Antioxidants Effect of Two Aminomethyl Derivatives of 2-Methoxyphenol on Thermal and Storage Oxidative Stability of Coconut Oil

The antioxidants effect of two aminomethyl derivatives of 2-methoxyphenol: 4,6-di[(morpholin-4-yl)methyl]-2-methoxyphenol (DMMMP) and 5-[(pyrrolidin-1-yl)methyl]vanillic acid (PMVA) on enhancing thermal and oxidative storage stability of coconut oil was performed using tert-butylhydroxyquinone (TBHQ) as a comparative standard. The efficacy on thermal stability test was carried out by heating at 180 oC for 1, 3, and 6 hours, while the efficacy on the storage stability test was performed using an accelerated method by heating at 60oC for 5 weeks. The concentrations for MDMMP was 200, 350, and 500 ppm; for PMVA was 200, 275, and 350 ppm; and for TBHQ was 200 ppm. Free fatty acid (FFA) level, peroxide value (PV), and p-anisidine value (p-AV) were used as parameters to assess the level of oxidative stability of coconut oil. The results showed that the addition of DMMMP 200, 350, and 500 ppm, and PMVA 200 and 275 ppm did not inhibit FFA, peroxide, and aldehyde formation. In thermal stability study, PMVA (350 ppm) could inhibit the free fatty acid release, and formation of secondary oxidation products compounds on thermal stability comparable to TBHQ (200 ppm) addition, but only TBHQ that could inhibit peroxide formation for 6 h. In storage stability, DMMMP (all concentration) could not delay the fatty acid release, while PMVA (all concentration) and TBHQ (200 ppm) delayed that for 2 and 5 weeks, respectively. DMMMP (all concentration) delayed peroxide formation for 2 weeks, while PMVA (all concentration) and TBHQ (200 ppm) delayed peroxide formation for 5 weeks. All compounds only delay the formation of secondary oxidation products for 1 week. In conclusion, the efficacy of PMVA as an antioxidant against thermal and storage oxidative stability of coconut oil is higher than DMMMP but lower than TBHQ.

SYNTHESIS OF ETHYL ETHER OF 4(4-HYDROXYPHENYL)- AND 4′-METHYL-4(4-HYDROXYPHENYL)CYCLOHEXANCARBONIC ACIDS AND THEIR AMINOMETHYLATED DERIVATIVES

The article presents the results of cycloalkylation of phenol with ethyl cyclohexane- and 4-methylcyclohexenecarboxylic esters in the presence of a zeolite-Y catalyst impregnated with phosphoric acid. It has been established that to perform the cycloalkylation of phenol with ethyl cyclohexenecarboxylic acid in the presence of a zeolite-Y catalyst impregnated with orthophosphoric acid, the optimal conditions are: temperature 120 °С, reaction time 5 h, molar ratio of phenol to ether 1 : 1 mol/mol. And amount of catalyst is 10% for taken phenol. The yield of the target product was 74.7% of the theory for taken phenol, and selectivity - 93.8% for the target products. It was found that under optimal reaction conditions cycloalkylation (temperature 110 °C, reaction time 4 h, the ratio of phenol to ether 1 : 1, the amount of catalyst 7%) of phenol with ethyl 4-methylcyclohexenecarboxylic acid yield of ethyl 4 (4-hydroxyphenyl) -4'-methylcyclohexane-carboxylic) acid was 78.3% of the theory per phenol taken, and the selectivity was 95.7% for the desired product. The synthesis of aminomethyl derivatives of 4-hydroxyphenylcyclohexanecarboxylic acids in the presence of formalin and aniline was also carried out. As a result of aminomethylation, ethyl esters of 4 (4-hydroxy-3-phenylaminobenzyl) cyclohexane- and 4 (4-hydroxy-3-phenylaminobenzyl) -4'-methylcyclohexanecarboxylic acid were obtained. The yields of the target products were 67.3 and 71.7%, respectively, from the theory on taken ether. The structure and composition of the products were determined using IR and 1H NMR spectroscopy. And the purity of the products obtained was studied by chromatographic analysis. Ethyl esters of 4 (4-hydroxy-3-phenylaminobenzyl) cyclohexane- and 4 (4-hydroxy-3-phenylaminobenzyl) -4'-methylcyclohexanecarboxylic acid can be used as an antioxidant to diesel fuel and turbine oil T-46.

Synthesis and Anti-inflammatory Activity of 2-Methoxy-4-(1-phenyl-3- methyl-1H-pyrazol-5-yl)phenol) and Its Aminomethyl Derivatives

Using heat-induced protein denaturation technique, a series of novel synthesized 1,5-diarylpyrazole compounds, namely 2-methoxy-4-(1-phenyl-3-methyl-1H-pyrazol-5-yl)phenol (1) and its aminomethyl derivatives (2a-e) were evaluated for their anti-inflammatory potentiality. The structures of the synthesized compounds were elucidated using FTIR, NMR (1H & 13C) and mass spectral data. The study found that the activity of aminomethyl derivatives (2a-e) was higher than that of parent compound 1. In this series, aminomethyl derivatives bearing dimethylamino-methyl, diethylaminomethyl and pyrrolidinomethyl moieties (2a, 2c and 2e, respectively) were more active than diclofenac sodium, which was used as a standard. A study on the structure-activity relationship (SAR) suggested that the activity of aminomethyl moiety of the compound was influenced by its pKa value. Thus, novel compounds act as potential anti-inflammatory agents.

Synthesis and transformation of 6-aminomethyl derivatives of 7-hydroxy-2'-fluoroisoflavones

Mannich aminomethylation of 8-methyl-7-hydroxy-2'-fluoroisoflavones applying bis-(N,N-dimethylamino)methane afforded C-6 substituted N,N-dimethylaminomethyl derivatives. Subsequent acetylation of these compounds in acetic anhydride in the presence of potassium acetate provided access to the corresponding acetoxymethyl derivatives that were converted to hydroxymethyl- and alkoxymethyl-substituted 7-hydroxyisoflavonoids. Addition of 3-(N,N-dimethylamino)-5,5-dimethyl-2-cyclohexen-1-one or 1,3-dimethyl-5-aminopyrazole with thermally generated ortho-quinone methides led to hetero-Diels–Alder or Michael adducts.