A New Approach to the Synthesis of Vicinal Diol Derivatives from Eugenol and Evaluation of Biological Activities of Synthetics

Abstract

The vicinal diol derivatives of eugenol were synthesized using the following steps: esterification with acid anhydrides/pyridine, followed by oxidation with KMnO₄ in a cold, dilute acetone/NaOH medium. The intermediate 4-allyl-2-methoxyphenyl acetate (EA) and the vicinal diol derivative 4-(2,3-dihydroxypropyl)-2-methoxyphenyl acetate (DIO) were synthesized with 97% and 43% yields, respectively. The byproduct of the EA oxidation reaction was identified as 4-acetoxy-3-methoxybenzaldehyde (ALD). Synthetic substances were investigated for biological activities, including antioxidant, antibacterial, and α-glucosidase inhibition. The antioxidant activity of EA, ALD, and DIO was modest, with %RSA₅₀ values exceeding 6666.67 µg/ml, 1174.53 µg/ml, and 59.47 µg/ml, respectively. Regarding antibacterial activity, EA exhibited antibacterial activity against MSSA (MIC = 256 µg/ml), and DIO could be active against Streptococcus pyogenes (MIC = 1024 µg/ml). While EA and DIO inhibited α-glucosidase with limited activity (at a screening concentration of 0.5 mg/ml, inhibition levels were 12.19 ± 6.83% and 43.98 ± 2.34%, respectively), ALD showed potential (with an IC₅₀ of 0.27 mg/ml). Research indicates that eugenol derivatives have potential as antibacterials and α-glucosidase inhibitors.