105954-99-2

Upstream product

• 100-52-7 benzaldehyde 
• 140-10-3 (E)-3-phenylacrylic acid 
• 51-61-6 dopamine 
• 62-31-7 dopamine hydrochloride 
• 102-92-1 Cinnamoyl chloride 
• 2757-02-0 C₄H₉C₂O₄C₂H₂C₆H₅ 

Relevant academic research and scientific papers

Anti-tyrosinase, antioxidant and antimicrobial activities of hydroxycinnamoylamides

Synthetic hydroxycinnamoylamides of amino acids (precursors of aromatic amines) were studied for their antioxidant activity in vitro by two antioxidant assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and inhibition of lipid peroxidation (LPO). Furthermore, these compounds were tested and compared with their corresponding cinnamoylamides of aromatic amines for their inhibitory activity using mushroom tyrosinase. In addition, five hydroxycinnamoyl amino acid amides were investigated for their antimicrobial effect. Structure-activity relationships analysis disclosed that the presence of catechol rest at amino acid or at benzene moieties of substituted cinnamic acid amides significantly scavenged DPPH radical and inhibited LPO. The results obtained by LPO clearly expressed the positive influence of indole moiety on the activity. Moreover, the existence of p-hydroxy substituted cinnamic acid moiety leads to better tyrosinase inhibition. Amongst the tested compounds, amides of p-coumaroyldopamine or tyramine and their corresponding amino acid precursors are the most potent tyrosinase inhibitors.

Synthesis and structure-activity relationships and effects of phenylpropanoid amides of octopamine and dopamine on tyrosinase inhibition and antioxidation

Phenylpropanoid amides of octopamine (OA) 1a-1e and dopamine (DA) 2a-2e were synthesised and the structure-activity relationships (SARs) for antioxidant and tyrosinase inhibition activities were analysed. Among synthesised compounds, 2c, which contains two catechol moieties, exhibited the most DPPH radical-scavenging activity (EC50 = 16.2 ± 2.4 μM), and 1d exhibited significant tyrosinase inhibitory activity (IC50 = 5.3 ± 1.8 μM). Interestingly, with the same acid moiety, OA derivatives showed more inhibitory effect on tyrosinase than did compounds derived from DA, whereas DA derivatives were found to have higher antioxidant activity than compounds derived from OA. The relationship between their structures and their potencies, demonstrated in the current study, will be useful for the design of optimal agents.

N-Caffeoylphenalkylamide derivatives as bacterial efflux pump inhibitors

As part of an ongoing project to identify plant natural products as efflux pump inhibitors (EPIs), bioassay-guided fractionation of the methanolic extract of Mirabilis jalapa Linn. (Nyctaginaceae) led to the isolation of an active polyphenolic amide: N-trans-feruloyl 4′-O-methyldopamine. This compound showed moderate activity as an EPI against multidrug-resistant (MDR) Staphylococcus aureus overexpressing the multidrug efflux transporter NorA, causing an 8-fold reduction of norfloxacin MIC at 292 μM (100 μg/mL). This prompted us to synthesize derivatives in order to provide structure-activity relationships and to access more potent inhibitors. Among the synthetic compounds, some were more active than the natural compound and N-trans-3,4-O-dimethylcaffeoyl tryptamine showed potentiation of norfloxacin in MDR S. aureus comparable to that of the standard reserpine.

A novel [2 + 2] photodimerization of N-[(E)-3,4-methylenedioxycinnamoyl]dopamine in the solid state.

[reaction: see text] To give photoreactivity to catecholamines, N-cinnamoyl-substituted dopamines (E)-5a-5c and O,O'-dimethyldopamines (E)-3a-3c were prepared under solvent-free conditions. A particularly interesting observed photoreactivity was that of N-[(E)-3,4-methylenedioxycinnamoyl]dopamine ((E)-5c), which underwent a novel type of [2 + 2] photodimerization in the solid state, giving exclusively a tricyclic product 8. This reaction is the first example of solid-state photoaddition of an alkene to the benzene ring.

Inhibition of in vitro prostaglandin and leukotriene biosyntheses by cinnamoyl-β-phenethylamine and N-acyldopamine derivatives

N-trans- and N-cis-Feruloyltyramines were isolated as the inhibitors of in vitro prostaglandin (PG) synthesis from an Indonesian medicinal plant, Ipomoea aquatica (Convolvulaceae). In order to clarify structure activity relationships, cinnamoyl-β-phenethylamines with possible combinations of naturally occurring cinnamic acids and β-phenethylamines were synthesized and tested for their inhibitory activities against PG synthetase and arachidonate 5-lipoxygenase. The compounds containing catechol groups such as N-caffeoyl-β-phenethylamine (CaP) showed higher inhibitory effects on PG synthetase. The catechol group was found to M essential for the inhibition of arachidonate 5-lipoxygenase. The investigation of concentration dependent effects on PG biosynthesis revealed that CaP enhanced PG biosynthesis at a lower concentration range, whereas it inhibited the reaction at a higher concentration. The effects of CaP on each reaction step were investigated with purified PG endoperoxide synthase and microsomal PG synthetase. CaP inhibited the cyclooxygenase reaction, while it enhanced the hydroperoxidase reaction. N-Acyldopamines which contain catechol and lipophylic group were synthesized from dopamine and fatty acids to test their inhibitory effects on arachidonate 5-lipoxygenase. N-Linoleoyldopamine was the most active compound and its IC50 value was 2.3 nM in our assay system, in which an IC50 value of AA 861, a specific inhibitor of 5-lipoxygenase, was 8 nM.