Hydroxy acid compound of substituted phenyl ester, preparation method andmedical use thereofare provided. The title compound is shown in formula (I), Y = C1-4 straightcarbon chain. Thecompound can release 2, 6-diisopropylphenol rapidly under the action ofenzymes in vivo, whichhas sedative, hypnotic and/or anesthetic effect. By protecting the hydroxylgroup of 2,6-diisopropylphenol in compound of formula (I), the first-pass metabolicactivity of 2,6-diisopropylphenol is reduced, so that the synthetic compound can be used forsedation,hypnosis, and/or anesthesia.(See Formula I)