A New, Simple and Efficient Method of Steglich Esterification of Juglone with Long-Chain Fatty Acids: Synthesis of a New Class of Non-Polymeric Wax Deposition Inhibitors for Crude Oil

Gilles, V.; Vieira, Mariana A.; Lacerda, Valdemar; Castro, Eustáquio Vinícius Ribeiro de; Santos, Reginaldo Bezerra dos; Orestes, Ednilson; Carneiro, José Walkimar de M.; Greco, Sandro J.

doi:10.5935/0103-5053.20140216

Cited by 11 publications

(9 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The selective acylation of silybin ( 1 ) (PubChem CID 31553) in position 3-OH to give 3- O -palmitoyl-silybin ( 2 ) was accomplished with the use of palmitic anhydride in the presence of the very oxophilic Lewis acid CeCl 3 ·7H 2 O ( Figure 1 ). This approach was inspired by the work of Gilles et al (2015) [ 19 ] that prepared several alkyl esters of juglone in presence of this Lewis acid and with fatty acids and N , N ′-dicyclohexylcarbodiimide/ N , N -dimethylpyridin-4-amine(DCC/DMAP) as in Steglich esterification.…”

Section: Resultsmentioning

confidence: 99%

“…About 85% of palmitate was found linked in position 3-OH and only 15% in position 5-OH making it not able to decrease the ability to exert its antioxidant activity. The selectivity observed certain results from the very mild operating conditions (ambient temperature, neutral medium) and the exaltation of the electrophilicity of the anhydride by complexation as proposed by Gilles et al (2015) [ 19 ]. Gažák et al [ 12 ], using other catalysts, produced mainly 1 functionalized with palmitate in position 7-OH or 23-OH.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Selective Synthesis of 3-O-Palmitoyl-Silybin, a New-to-Nature Flavonolignan with Increased Protective Action against Oxidative Damages in Lipophilic Media

et al. 2018

View full text Add to dashboard Cite

A selective acylation protocol using cerium chloride (CeCl3) as catalyst was applied to functionalize silybinin (1), a natural antioxidant flavonolignan from milk thistle fruit, in order to increase its solubility in lipophilic media while retaining its strong antioxidant activity. The selective esterification of 1 at the position 3-OH with a palmitate acyl chain leading to the formation of the 3-O-palmitoyl-silybin (2) was confirmed by both mass spectroscopy (MS) and nuclear magnetic resonance (NMR) analyses. The antioxidant activity of 1 was at least retained and even increased with the CUPRAC assay designed to estimate the antioxidant activity of both hydrophilic and lipophilic compounds. Finally, the 3-O-palmitoylation of 1, resulting in the formation of 2, also increased its anti-lipoperoxidant activity (i.e., inhibition of conjugated diene production) in two different lipophilic media (bulk oil and o/w emulsion) subjected to accelerated storage test.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Selective Synthesis of 3-O-Palmitoyl-Silybin, a New-to-Nature Flavonolignan with Increased Protective Action against Oxidative Damages in Lipophilic Media

et al. 2018

View full text Add to dashboard Cite

show abstract

“…After a rigorous literature search, only few examples of phenolic hydroxyl groups direct esterification were found by using Me 2 NSO 2 Cl [ 33 ], montmorillonite-Ti 4+ [ 34 ], metal triflates [ 35 ], TiO(acac) 2 [ 36 ], diarylammonium arensulfate [ 37 ], and tosyl chloride under solvent-free conditions [ 38 ]. Recently, the efficient new methodology of carboxylic acid esterification with phenols was described by the groups of Gilles and Hano [ 39 , 40 ]. The authors performed studies of juglone esterification with different fatty acids using DCC in the presence of DMAP (4-(dimethylamino)pyridine) as a condensation agents (Steglich esterification) with additional Lewis acid as a catalyst (cerium chloride CeCl 3 ).…”

Section: Resultsmentioning

confidence: 99%

Synthesis of Thiol Derivatives of Biological Active Compounds for Nanotechnology Application

et al. 2020

View full text Add to dashboard Cite

An efficient method of thiol group introduction to the structure of common natural products and synthetic active compounds with recognized biological efficacy such genistein (1), 5,11-dimethyl-5H-indolo[2,3-b]quinolin (2), capecitabine (3), diosgenin (4), tigogenin (5), flumethasone (6), fluticasone propionate (7), ursolic acid methyl ester (8), and β-sitosterol (9) was developed. In most cases, the desired compounds were obtained easily via two-step processes involving esterification reaction employing S-trityl protected thioacetic acid and the corresponding hydoxy-derivative, followed by removal of the trityl-protecting group to obtain the final compounds. The results of our preliminary experiments forced us to change the strategy in the case of genistein (1), and the derivatization of diosgenin (4), tigogenin (5), and capecitabine (3) resulted in obtaining different compounds from those designed. Nevertheless, in all above cases we were able to obtain thiol-containing derivatives of selected biological active compounds. Moreover, a modelling study for the two-step thiolation of genistein and some of its derivatives was accomplished using the density functional theory (B3LP). A hypothesis on a possible reason for the unsuccessful deprotection of the thiolated genistein is also presented based on the semiempirical (PM7) calculations. The developed methodology gives access to new sulphur derivatives, which might find a potential therapeutic benefit.

show abstract

“…The synthetic pathway was performed using an amidation reaction (modification of the Steglich reaction 18,19 ) between the corresponding carboxylic acid and the benzylamine with N,N′-dicyclohexylcarbodiimide (DCC), as shown in Scheme 1.…”

Section: Resultsmentioning

confidence: 99%

Synthesis and biological screening of a library of macamides as TNF-α inhibitors

et al. 2020

View full text Add to dashboard Cite

show abstract

A New, Simple and Efficient Method of Steglich Esterification of Juglone with Long-Chain Fatty Acids: Synthesis of a New Class of Non-Polymeric Wax Deposition Inhibitors for Crude Oil

Cited by 11 publications

References 0 publications

Selective Synthesis of 3-O-Palmitoyl-Silybin, a New-to-Nature Flavonolignan with Increased Protective Action against Oxidative Damages in Lipophilic Media

Selective Synthesis of 3-O-Palmitoyl-Silybin, a New-to-Nature Flavonolignan with Increased Protective Action against Oxidative Damages in Lipophilic Media

Synthesis of Thiol Derivatives of Biological Active Compounds for Nanotechnology Application

Synthesis and biological screening of a library of macamides as TNF-α inhibitors

Contact Info

Product

Resources

About