sulfadiazine and various salicylaldehydes. The resulting 4-[(2-hydroxybenzylidene)amino]-N-(pyrimidin-2-yl)benzene-sulfonamides were characterized and evaluated against Gram-positive and Gram-negative bacteria, yeasts, moulds, Mycobacterium tuberculosis, nontuberculous mycobacteria (M. kansasii, M. avium) and their cytotoxicity was determined. Among bacteria, the genus Staphylococcus, including methicillin-resistant S. aureus, showed the highest susceptibility, with minimum inhibitory concentration values from 7.81 µM. The growth of Candida sp. and Trichophyton interdigitale was inhibited at concentrations starting from 1.95 µM. 4-[(2,5-Dihydroxybenzylidene)amino]-N-(pyrimidin-2-yl)-benzenesulfonamide was identified as the most selective Schiff base for these strains with no apparent cytotoxicity and a selectivity index higher than 16. With respect to M. tuberculosis and M. kansasii that were inhibited within the range of 8 to 250 µM, unsubstituted 4-[(2-hydroxy-benzylidene)amino]-N-(pyrimidin-2-yl)benzenesulfonamide meets the selectivity requirement. In general, dihalogenation of the salicylic moiety improved the antibacterial and antifungal activity but also increased the cytotoxicity, especially with an increasing atomic mass. Some derivatives offer more advantageous properties than the parent sulfadiazine, thus constituting promising hits for further antimicrobial drug development.

• Keywords
• Schiff bases, antibacterial activity, antifungal activity, antimycobacterial activity, cytotoxicity, sulfadiazine, sulfonamides,
• MeSH
• Aldehydes chemical synthesis   pharmacology   MeSH
• Anti-Bacterial Agents chemical synthesis   chemistry   pharmacology   MeSH
• Antifungal Agents chemical synthesis   chemistry   pharmacology   MeSH
• Anti-Infective Agents chemical synthesis   pharmacology   MeSH
• Hep G2 Cells MeSH
• Humans MeSH
• Microbial Sensitivity Tests MeSH
• Pyrimidines chemical synthesis   pharmacology   MeSH
• Schiff Bases chemical synthesis   pharmacology   MeSH
• Sulfadiazine analogs & derivatives   chemical synthesis   pharmacology   MeSH
• Cell Survival drug effects   MeSH
• Structure-Activity Relationship MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Aldehydes MeSH
• Anti-Bacterial Agents MeSH
• Antifungal Agents MeSH
• Anti-Infective Agents MeSH
• Pyrimidines MeSH
• salicylaldehyde MeSH Browser
• Schiff Bases MeSH
• Sulfadiazine MeSH

The development of novel antimicrobial agents represents a timely research topic. Eighteen salicylanilide 4-(trifluoromethyl)benzoates were evaluated against Mycobacterium tuberculosis, M. avium and M. kansasii, eight bacterial strains including methicillin-resistant Staphylococcus aureus (MRSA) and for the inhibition of mycobacterial isocitrate lyase. Some compounds were further screened against drug-resistant M. tuberculosis and for their cytotoxicity. Minimum inhibitory concentrations (MICs) for all mycobacterial strains were within 0.5-32 μmol/L, with 4-chloro-2-[4-(trifluoromethyl)phenylcarbamoyl]phenyl 4-(trifluoromethyl)benzoate superiority. Gram-positive bacteria including MRSA were inhibited with MICs ³ 0.49 μmol/L, while Gram-negative ones were much less susceptible. Salicylanilide 4-(trifluoromethyl)benzoates showed significant antibacterial properties, for many strains being comparable to standard drugs (isoniazid, benzylpenicillin) with no cross-resistance. All esters showed mild inhibition of mycobacterial isocitrate lyase and four compounds were comparable to 3-nitropropionic acid without a direct correlation between in vitro MICs and enzyme inhibition.

• MeSH
• Anti-Bacterial Agents pharmacology   MeSH
• Benzoates pharmacology   MeSH
• Nitro Compounds pharmacology   MeSH
• Isocitrate Lyase antagonists & inhibitors   metabolism   MeSH
• Methicillin-Resistant Staphylococcus aureus drug effects   MeSH
• Microbial Sensitivity Tests MeSH
• Mycobacterium avium drug effects   MeSH
• Mycobacterium kansasii drug effects   MeSH
• Mycobacterium tuberculosis drug effects   MeSH
• Propionates pharmacology   MeSH
• Salicylanilides pharmacology   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• 3-nitropropionic acid MeSH Browser
• Anti-Bacterial Agents MeSH
• Benzoates MeSH
• Nitro Compounds MeSH
• Isocitrate Lyase MeSH
• Propionates MeSH
• salicylanilide MeSH Browser
• Salicylanilides MeSH