Hydroxy acid compound of substituted phenyl ester preparation method and medical use thereof are provided. The title compound is shown in formula (I) Y = C1-4 straight carbon chain. The compound can release 2 6-diisopropylphenol rapidly under the action of enzymes in vivo which has sedative hypnotic and/or anesthetic effect. By protecting the hydroxyl group of 2 6-diisopropylphenol in compound of formula (I) the first-pass metabolic activity of 2 6-diisopropylphenol is reduced so that the synthetic compound can be used for sedation hypnosis and/or anesthesia.
