Antileishmanial and Cytotoxic Compounds from Valeriana wallichii and Identification of a Novel Nepetolactone Derivative

• Main Authors: Jan Glaser, Martina Schultheis, Heidrun Moll, Banasri Hazra, Ulrike Holzgrabe
• Format: Article
• Language: English
• Published: MDPI AG 2015-04-01
• Series: Molecules
• Subjects: V. wallichii; antileishmanial; cytotoxicity; podophyllotoxin; valtrates; novel nepetolactone derivative
• Online Access: http://www.mdpi.com/1420-3049/20/4/5740

The chloroform extract of Valeriana wallichii (V. wallichii) rhizomes was investigated to elucidate the structures responsible for reported antileishmanial activity. Besides bornyl caffeate (1, already been reported by us previously), bioassay-guided fractionation resulted in two additional cinnamic acid derivatives 2–3 with moderate leishmanicidal activity. The structure of a novel nepetolactone derivative 4 having a cinnamic acid moiety was elucidated by means of spectral analysis. To the best of our knowledge villoside aglycone (5) was isolated from this plant for the first time. The bioassay-guided fractionation yielded two new (compounds 6–7) and two known valtrates (compounds 8–9) with leishmanicidal potential against Leishmania major (L. major) promastigotes. In addition, β-bisabolol (10), α-kessyl alcohol (11), valeranone (12), bornyl isovalerate (13) and linarin-2-O-methylbutyrate (14) were identified. This is the first report on the isolation of 4'-demethylpodophyllotoxin (15), podophyllotoxin (16) and pinoresinol (17) in V. wallichii. In total thirteen known and four new compounds were identified from the extract and their cytotoxic and antileishmanial properties were evaluated.