The best replacement for esters is ethers.

The best alternatives to esters are rated as following:
★★★★★  ethers
★★★  lutein
★★★  amides
★★  triglycerides
★★  cholesterol
★★  free lutein
★  amino amides
★  thioesters
★  esters
★  phenols
  ketones

Your alternative for esters is not listed? Suggest!
Speaking about esters, one probably shouldn't forget about grignard reagents.

Other search terms related to esters and their ratings are:
★★★★★ grignard reagents
★★★★★ lialh4
★ thionyl chloride
You have in mind a companion for esters and it is not yet here? Propose!



Google Trends

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esters
ethers
lutein