Three New Diterpenoids from the Fruit of Vitex agnus-castus

Abstract

Three new labdane-type diterpenoids, viteagnusins F, G, and H, were isolated from the hexane extract of fruit (chasteberry) of Vitex agnus-castus L. (Verbenaceae) along with seven known compounds including four labdane-type diterpenoids, one norlabdane-type diterpenoid, one aromadendrane-type sesquiterpenoid, and one flavonoid. The chemical structures of the three new labdane-type diterpenoids were determined on the basis of spectroscopic data as well as chemical evidence.

Phytoconstituents from Vitex agnus-castus fruits

“…When comparing our data for 1 with data from the literature, the NMR spectroscopic fingerprint ( 1 H and 13 C) was similar to that of viteagnusin H ( 2 , Fig 1), a labdane-type diterpene recently isolated from a hexane extract of VAC fruits [11]. However, as the high-resolution mass spectrometric data had indicated, 1 has 22 carbons and contained one CH 2 less than 2 , which was consistent with the lack of a methoxyl group attached to C-16.…”

“…All these NMR evidences suggested compound 1 should be an acetylated diterpene. According to the reported diterpenes from Vitex genus in the literature [9–11], 1 should have a labdane skeleton.…”

“…Currently, the fruit extract is used as a dietary supplement for estrogen hormone imbalance which can produce menstrual cycle disorders and premenstrual syndrome (PMS), such as cyclical mastalgia, and corpus luteum insufficiency [1,2] as well as for alleviating menopausal symptoms such as hot flashes [3]. The classes of phytochemicals that have been reported in VAC fruits include essential oils [4,5], flavonoids [6,7], iridoids [8], and diterpenoids [9–11], as well as a diterpene lactam, vitexlactam A [12]. Under investigation for safety and efficacy at the UIC/NIH Center for Botanical Dietary Supplements Research, preliminary screening of a methanolic extract of VAC showed it contained ligands for the estrogen receptor (ER) [3].…”

Three new diterpenoids from Marrubium aschersonii

“…Analysis the 1 H and 13 C NMR data of 2 with those of viteagnusin G, a known labdane-type diterpenoid previously reported (Ono et al, 2009), showed that 2 had the same skeleton type as the known. The differences between them were that the acetoxyl group at C-6 and a methyl in viteagnusin G were disappeared in 2 instead of a hydroxyl group and a hydroxymethyl, respectively.…”

Identification of New Diterpenes as Putative Marker Compounds Distinguishing Agnus Castus Fruit (Chaste Tree) from Shrub Chaste Tree Fruit (Viticis Fructus)

“…4. This configuration was supported by some reports on isolation of constituents having the same configuration from congener plants [16][17][18][19]. Since a compound bearing a hemiacetal group generally shows an equilibrium between two stereoisomers, the epimeric ratio varies depending on the solvent and on the temperature [20].…”