A novel sesquiterpene and three new phenolic compounds from the rhizomes of Acorus tatarinowii Schott.

A novel sesquiterpene with an unprecedented epoxy lactone skeleton, named tatarinolactone, together with two new amides, a new biphenylpropanoid and two known lignans were isolated from the rhizomes of Acorus tatarinowii Schott. Their structures were identified as 6,7,8-trihydroxy-4α-isobutyl-4,7-dimethylhexahydro-6,8α-epoxychromen-2(3H)-one (1), (E)-methyl 4-[3-(4-hydroxy-3-methoxyphenyl)acrylamido]butanoate (2), (Z)-methyl 4-[3-(4-hydroxy-3-methoxyphenyl)acrylamido]butanoate enol isomer (3), (R)-4-hydroxy-3-[1-hydroxy-3-(4-hydroxy-3-methoxyphenyl)propan-2-yl]-5-methoxybenzoic acid (4), (2S,3R)-ceplignan (5), and (2R,3S)-ceplignan (6), respectively, based on extensive spectroscopic analysis and by comparison to the known compounds. To test their effects on serotonin transporters, a high content assay using hSERT-HEK293 cell line was adopted. Results indicated that compounds 1 and 4 significantly inhibited SERT activity, while compounds 2, 3, 5, and 6 significantly enhanced SERT activity, which partly explain the traditional uses of the rhizomes of Acorus tatarinowii Schott in treatments of neuropsychiatric and digestive disorders.