Synthesis of sulfonate derivatives of carvacrol and thymol as anti-oomycetes agents

Abstract

Two series of sulfonate derivatives of carvacrol and thymol were synthesized and screened in vitro for their anti-oomycete activity against Phytophthora capsici, respectively. Among all of 32 derivatives, five compounds 3a, 4a, 4k, 3n, and 4n exhibited more potent anti-oomycete activity against P. capsici with EC₅₀ values of 66.66, 62.94, 68.65, 61.24, and 52.91 mg/L, respectively. This suggested that introduction of different substitutions at the hydroxyl position of 1/2 could have remarkable effect on anti-oomycete activity. Overall, when R¹ = isopropyl and R² = methyl, the anti-oomycete activities of the compounds were higher than that of the corresponding compounds of R¹ = methyl and R² = isopropyl.

Graphical Abstract

Keywords:

• Natural product
• carvacrol
• thymol
• sulfonylation
• anti-oomycete activity

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was financially supported by Henan Science and Technology Planning Project (Grant No. 202102110068), Natural Science Foundation of Henan Province (Grant No. 182300410043, 182300410016), National Natural Science Foundation of China (Grant No. 31901863).